Chickenpox
Chickenpox - Summary
Chickenpox is an acute disease, predominantly occurring in childhood. It is caused by varicella-zoster virus and is characterized by a vesicular rash, and often fever and malaise.
Up to 90% of susceptible contacts develop the disease.
Transmission is by personal contact or droplet spread, with an incubation of 1–3 weeks.
Chickenpox is infectious from 1–2 days before the rash appears until the vesicles are dry or have crusted over, usually 5–6 days after the onset of the illness.
The virus persists in sensory nerve ganglia of the dorsal root. Years later, it can reactivate and cause herpes zoster (shingles).
Chickenpox is usually a self-limiting disease in healthy children.
Complications include:
Bacterial skin infection, most common in young children.
Lung involvement, more common in adults.
In pregnancy, severe maternal chickenpox, intrauterine infection, and fetal varicella syndrome. In later pregnancy, varicella can result in premature delivery or neonatal chickenpox infection.
In immunocompromised people, severe disseminated chickenpox with varicella pneumonia, encephalitis, hepatitis, and haemorrhagic complications.
The clinical features of chickenpox include:
Prodromal symptoms such as nausea, myalgia, anorexia, headache, general malaise, and loss of appetite.
Small, erythematous macules which appear on the scalp, face, trunk, and proximal limbs, and progress over 12–14 hours to papules, clear vesicles (which are intensely itchy), and pustules. Vesicles can also occur on the palms and soles, and mucous membranes, with painful and shallow oral or genital ulcers. Vesicles appear in crops. Crusting occurs within 1–4 days, and crusts fall off after 1–2 weeks.
Laboratory tests are rarely required.
For treatment of symptoms, the following can be considered:
Paracetamol or ibuprofen.
Topical calamine lotion.
Chlorphenamine (> 1 year of age).
Aciclovir can be considered for an immunocompetent adult or adolescent (aged 14 years or older) who presents within 24 hours of rash onset, particularly for people with severe chickenpox or those at risk of complications.
Advice should be given about contact with other people and when to seek medical advice.
If serious complications (such as pneumonia, encephalitis, or dehydration) are suspected, admission to hospital should be arranged.
If the person develops a high temperature with redness and pain surrounding the chickenpox lesions (particularly after initial improvement), bacterial superinfection may be present.
Seek urgent specialist advice if a pregnant or breastfeeding woman or a neonate is infected.
Exposure to chickenpox:
Healthy people with a history of chickenpox can be reassured that they are immune. If they are not immune they should be advised that they may develop chickenpox.
If a pregnant woman is exposed to chickenpox, and she has no history, or an uncertain history of chickenpox or shingles, she should be urgently tested for varicella-zoster immunoglobulin G antibodies. If positive, she can be reassured that she is immune. If negative, specialist advice should be sought regarding the need for varicella-zoster immunoglobulin (VZIG) prophylaxis.
Specialist advice is required for neonates or people who are immunocompromised.
Have I got the right topic?
This CKS topic covers the primary care management of chickenpox in healthy children and adults, during pregnancy, in neonates, and in people who are immunocompromised. It also offers advice on the management of healthy children and adults, pregnant women, neonates, and immunocompromised individuals following exposure to a person with chickenpox.
This CKS topic does not cover vaccination against chickenpox.
There are separate CKS topics on Post-herpetic neuralgia and Shingles.
The target audience for this CKS topic is healthcare professionals working within the NHS in the UK, and providing first contact or primary health care.
How up-to-date is this topic?
How up-to-date is this topic?
Changes
February 2013 — minor update. The 2013 QIPP options for local implementation have been added to this topic [NICE, 2013].
November 2012 — reviewed. A literature search was conducted in September 2012 to identify evidence-based guidelines, UK policy, systematic reviews, and key RCTs published since the last revision of the topic. No changes to clinical recommendations have been made.
Previous changes
October 2012 — minor update. The 2012 QIPP options for local implementation have been added to this topic [NPC, 2012].
July 2011 — minor update. More exact paracetamol dosing for children has been introduced by the Medicines and Healthcare products Regulatory Agency [MHRA, 2011]. Prescriptions have been updated to reflect the revised dosing. Issued in July 2011.
May 2011 — minor update. The 2010/2011 QIPP options for local implementation have been added to this topic [NPC, 2011]. Issued in June 2011.
March 2011 — topic structure revised to ensure consistency across CKS topics — no changes to clinical recommendations have been made.
October 2010 — minor update. Generic chlorphenamine is no longer licensed for the treatment of pruritus. Text and prescriptions amended to reflect this. Issued in October 2010.
August 2010 — updated to include advice on considering treatment with aciclovir in adolescents aged 14 years and older if they present within 24 hours of the start of the rash [HPA and Association of Medical Microbiologists, 2010]. Issued in September 2010.
March 2010 — updated to include advice on considering whether bacterial superinfection is complicating chickenpox, particularly in people with eczema. Issued in March 2010.
August 2007 to January 2008 — converted from CKS guidance to CKS topic structure. The evidence-base has been reviewed in detail, and recommendations are more clearly justified and transparently linked to the supporting evidence.
There have been changes to the recommendations regarding symptomatic treatment, antiviral treatment for otherwise healthy adults, and management of chickenpox in a breastfeeding woman.
October 2006 — minor update. Analgesia prescriptions updated because new doses of ibuprofen for children are recommend by the British National Formulary. Issued in October 2006.
October 2005 — minor technical update. Issued in November 2005.
April 2004 — reviewed. Validated in September 2004 and issued in November 2004.
January 2002 — reviewed. Validated in March 2002 and issued in April 2002.
July 1998 — written.
Update
New evidence
Evidence-based guidelines
No new evidence-based guidelines since 1 September 2012.
HTAs (Health Technology Assessments)
No new HTAs since 1 September 2012.
Economic appraisals
No new economic appraisals relevant to England since 1 September 2012.
Systematic reviews and meta-analyses
No new systematic reviews or meta-analyses since 1 September 2012.
Primary evidence
No new randomized controlled trials published in the major journals since 1 September 2012.
New policies
No new national policies or guidelines since 1 September 2012.
New safety alerts
No new safety alerts since 1 September 2012.
Changes in product availability
No changes in product availability since 1 September 2012.
Goals and outcome measures
Goals
To advise on self-care and infection control
To minimize the severity and duration of symptoms
To reduce the likelihood of complications
QIPP - Options for local implementation
QIPP - Options for local implementation
Non-steroidal anti-inflammatory drugs (NSAIDs)
Review the appropriateness of NSAID prescribing widely and on a routine basis, especially in people who are at higher risk of both gastrointestinal (GI) and cardiovascular (CV) morbidity and mortality (e.g. older patients).
If initiating an NSAID is obligatory, use ibuprofen (1200 mg per day or less) or naproxen (1000 mg per day or less).
Review patients currently prescribed NSAIDs. If continued use is necessary, consider changing to ibuprofen (1200 mg per day or less) or naproxen (1000 mg per day or less).
Review and, where appropriate, revise prescribing of etoricoxib to ensure it is in line with MHRA advice and the NICE clinical guideline on osteoarthritis [CSM, 2005; NICE, 2008].
Co-prescribe a proton pump inhibitor (PPI) with NSAIDs for people with osteoarthritis, rheumatoid arthritis, or low back pain (for people over 45 years) in accordance with NICE guidance [NICE, 2008; NICE, 2009a; NICE, 2009b].
Take account of drug interactions when co-prescribing NSAIDs with other medicines (see Summaries of Product Characteristics). For example, co-prescribing NSAIDs with ACE inhibitors or angiotensin receptor blockers (ARBs) may pose particular risks to renal function; this combination should be especially carefully considered and regularly monitored if continued.
Background information
Definition
What is it?
Chickenpox is an acute disease caused by varicella-zoster virus. It is characterized by a vesicular rash, and often fever and malaise [Heininger and Seward, 2006].
Varicella is very infectious; up to 90% of susceptible contacts develop the disease [HPA, 2006].
Transmission is by personal contact or droplet spread, with an incubation period (the time from becoming infected until symptoms appear) of 1–3 weeks [HPA, 2006; DH, 2012].
Chickenpox is infectious from 1–2 days before the rash appears until the vesicles are dry or have crusted over, usually 5–6 days after the onset of the illness (this period may be longer in people who are immunocompromised) [HPA, 2006; DH, 2012].
Once the infection has subsided, the virus persists in sensory nerve ganglia of the dorsal root. Years or decades later, it can reactivate and cause herpes zoster (shingles). For more information see the CKS topics on Post-herpetic neuralgia and Shingles.
It is possible to develop chickenpox after exposure to a person with shingles, but it is not possible to develop shingles from exposure to a person with chickenpox [HPA, 2006].
Prevalence
How common is it?
Chickenpox is predominantly a childhood illness; its incidence is highest before 10 years of age [DH, 2012].
In England and Wales, the incidence of chickenpox is approximately 1290 cases per 100,000 person-years [DTB, 2005a].
Because chickenpox is a common childhood disease, more than 90% of pregnant women are immune (seropositive for varicella-zoster immunoglobulin G). Therefore, although contact with chickenpox in pregnancy is common, primary infection is not (an estimated 3 in 1000 pregnancies are complicated by primary varicella-zoster infection) [RCOG, 2007].
Women from tropical and subtropical areas are more likely to be seronegative for varicella-zoster immunoglobulin G and are therefore more likely to develop chickenpox [RCOG, 2007].
Peak incidence of varicella occurs from March to May, although in recent years there has been less of a seasonal pattern [DH, 2012].
Complications
Certain groups of people may have more serious complications: adults, pregnant women, neonates, and immunocompromised people [HPA, 2006].
In children
Complications in children
Chickenpox is usually a self-limiting disease in healthy children, and complications are rare [Lichenstein, 2006; Papadopoulos, 2007]. However, complications may occur, including [Lichenstein, 2006]:
Skin bacterial superinfection (for example impetigo, furuncles, cellulitis, erysipelas, necrotizing fasciitis) and scarring. This manifests as sudden high grade pyrexia (often after initial improvement), erythema, and tenderness surrounding the original chickenpox lesions.
Neurological complications (for example Reye's syndrome, acute cerebellar ataxia, encephalitis, meningoencephalitis, polyradiculitis, myelitis).
In rare cases, myocarditis, glomerulonephritis, appendicitis, pancreatitis, Henoch–Schönlein purpura, orchitis, arthritis, optic neuritis, iritis, keratitis.
In children younger than 5 years of age, bacterial skin infection is the most common complication [Guess et al, 1986].
In adults
Complications in adults
Chickenpox can be more serious in adults than in children [DH, 2012], and adults with varicella are more likely to be admitted to hospital [Heininger and Seward, 2006].
An adult with chickenpox is 25 times more likely than a child to develop complications [Wilkins et al, 1998]:
Around 5–14% of adults with chickenpox develop lung involvement of varying severity [DTB, 2005a].
Smokers are particularly at greater risk of fulminating varicella pneumonia [DH, 2012].
Of the mortality related to chickenpox in England and Wales, 75% occurs in adults [RCOG, 2007].
Older age is a risk factor for severe varicella disease, and the risk of dying from varicella is highest at extremes of age [Heininger and Seward, 2006].
Shingles can occur from reactivation of latent varicella-zoster infection [Swingler, 2007].
In pregnancy
Complications in pregnancy
Complications for the mother:
Varicella in pregnancy can result in severe chickenpox. The mother is at increased risk of varicella pneumonia and other complications, compared with the general adult population [HPA, 2006; DH, 2012].
Up to 1 in 10 pregnant women with chickenpox develop pneumonia; the severity increases with later gestation [RCOG, 2007].
The case-fatality rate of pregnant women with varicella pneumonia is around 1% in the UK [RCOG, 2007].
Complications for the fetus:
If chickenpox occurs in the first trimester, the risk of spontaneous miscarriage does not seem to be increased [RCOG, 2007].
Infection with varicella-zoster during the first 28 weeks of pregnancy can lead to intrauterine infection and fetal varicella syndrome (previously known as congenital varicella syndrome), which is characterized by one or more of [RCOG, 2007]:
Skin scarring in a dermatomal distribution.
Eye defects (for example microphthalmia, chorioretinitis, cataracts).
Hypoplasia of the limbs.
Neurological abnormalities (microcephaly, cortical atrophy, learning difficulties, dysfunction of bowel and bladder sphincters).
The risk of fetal varicella syndrome is less than 1% in the first 12 weeks, and around 2% between 13 and 20 weeks of pregnancy [HPA, 2006]. Cases of fetal varicella syndrome have been reported in women between 20 and 28 weeks of gestation, indicating that there is a small risk of fetal varicella syndrome when a woman develops chickenpox after 20 weeks of pregnancy [DTB, 2005a; DTB, 2005b; HPA, 2006; RCOG, 2007]. Risk of fetal damage is likely to be substantially lower than the typical fetal varicella syndrome that occurs in the first 20 weeks of pregnancy [HPA, 2006]. There have been no reports of fetal varicella syndrome when the mother has become infected after 28 weeks gestation [RCOG, 2007].
Maternal infection in pregnancy may cause no effect on the fetus or neonate other than presenting as shingles in the first years of the child's life due to reactivation of the primary in-utero infection [RCOG, 2007].
In later pregnancy, varicella can result in premature delivery or neonatal chickenpox infection (more serious if the mother is infected 7 days before birth) [HPA, 2006]. Infection between 1 week before delivery and 1 week after delivery can cause severe neonatal varicella [DH, 2012].
In neonates
Complications in neonates
Neonates are at increased risk of disseminated or haemorrhagic varicella [DH, 2012].
If the mother becomes infected at term, varicella infection of the newborn (perinatal varicella) is a significant risk [RCOG, 2007].
If the mother becomes infected 1–4 weeks before delivery, up to half of babies will be infected; around a quarter of these infants develop clinical varicella, despite passive acquisition of maternal antibody. If the baby is born up to 7 days before or 7 days after onset of the mother's rash, it is more likely to develop varicella of the newborn (perinatal varicella); severe infection is more likely if the maternal onset of rash is 5 days before to 2 days after delivery [RCOG, 2007].
Mother-to-infant transfer of antibodies is limited before 26–28 weeks of gestation. Therefore, infants that are delivered at less than 28 weeks of gestation will not usually be protected against varicella by maternal immunity [DTB, 2005a].
In immunocompromised people
Complications in immunocompromised people
Severe disseminated chickenpox with varicella pneumonia, encephalitis, hepatitis, and haemorrhagic complications is more common in immunocompromised people than other populations [Papadopoulos, 2007; DH, 2012].
Immunocompromised children may develop progressive varicella (involving multiple organs) [Lichenstein, 2006; Breuer and Fifer, 2011].
Other complications which are more common and dangerous in immunocompromised people are secondary complications caused by bacterial superinfection of skin lesions (for example septicaemia, bacterial pneumonia, meningitis) [Papadopoulos, 2007].
Diagnosis
Diagnosis of chickenpox
Diagnosis
How do I know my patient has it?
In most cases, the diagnosis can be made clinically from the characteristic chickenpox rash. If there is doubt, a history of recent exposure to varicella (or herpes zoster), or cases occurring in close contacts, may help confirm the diagnosis.
Features of chickenpox include:
History:
Chickenpox (especially in adults and adolescents) may start with a prodrome that includes nausea, myalgia, anorexia, and headache.
People with chickenpox may also experience general malaise, loss of appetite, and feeding problems.
Examination:
Fever.
Rash:
Small, erythematous macules appear on the scalp, face, trunk, and proximal limbs, which progress over 12–14 hours to papules, clear vesicles (which are intensely itchy), and pustules.
Vesicles can also occur on the palms and soles, and mucous membranes can also be affected, with painful and shallow oral or genital ulcers.
Vesicles appear in crops; stages of development of the rash can therefore differ on different areas of the body.
Crusting occurs within 1–4 days, and crusts fall off after 1–2 weeks.
Adults may experience a more widespread rash and more prolonged fever than children.
Investigations:
Laboratory tests can be used for confirmation but are rarely required. If confirmation is needed in pregnant women, varicella can be detected by virus, antigen, or DNA detection in vesicle fluid.
Basis for recommendation
Basis for recommendation
Clinical features
This recommendation is based on expert opinion in review articles [Heininger and Seward, 2006; Papadopoulos, 2007].
Investigations
This information is based on expert opinion from the Health Protection Agency [HPA, 2011] and expert opinion in a review article [Lichenstein, 2006].
Differential diagnosis
What else might it be?
Chickenpox is usually easy to distinguish from other rashes. However, differential diagnoses include:
Other vesicular viral rashes such as:
Herpes simplex (not usually disseminated).
Herpes zoster (usually unilateral and localized to dermatomes).
Hand, foot, and mouth disease (caused by Coxsackie virus).
Other infections such as:
Impetigo.
Scabies.
Syphilis.
Meningococcaemia (can be confused with haemorrhagic varicella).
Toxic shock syndrome.
Skin disorders such as:
Guttate psoriasis.
Drug eruption.
Insect bites.
Papular urticaria.
Erythema multiforme.
Stevens–Johnson syndrome.
Henoch–Schönlein purpura.
Dermatitis herpetiformis.
Basis for recommendation
Basis for recommendation
This information is based on expert opinion in review articles [Heininger and Seward, 2006; Lichenstein, 2006; Papadopoulos, 2007].
Management
Management
Scenario: Child or adult: covers the management of a child or adult with chickenpox.
Scenario: Pregnant woman: covers the management of a pregnant woman with chickenpox.
Scenario: Breastfeeding woman: covers the management of a breastfeeding woman with chickenpox.
Scenario: Neonate: covers the management of a neonate with chickenpox.
Scenario: Immunocompromised: covers the management of an immunocompromised person with chickenpox.
Scenario: Exposure to chickenpox: covers the management of children, adults (including healthcare workers), pregnant women, breastfeeding women, neonates, and immunocompromised people who have been exposed to chickenpox.
Scenario: Child or adult
Scenario: Management of an otherwise healthy child or adult with chickenpox
Managing otherwise healthy person
How should I manage an otherwise healthy person with chickenpox?
Offer symptomatic treatment.
Consider prescribing aciclovir for an immunocompetent adult or adolescent (aged 14 years or older) with chickenpox who presents within 24 hours of rash onset, particularly for people with severe chickenpox or those at risk of complications, such as smokers or people using corticosteroids.
Aciclovir is not recommended for otherwise healthy children with chickenpox.
Give advice about contact with other people and when to seek medical advice.
If serious complications (such as pneumonia, encephalitis, or dehydration) are suspected, admit to hospital.
If the person develops a high temperature (particularly after initial improvement) with redness and pain surrounding the chickenpox lesions, consider bacterial superinfection and manage accordingly.
This may be more common in people with eczema.
Notify the relevant authorities if in Scotland or Northern Ireland (chickenpox is not a notifiable disease in England or Wales).
For more information on managing a person who has been in contact with but not yet developed chickenpox, see the Scenario: Exposure to chickenpox.
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice, based on recommendations from the Health Protection Agency [HPA, 2006; HPA and Association of Medical Microbiologists, 2012], the UK advisory group on chickenpox on behalf of the British Society for the Study of Infection [Ogilvie, 1998; Wilkins et al, 1998], the British National Formulary [BNF 64, 2012], and a review of the management of varicella-zoster infection [Allen, 2006].
Children
A Cochrane systematic review on aciclovir for treating varicella in otherwise healthy children and adolescents [Klassen and Hartling, 2005] did not find sufficient evidence to support the use of aciclovir in young, immunocompetent children with self-limiting, uncomplicated chickenpox. From the three studies identified, aciclovir was associated with a reduction in the maximum number of lesions and the number of days with fever, but there were no differences in the occurrence of complications of chickenpox in people taking aciclovir compared with placebo. A further literature search for this Cochrane systematic review in September 2008 did not find any new evidence requiring a change to the conclusions.
Adults
Adults are more likely to develop complications of chickenpox than children. There is an indication that smokers and people with severe lung or cardiovascular disease, or those with a chronic skin disorder, are particularly at risk from complicated chickenpox [Wilkins et al, 1998; BNF 64, 2012].
Recommendations are consistent between UK organizations regarding the use of aciclovir in immunocompetent adults with chickenpox [Ogilvie, 1998; Wilkins et al, 1998; BNF 64, 2012; HPA and Association of Medical Microbiologists, 2012].
A review by BMJ Clinical Evidence (search date June 2010) [Breuer and Fifer, 2011] found a systematic review of three randomized controlled trials (RCTs) looking into the use of aciclovir in otherwise healthy adults with chickenpox (n = 316). The included studies found that, compared with placebo in otherwise healthy adults:
Aciclovir given within 24 hours of rash onset reduced the time to full crusting of lesions and reduced the number of lesions.
Aciclovir given more than 24 hours after rash onset showed no significant difference in time to full crusting of lesions or time to no new lesions.
CKS could find no recent trials looking specifically at the effect of aciclovir on preventing complications of chickenpox in an adult population.
Bacterial superinfection
The recommendation to consider the possibility of bacterial superinfection is based on studies that have reviewed people admitted to hospital with chickenpox.
In one UK study (n = 613), 32% of children and 17% of adults admitted to hospital with chickenpox had secondary bacterial skin infection [Bovill and Bannister, 1998]. Of the 25 children with secondary bacterial infection, three had toxin-mediated scarlet fever and one child had scalded skin syndrome. Five of the children with secondary bacterial infection had eczema. Bacteriaemia and toxic shock syndrome, although not seen in this study, may also occasionally occur.
It is plausible that secondary bacterial superinfection is more common in people with eczema. Secondary bacterial infection is itself a common complication of eczema, and use of topical corticosteroids may exacerbate this. Clinical data are sparse, but a small case series supports this view: secondary bacterial infection was more common in children with eczema (31%; 10 of 32 children) than in healthy children (6%; 2 of 34 children) [Kubeyinje, 1995].
Reporting chickenpox
The recommendation on reporting cases of chickenpox in Scotland or Northern Ireland is from the Department of Health [DH, 2012].
Treating symptoms in otherwise healthy person
How should I symptomatically treat an otherwise healthy person with chickenpox?
Offer paracetamol or ibuprofen to relieve pain or fever.
The use of antipyretic agents should be considered in children with fever who appear distressed or unwell. Antipyretic agents should not routinely be used with the sole aim of reducing body temperature in children with fever who are otherwise well. The views and wishes of parents and carers should be taken into consideration.
For further information, see Paracetamol/ibuprofen issues.
Consider the use of topical calamine lotion to alleviate itch.
Chlorphenamine may be useful for itch associated with chickenpox for those who are 1 year of age or older.
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice. Treatment should be directed toward reducing symptoms, such as fever and itchiness [Allen, 2006; Heininger and Seward, 2006; HPA, 2006; NICE, 2007a; Papadopoulos, 2007].
Calamine lotion:
Calamine lotion is thought to relieve pruritus by evaporating from the skin to induce a cooling effect [Allen, 2006].
In a literature review, no published evidence was found to support the use of calamine to alleviate pruritus in chickenpox. However, the authors felt that it has a good safety profile, and anecdotal reports suggest some degree of symptomatic relief [Tebruegge et al, 2006].
CKS could not find any evidence to justify the use of topical crotamiton and colloidal oatmeal bath additives in chickenpox.
Antihistamines:
There is very limited evidence to support the use of topical or systemic antihistamines in relieving pruritus in those with chickenpox. Expert opinion is divided, but some experts find chlorphenamine useful from clinical experience. Piriton®, but not generic chlorphenamine, is licensed for the symptomatic relief of itching due to chickenpox.
Chlorphenamine should not be given to those less than 1 year of age as it is not licensed for use in this age group [ABPI Medicines Compendium, 2010b].
In a literature review, only one randomized trial was found that investigated the effect of antihistamines in chickenpox [Tebruegge et al, 2006]:
Dimetindene (a sedating antihistamine unavailable in UK) was found to be more effective than placebo in reducing itching severity scores, with some improvement in sleep disturbance and appetite [Englisch and Bauer, 1997].
However, the study design was poor, as neither the method of randomization nor the blinding process was described [Tebruegge et al, 2006]. The differences in itching severity scores between the groups were small and of uncertain clinical value. The trial was undertaken by the manufacturer of dimetindene in Germany.
CKS could not identify any other randomized trials on the effect of antihistamines (including chlorphenamine) in people with chickenpox.
Evidence of harm:
CKS found case reports of adverse effects associated with the use of topical diphenhydramine (with or without additional systemic diphenhydramine) in children with chickenpox [Woodward and Baldassano, 1988; Huston et al, 1990; Reilly and Weisse, 1990; Bernhardt, 1991; Chan and Wallander, 1991; McGann et al, 1992].
Reported adverse effects included acute delirium, hallucinations, dilated pupils, urinary retention and facial grimacing. These were thought to be related to the antimuscarinic properties of the drug.
CKS could not find evidence of adverse effects associated with other antihistamines in people with chickenpox.
Advice for someone with chickenpox
What advice should I give to someone with chickenpox?
Advise the following simple measures to help alleviate symptoms:
Encourage adequate fluid intake to avoid dehydration.
Dress appropriately to avoid overheating or shivering.
Wear smooth, cotton fabrics.
Keep nails short to minimize damage from scratching.
Advise that the most infectious period is 1–2 days before the rash appears, but infectivity continues until all the lesions have crusted over (commonly about 5–6 days after the onset of illness):
During this time, advise a person with chickenpox to avoid contact with:
People who are immunocompromised (for example those receiving cancer treatment or high doses of oral steroids, or those with conditions that reduce immunity).
Pregnant women.
Infants aged 4 weeks or less.
Children with chickenpox should be kept away from school or nursery for 5 days from the onset of the rash.
Inform the person to seek urgent medical advice if their condition deteriorates or they develop complications. Parents of young children with chickenpox should be particularly aware of:
Bacterial superinfection — manifesting as sudden high grade pyrexia (often after initial improvement), erythema and tenderness surrounding the original chickenpox lesions.
Dehydration — encourage and monitor fluid intake and seek medical attention if signs of dehydration develop (for example reduced urine output, lethargy, cold peripheries, reduced skin turgor).
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice and are based on an article on the management of chickenpox and shingles infection [Allen, 2006] and feedback from expert reviewers of this CKS topic.
Scenario: Pregnant woman
Scenario: Management of chickenpox in a pregnant woman
Managing a pregnant woman
How should I manage a pregnant woman with chickenpox?
Urgently seek specialist advice regarding the need for diagnostic tests, counselling regarding the risk of fetal varicella syndrome, antiviral treatment, and follow up.
Only prescribe an antiviral drug in primary care (with the informed consent of the woman) on the advice of a specialist.
Offer symptomatic treatment.
Give advice about contact with other people and when to seek medical advice.
Monitor the woman closely (review daily, or earlier if her condition deteriorates).
Refer for urgent hospital assessment if fever persists, or cropping of the rash continues after 6 days.
Admit to hospital (preferably somewhere with access to specialists in obstetrics, infectious diseases, and paediatrics) if the woman has chest symptoms, neurological symptoms other than headache, haemorrhagic rash or bleeding, severe disease (for example dense rash with or without numerous mucosal lesions), or significant immunosuppression.
Seek specialist advice from the local obstetric unit (even in the absence of complications) if monitoring will be difficult; the woman is in the latter half of pregnancy; or the woman has a complicated obstetric history, history of smoking, chronic lung disease, or poor social circumstances, or is taking steroids.
Notify the relevant authorities if in Scotland or Northern Ireland (chickenpox is not a notifiable disease in England or Wales).
For more information on managing a pregnant woman who has been in contact with but not yet developed chickenpox, see Scenario: Exposure to chickenpox.
Basis for recommendation
Basis for recommendation
The recommendations for primary healthcare professionals on what to advise the woman, symptomatic treatment, and when to refer for specialist care are based on a guideline from the Royal College of Obstetricians and Gynaecologists (RCOG) on chickenpox in pregnancy [RCOG, 2007], guidance from the Health Protection Agency (HPA) on the management of rash illness and exposure to rash illness in pregnancy [HPA, 2011], and an article in the Drug and Therapeutics Bulletin [DTB, 2005a].
Reporting chickenpox
The recommendation on reporting cases of chickenpox is from the Department of Health [DH, 2012].
Urgent specialist advice
Pregnant women are more at risk of serious complications of varicella (for example fulminating varicella pneumonia). This risk is greatest in the second, and early in the third, trimester [DH, 2012].
There are prescribing and drug licensing issues in pregnancy, and a potential need for intervention and follow up. The RCOG guideline on chickenpox in pregnancy [RCOG, 2007] advises that a pregnant woman needs to be informed of the small risk of fetal varicella syndrome and its implications if she develops varicella or shows serological conversion in the first 28 weeks of pregnancy. The guideline recommends considering referral to a specialist centre for detailed ultrasonography at 16–20 weeks of gestation or 5 weeks after infection (if specialist advice has been sought, this is likely to be arranged by secondary care).
Antiviral treatment
Only limited data on the treatment of chickenpox in pregnancy are available [DTB, 2005a], therefore CKS recommends seeking specialist advice.
Guidance on the management of rash illness in pregnancy from the HPA [HPA, 2011] and RCOG guidelines on chickenpox in pregnancy [RCOG, 2007] recommend offering a 7-day course of oral aciclovir (with informed consent) if the woman presents within 24 hours of the onset of the chickenpox rash and is 20 weeks pregnant or more. This is based on a consensus decision from the UK Advisory Group on Chickenpox that, considering the available evidence and the increased risk of pneumonitis in the latter half of pregnancy, the risk balance is in favour of giving oral aciclovir to women in the second half of pregnancy presenting within 24 hours of rash onset [Nathwani et al, 1998].
If the woman is less than 20 weeks pregnant the HPA and RCOG state that aciclovir should be used with caution [RCOG, 2007; HPA, 2011].
The RCOG guideline found data to suggest no increase in the risk of fetal malformation with aciclovir in pregnancy, although there is a theoretical risk of teratogenesis in the first trimester [RCOG, 2007].
Varicella-zoster immunoglobulin has no benefit once chickenpox has developed [RCOG, 2007].
Treating symptoms in pregnancy
How should I symptomatically treat a pregnant woman with chickenpox?
Offer paracetamol to relieve pain or fever.
Ibuprofen may be considered but it should not be used beyond 27 weeks of gestation. For further information, see Choice in pregnancy or breastfeeding.
Consider the use of topical calamine lotion to alleviate itch.
The use of chlorphenamine is not recommended for the symptomatic management of chickenpox in pregnancy.
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice. Treatment should be directed toward reducing symptoms, such as fever and itchiness [Allen, 2006; Heininger and Seward, 2006; HPA, 2006; Papadopoulos, 2007].
Calamine lotion
Calamine lotion is thought to relieve pruritus by evaporating from the skin to induce a cooling effect [Allen, 2006].
In a literature review, no published evidence was found to support the use of calamine to alleviate pruritus in chickenpox. However, the authors felt that it has a good safety profile, and anecdotal reports suggest some degree of symptomatic relief [Tebruegge et al, 2006].
The safety of calamine lotion during pregnancy and lactation has not been established, but its use during these periods is not considered to constitute a hazard [ABPI Medicines Compendium, 2011a].
Topical crotamiton and colloidal oatmeal bath additives
CKS found no evidence to justify the use of topical crotamiton and colloidal oatmeal bath additives in chickenpox.
Antihistamines
Although chlorphenamine may be used during pregnancy for the treatment of allergic conditions [Schaefer et al, 2007], CKS found no evidence to support its use in pregnant women with chickenpox.
Although no increased teratogenic risk has been reported in pregnancies exposed to chlorphenamine [Schaefer et al, 2007] and there are extensive data on the use of chlorphenamine in pregnancy which do not indicate an increased risk of fetal toxicity if exposure occurs [NTIS, 2009], it is generally advised that drugs should be avoided if possible during the first trimester [BNF 64, 2012].
The manufacturer of chlorphenamine advises using the drug when the potential benefits outweigh the potential unknown risks to the fetus [ABPI Medicines Compendium, 2011c]. Evidence to support the use of antihistamines for symptomatic relief in chickenpox is extremely limited. On this basis, even though the risks of chlorphenamine use in pregnancy appear to be low, CKS does not recommend its use for the symptomatic relief of chickenpox in pregnancy.
Advice for someone with chickenpox
What advice should I give to someone with chickenpox?
Advise the following simple measures to help alleviate symptoms:
Encourage adequate fluid intake to avoid dehydration.
Dress appropriately to avoid overheating or shivering.
Wear smooth, cotton fabrics.
Keep nails short to minimize damage from scratching.
Advise that the most infectious period is 1–2 days before the rash appears, but infectivity continues until all the lesions have crusted over (commonly about 5–6 days after the onset of illness):
During this time, advise a person with chickenpox to avoid contact with:
People who are immunocompromised (for example those receiving cancer treatment or high doses of oral steroids, or those with conditions that reduce immunity).
Pregnant women.
Infants aged 4 weeks or less.
Children with chickenpox should be kept away from school or nursery for 5 days from the onset of the rash.
Inform the person to seek urgent medical advice if their condition deteriorates or they develop complications. Parents of young children with chickenpox should be particularly aware of:
Bacterial superinfection — manifesting as sudden high grade pyrexia (often after initial improvement), erythema and tenderness surrounding the original chickenpox lesions.
Dehydration — encourage and monitor fluid intake and seek medical attention if signs of dehydration develop (for example reduced urine output, lethargy, cold peripheries, reduced skin turgor).
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice and are based on an article on the management of chickenpox and shingles infection [Allen, 2006] and feedback from expert reviewers of this CKS topic.
Scenario: Breastfeeding woman
Scenario: Management of chickenpox in a woman who is breastfeeding
Managing a breastfeeding woman
How should I manage a woman with chickenpox who is breastfeeding?
Offer symptomatic treatment.
Consider prescribing aciclovir for an immunocompetent woman who presents within 24 hours of rash onset, particularly if she has severe chickenpox or is at risk of complications.
Seek urgent specialist advice regarding whether the mother should continue to breastfeed if she has chickenpox, and whether her baby requires treatment to minimize the risk of complications.
Give advice about contact with other people and when to seek medical advice.
Admit to hospital if serious complications (for example pneumonia, encephalitis) are suspected.
Notify the relevant authorities if in Scotland or Northern Ireland (chickenpox is not a notifiable disease in England or Wales).
Basis for recommendation
Basis for recommendation
CKS found no specific guidelines on the management of breastfeeding women with chickenpox. Therefore, CKS suggest symptomatic management as for healthy adults, in line with current knowledge about the use of analgesics/antipyretics and calamine in breastfeeding women.
Adults are more likely to develop complications of chickenpox than children. There is an indication that smokers and people with severe lung or cardiovascular disease, or those with a chronic skin disorder, are particularly at risk from complicated chickenpox [Wilkins et al, 1998; BNF 64, 2012].
Recommendations are consistent between UK organizations regarding the use of aciclovir in immunocompetent adults with chickenpox [Ogilvie, 1998; Wilkins et al, 1998; BNF 64, 2012; HPA and Association of Medical Microbiologists, 2012].
A review by BMJ Clinical Evidence (search date June 2010) [Breuer and Fifer, 2011] found a systematic review of three RCTs looking into the use of aciclovir in otherwise healthy adults with chickenpox (n = 316). The included studies found that, compared with placebo in otherwise healthy adults:
Aciclovir given within 24 hours of rash onset reduced the time to full crusting of lesions and reduced the number of lesions.
Aciclovir given more than 24 hours after rash onset showed no significant difference in time to full crusting of lesions or time to no new lesions.
CKS could find no recent trials looking specifically at the effect of aciclovir on preventing complications of chickenpox in an adult population.
There is a theoretical risk of aciclovir affecting an infant's immune system as a result of exposure via breast milk. However, toxic symptoms have not been reported and breastfeeding can continue if a woman is taking aciclovir [Schaefer et al, 2007].
CKS advises seeking specialist advice regarding whether a mother with chickenpox should breastfeed in view of the potential complications for the baby.
Recommendations on breastfeeding from the Health Protection Agency guidance on the management of rash illness and exposure to rash illness in pregnancy state that: if the mother has chickenpox, she should be allowed to breastfeed. If lesions are close to the nipple, milk should be expressed from the affected side until lesions have crusted. This milk can be fed to the baby if he or she is covered by varicella-zoster immunoglobulin and/or aciclovir. These treatments should be initiated by a specialist [HPA, 2011].
The recommendation on reporting cases of chickenpox is from the Department of Health [DH, 2012].
Treating symptoms in breastfeeding
How should I symptomatically treat a woman with chickenpox who is breastfeeding?
Offer paracetamol or ibuprofen to relieve pain or fever. For further information, see Choice in pregnancy or breastfeeding.
Consider the use of topical calamine lotion to alleviate itch.
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice. Treatment should be directed toward reducing symptoms, such as fever and itchiness [Allen, 2006; Heininger and Seward, 2006; HPA, 2006; Papadopoulos, 2007].
Calamine lotion:
Calamine lotion is thought to relieve pruritus by evaporating from the skin to induce a cooling effect [Allen, 2006].
In a literature review, no published evidence was found to support the use of calamine to alleviate pruritus in chickenpox. However, the authors felt that it has a good safety profile, and anecdotal reports suggest some degree of symptomatic relief [Tebruegge et al, 2006].
The safety of calamine lotion during pregnancy and lactation has not been established, but its use during these periods is not considered to constitute a hazard [ABPI Medicines Compendium, 2011a].
CKS could not find any evidence to justify the use of topical crotamiton and colloidal oatmeal bath additives in chickenpox.
Antihistamines:
Although the sedating antihistamine chlorphenamine is licensed for relief of itching associated with chickenpox, there is very limited evidence to support the use of topical or systemic antihistamines in relieving pruritus in those with chickenpox.
Chlorphenamine may inhibit lactation and may be secreted in breast milk [ABPI Medicines Compendium, 2010a; ABPI Medicines Compendium, 2010b].
Given that there is no detailed knowledge about the effect of chlorphenamine on breastfeeding [Schaefer et al, 2007], CKS does not recommend its use in breastfeeding women.
Advice for someone with chickenpox
What advice should I give to someone with chickenpox?
Advise the following simple measures to help alleviate symptoms:
Encourage adequate fluid intake to avoid dehydration.
Dress appropriately to avoid overheating or shivering.
Wear smooth, cotton fabrics.
Keep nails short to minimize damage from scratching.
Advise that the most infectious period is 1–2 days before the rash appears, but infectivity continues until all the lesions have crusted over (commonly about 5–6 days after the onset of illness):
During this time, advise a person with chickenpox to avoid contact with:
People who are immunocompromised (for example those receiving cancer treatment or high doses of oral steroids, or those with conditions that reduce immunity).
Pregnant women.
Infants aged 4 weeks or less.
Children with chickenpox should be kept away from school or nursery for 5 days from the onset of the rash.
Inform the person to seek urgent medical advice if their condition deteriorates or they develop complications. Parents of young children with chickenpox should be particularly aware of:
Bacterial superinfection — manifesting as sudden high grade pyrexia (often after initial improvement), erythema and tenderness surrounding the original chickenpox lesions.
Dehydration — encourage and monitor fluid intake and seek medical attention if signs of dehydration develop (for example reduced urine output, lethargy, cold peripheries, reduced skin turgor).
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice and are based on an article on the management of chickenpox and shingles infection [Allen, 2006] and feedback from expert reviewers of this CKS topic.
Scenario: Neonate
Scenario: Management of chickenpox in a neonate
Managing a neonate
How should I manage a neonate with chickenpox?
Seek urgent specialist advice regarding further management.
Give advice about contact with other people.
Admit to hospital if serious complications (for example pneumonia, encephalitis) are suspected.
Notify the relevant authorities if in Scotland or Northern Ireland (chickenpox is not a notifiable disease in England or Wales).
For more information on managing neonates who have been in contact with, but not yet developed chickenpox, see Scenario: Exposure to chickenpox.
Basis for recommendation
Basis for recommendation
CKS recommends seeking specialist advice on the management of neonates with chickenpox because of the increased risk of severe disease and complications in this group.
The recommendation on reporting cases of chickenpox is from the Health Protection Agency [DH, 2012].
Neonates with chickenpox should be treated with aciclovir [RCOG, 2007; HPA, 2011], but this should only be initiated by a specialist.
The Royal College of Obstetricians and Gynaecologists' guidelines on chickenpox in pregnancy state that varicella-zoster immunoglobulin is not beneficial if neonatal chickenpox has already developed [RCOG, 2007].
The Health Protection Agency advises that if severe varicella develops in a neonate who has been given varicella-zoster immunoglobulin following exposure to chickenpox, treatment with high-dose intravenous aciclovir should be started as soon as possible [HPA, 2011].
Advice for someone with chickenpox
What advice should I give to someone with chickenpox?
Advise the following simple measures to help alleviate symptoms:
Encourage adequate fluid intake to avoid dehydration.
Dress appropriately to avoid overheating or shivering.
Wear smooth, cotton fabrics.
Keep nails short to minimize damage from scratching.
Advise that the most infectious period is 1–2 days before the rash appears, but infectivity continues until all the lesions have crusted over (commonly about 5–6 days after the onset of illness):
During this time, advise a person with chickenpox to avoid contact with:
People who are immunocompromised (for example those receiving cancer treatment or high doses of oral steroids, or those with conditions that reduce immunity).
Pregnant women.
Infants aged 4 weeks or less.
Children with chickenpox should be kept away from school or nursery for 5 days from the onset of the rash.
Inform the person to seek urgent medical advice if their condition deteriorates or they develop complications. Parents of young children with chickenpox should be particularly aware of:
Bacterial superinfection — manifesting as sudden high grade pyrexia (often after initial improvement), erythema and tenderness surrounding the original chickenpox lesions.
Dehydration — encourage and monitor fluid intake and seek medical attention if signs of dehydration develop (e.g. reduced urine output, lethargy, cold peripheries, reduced skin turgor).
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice and are based on an article on the management of chickenpox and shingles infection [Allen, 2006] and feedback from expert reviewers of this CKS topic.
Scenario: Immunocompromised
Scenario: Management of chickenpox in an immunocompromised person
Managing an immunocompromised person
How should I manage an immunocompromised person with chickenpox?
Seek immediate specialist advice regarding confirming the diagnosis of chickenpox and whether urgent antiviral treatment is required.
Offer symptomatic treatment.
Give advice about contact with other people and when to seek medical advice.
Admit to hospital if serious complications (for example pneumonia, or encephalitis) are suspected.
Notify the relevant authorities if in Scotland or Northern Ireland (chickenpox is not a notifiable disease in England or Wales).
For advice on how to manage an immunocompromised person who has been exposed to but not yet developed chickenpox, see Scenario: Exposure to chickenpox.
Basis for recommendation
Basis for recommendation
CKS recommends seeking specialist advice on the management of immunocompromised people with chickenpox because of the increased risk of severe disease and complications in this group.
The recommendation on reporting cases of chickenpox is from the Department of Health [DH, 2012].
People at higher risk of serious complications from chickenpox may be given antiviral drugs, such as aciclovir, to try to prevent severe illness [HPA, 2006; DH, 2012].
Even immunocompromised people who have received varicella-zoster immunoglobulin prophylaxis may develop severe or fatal varicella. These people should be carefully monitored and given aciclovir at the first sign of illness [DH, 2012].
Treating symptoms in immunocompromised
How should I symptomatically treat an immunocompromised person with chickenpox?
Offer paracetamol or ibuprofen to relieve pain or fever:
The use of antipyretic agents should be considered in children with fever who appear distressed or unwell. Antipyretic agents should not routinely be used with the sole aim of reducing body temperature in children with fever who are otherwise well. The views and wishes of parents and carers should be taken into consideration.
For further information, see Paracetamol/ibuprofen issues.
Consider the use of topical calamine lotion to alleviate itch.
Chlorphenamine may be useful for itch associated with chickenpox for children aged 1 year and above.
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice. Treatment should be directed toward reducing symptoms, such as fever and itchiness [Allen, 2006; Heininger and Seward, 2006; HPA, 2006; NICE, 2007a; Papadopoulos, 2007].
Calamine lotion:
Calamine lotion is thought to relieve pruritus by evaporating from the skin to induce a cooling effect [Allen, 2006].
In a literature review, no published evidence was found to support the use of calamine to alleviate pruritus in chickenpox. However, the authors felt that it has a good safety profile, and anecdotal reports suggest some degree of symptomatic relief [Tebruegge et al, 2006].
CKS could not find any evidence to justify the use of topical crotamiton and colloidal oatmeal bath additives in chickenpox.
Antihistamines:
There is very limited evidence to support the use of topical or systemic antihistamines in relieving pruritus in those with chickenpox. Expert opinion is divided, but some experts find chlorphenamine useful from clinical experience. Piriton®, but not generic chlorphenamine, is licensed for the symptomatic relief of itching due to chickenpox.
Chlorphenamine should not be given to those less than 1 year of age as it is not licensed for use in this age group [ABPI Medicines Compendium, 2010b].
In a literature review, only one randomized trial was found that investigated the effect of antihistamines in chickenpox [Tebruegge et al, 2006]:
Dimetindene (a sedating antihistamine unavailable in UK) was found to be more effective than placebo in reducing itching severity scores, with some improvement in sleep disturbance and appetite [Englisch and Bauer, 1997].
However, the study design was poor, as neither the method of randomization nor the blinding process was described [Tebruegge et al, 2006]. The differences in itching severity scores between the groups were small and of uncertain clinical value. The trial was undertaken by the manufacturer of dimetindene in Germany.
CKS found no other randomized trials on the effect of antihistamines (including chlorphenamine) in people with chickenpox.
Evidence of harm:
CKS found case reports of adverse effects associated with the use of topical diphenhydramine (with or without additional systemic diphenhydramine) in children with chickenpox [Woodward and Baldassano, 1988; Huston et al, 1990; Reilly and Weisse, 1990; Bernhardt, 1991; Chan and Wallander, 1991; McGann et al, 1992].
Reported adverse effects included acute delirium, hallucinations, dilated pupils, urinary retention and facial grimacing. These were thought to be related to the antimuscarinic properties of the drug.
CKS found no evidence of adverse effects associated with other antihistamines in people with chickenpox.
Advice for someone with chickenpox
What advice should I give to someone with chickenpox?
Advise the following simple measures to help alleviate symptoms:
Encourage adequate fluid intake to avoid dehydration.
Dress appropriately to avoid overheating or shivering.
Wear smooth, cotton fabrics.
Keep nails short to minimize damage from scratching.
Advise that the most infectious period is 1–2 days before the rash appears, but infectivity continues until all the lesions have crusted over (commonly about 5–6 days after the onset of illness):
During this time, advise a person with chickenpox to avoid contact with:
People who are immunocompromised (for example those receiving cancer treatment or high doses of oral steroids, or those with conditions that reduce immunity).
Pregnant women.
Infants aged 4 weeks or less.
Children with chickenpox should be kept away from school or nursery for 5 days from the onset of the rash.
Inform the person to seek urgent medical advice if their condition deteriorates or they develop complications. Parents of young children with chickenpox should be particularly aware of:
Bacterial superinfection — manifesting as sudden high grade pyrexia (often after initial improvement), erythema and tenderness surrounding the original chickenpox lesions.
Dehydration — encourage and monitor fluid intake and seek medical attention if signs of dehydration develop (for example reduced urine output, lethargy, cold peripheries, reduced skin turgor).
Basis for recommendation
Basis for recommendation
These recommendations are pragmatic advice and are based on those issued by the Health Protection Agency [HPA, 2006], an article on the management of chickenpox and shingles infection [Allen, 2006], and feedback from expert reviewers of this CKS topic.
Scenario: Exposure to chickenpox
Scenario: Management of a person who has been exposed to chickenpox
Assessment of chickenpox contacts
How should I assess chickenpox contacts?
For all people with a history of exposure to chickenpox, establish whether:
The diagnosis of chickenpox in the contact is certain.
The exposure was significant enough to put the person at risk of infection.
The person has had chickenpox in the past.
The person is at increased risk of complications of chickenpox (for example pregnant women, immunocompromised people, neonates).
For management of a person who has been exposed to shingles, see the CKS topics on Post-herpetic neuralgia and Shingles.
Basis for recommendation
Basis for recommendation
This recommendation is based on Department of Health guidance on immunisation against infectious disease: The 'Green Book' [DH, 2012].
Post-exposure management aims to protect people at high risk of developing varicella and people who may transmit infection to those at high risk (for example healthcare workers) [DH, 2012].
Significant exposure to chickenpox
What is significant exposure to chickenpox?
Significant exposure takes into account:
The type of varicella-zoster infection in the index case. The risk of acquiring infection from an immunocompetent person who does not have exposed zoster lesions is unlikely. Exposure is significant if the person has had contact with:
Chickenpox.
Disseminated zoster.
Immunocompetent people with exposed lesions (for example ophthalmic zoster).
Immunosuppressed people with localized zoster on any part of the body (because this group may have increased viral shedding).
The timing of exposure in relation to the rash onset in the index case. Exposure is significant if the person was in contact with:
Chickenpox — between 48 hours before onset of rash to crusting of lesions.
Disseminated zoster — from 48 hours before onset of rash to crusting of lesions.
Localized zoster — day of onset of rash until crusting of lesions.
Closeness of contact. Exposure is significant if it is through:
Maternal/neonatal contact.
Continuous home contact.
Contact in the same room (for example house or classroom, or 2- to 4-bed hospital bay) for 15 minutes or more, or contact on large open wards (particularly paediatric wards).
Face-to-face contact (for example having a conversation).
Basis for recommendation
Basis for recommendation
This information is based on Department of Health guidance on immunisation against infectious disease: The 'Green Book' [DH, 2012].
Healthy person
How should I manage a healthy person who has been in contact with chickenpox?
Perform a general assessment to establish the person's risk of chickenpox on the basis of their history of chickenpox, the certainty of chickenpox in the contact, and the level of exposure.
If the person's exposure to chickenpox is not significant, or if they have a history of chickenpox, or if they are known to be immune to chickenpox, reassure.
People with a definite history of chickenpox or herpes zoster can be considered to be protected.
If the person is not immune, advise them that they may develop chickenpox.
Healthcare workers with significant exposure to the varicella-zoster virus who have been vaccinated or have a definite history of chickenpox or zoster can continue working (as they are considered protected), but should be advised to contact their occupational health department before patient contact if they feel unwell or develop a rash.
Unvaccinated healthcare workers with a negative or uncertain history of chickenpox or herpes zoster should be serologically tested.
Consider routine testing for healthcare workers born and raised overseas, for whom a history of chickenpox is a less reliable indicator of immunity.
If there is no definite history of varicella-zoster virus infection but a varicella-zoster virus antibody test is positive, consider the person to be immune.
Non-immune healthcare workers should be advised to avoid contact with high-risk patients for 8–21 days after their contact with chickenpox, and to report to their occupational health department before patient contact if they feel unwell or develop a fever or rash.
If a healthcare worker has no varicella-zoster antibody, varicella vaccine should be offered to reduce the risk of exposing patients to varicella-zoster virus in the future.
Healthcare workers
Healthcare workers
The definition of a healthcare worker includes people who work in hospitals and general practice who have contact with patients. Examples include:
Medical and nursing staff.
Ward cleaners.
Catering staff.
Ambulance staff.
Receptionists in general practice.
[DH, 2012]
Basis for recommendation
Basis for recommendation
This recommendation is pragmatic advice, taking into account guidance from the Department of Health on immunisation against infectious disease [DH, 2012] and guidelines on chickenpox in pregnancy from the Royal College of Obstetricians and Gynaecologists [RCOG, 2007].
Pregnant woman
How should I manage a pregnant woman who has been in contact with chickenpox?
Perform a general assessment to establish the woman's risk of chickenpox, on the basis of her history of chickenpox, the certainty of chickenpox in the contact, and the level of exposure.
If the woman has a definite history of chickenpox or shingles, reassure her that she is not at risk of chickenpox because immunity can be assumed.
If the woman has no history of chickenpox or shingles (or is uncertain) and has a history of significant contact:
Establish the stage of gestation (weeks from the last menstrual period).
Test for varicella-zoster immunoglobulin G (IgG) antibodies in primary care if test results can be available within 2 working days of first exposure. If this is not possible, urgently seek specialist advice because testing in secondary care and/or varicella-zoster immunoglobulin (VZIG) prophylaxis may be needed.
If the test shows varicella-zoster immunoglobulin G, reassure the woman that she is immune and cannot catch chickenpox.
If the woman's antibody status is negative, urgently seek specialist advice regarding the need for VZIG.
Advise the woman to promptly seek advice from her doctor or midwife if she develops a rash and has had contact with chickenpox, regardless of whether she has received VZIG.
Basis for recommendation
Basis for recommendation
This recommendation is based on Department of Health guidance on the management of exposure to varicella [DH, 2012], guidance from the Health Protection Agency on the management of rash illness in pregnancy [HPA, 2011], and guidance from the Royal College of Obstetricians and Gynaecologists on chickenpox in pregnancy [RCOG, 2007]:
CKS suggests testing for varicella-zoster immunoglobulin G antibodies in primary care if the results can be available within 2 working days of first exposure (to allow time for referral to secondary care if necessary), taking into account the Royal College of Obstetricians and Gynaecologists guideline on chickenpox in pregnancy [RCOG, 2007], which states that if the woman's immune status is unknown, the administration of VZIG can be delayed until serology results are available, if the laboratory turnaround time is 24–48 hours. However, local arrangements may differ, and it is advisable to contact the local laboratory to determine whether a result will be available within this time.
CKS recommends seeking specialist advice regarding the management of non-immune pregnant women who have been in contact with chickenpox, in view of the potential for the development of severe disease and serious complications for the woman and fetus and the possible need for varicella-zoster immunoglobulin.
CKS found no published controlled trials of the use of prophylactic oral aciclovir in pregnancy. Aciclovir, valaciclovir, and famciclovir are not licensed in the UK for this indication and are generally not recommended [DTB, 2005a].
The local microbiologist or virologist will usually decide whether to give varicella-zoster immunoglobulin [DTB, 2005a].
The Department of Health recommends that a pregnant woman who has a negative antibody status should receive varicella-zoster immunoglobulin within 10 days of exposure [DH, 2012].
Neonate
How should I manage a neonate who has been in contact with chickenpox?
Perform a general assessment to establish the neonate's risk of chickenpox, on the basis of the certainty of chickenpox in the contact and the level of exposure.
If the neonate's mother is the contact, determine when, in relation to delivery, she developed chickenpox. If someone else is the contact, determine the age of the neonate at the time of contact.
Seek urgent specialist advice regarding the need for testing and further management, and whether the mother should continue to breastfeed if she has chickenpox.
All neonates with exposure from their mother, or elsewhere, must be followed up for 14–16 days by a GP, midwife, or health visitor, or in hospital. Monitor the infant for signs of infection for 14–16 days.
Basis for recommendation
Basis for recommendation
Recommendations regarding monitoring of an neonate who has been exposed to chickenpox are based on the Royal College of Obstetricians and Gynaecologists' guideline on chickenpox in pregnancy [RCOG, 2007], and a Drug and Therapeutics Bulletin [DTB, 2005a].
CKS recommends seeking specialist advice in the management of a neonate who has been exposed to chickenpox or shingles because severe disease or complications can develop in this group. Depending on the time of exposure, there are a number of management strategies which may be undertaken in secondary care.
Varicella-zoster immunoglobulin (VZIG) may not prevent chickenpox but is generally effective in reducing the severity of infection [Isaacs, 2000].
The Department of Health's Green Book advises giving VZIG or intravenous aciclovir to the neonate depending on when the mother develops varicella in relation to delivery [DH, 2012]. This should only be done in a specialist setting.
CKS advises seeking specialist advice regarding whether a mother with chickenpox should breastfeed in view of the potential complications for the baby.
Recommendations on breastfeeding from the Health Protection Agency guidance on the management of rash illness and exposure to rash illness in pregnancy state that: if the mother has chickenpox, she should be allowed to breastfeed. If lesions are close to the nipple, milk should be expressed from the affected side until lesions have crusted. This milk can be fed to the baby if he or she is covered by varicella-zoster immunoglobulin and/or aciclovir. These treatments should be initiated by a specialist [HPA, 2011].
Immunocompromised person
How should I manage an immunocompromised person who has been in contact with chickenpox?
Perform a general assessment to establish the certainty of chickenpox in the contact, the level of exposure, and whether the person fulfils the criteria for immunosuppression. If in doubt, seek specialist advice.
Urgently seek specialist advice regarding further management.
People who have had a significant exposure to chickenpox and who are immunocompromised should be tested for varicella-zoster antibody, regardless of their history of chickenpox. Test for varicella-zoster immunoglobulin G (IgG) antibodies in primary care if test results can be available within 2 working days of first exposure. If this is not possible, urgently seek specialist advice because testing in secondary care and/or varicella-zoster immunoglobulin prophylaxis may be needed.
Basis for recommendation
Basis for recommendation
This recommendation is based on Department of Health guidance on immunisation against infectious disease: The 'Green Book' [DH, 2012].
CKS recommends urgently seeking specialist advice on the management of an immunocompromised person who has been in contact with chickenpox, in view of the potential for severe disease and complications in this group.
The Department of Health recommends referral of anyone who fulfils the following criteria for consideration of varicella-zoster immunoglobulin prophylaxis [DH, 2012]:
Significant exposure to chickenpox or herpes zoster, and
A clinical condition that increases the risk of severe varicella (e.g. immunocompromised people, neonates, and pregnant women), and
No antibodies to varicella-zoster virus.
CKS suggests testing for varicella-zoster immunoglobulin G antibodies in primary care if the results can be available within 2 working days of first exposure (to allow time for referral to secondary care if necessary), taking into account the practicalities of testing in a primary care setting and feedback from expert reviewers. However, local arrangements may differ, and it is advisable to contact the local laboratory to determine whether a result will be available within this time.
The Department of Health recommends that an immunocompromised person who has a negative antibody status (or for whom results cannot be available within 7 days of exposure) should receive varicella-zoster immunoglobulin, ideally within 7 days of exposure [DH, 2012]. This should be done in a specialist setting.
Important aspects of prescribing information relevant to primary healthcare are covered in this section specifically for the drugs recommended in this CKS topic. For further information on contraindications, cautions, drug interactions, and adverse effects, see the electronic Medicines Compendium (eMC) (http://medicines.org.uk/emc), or the British National Formulary (BNF) (www.bnf.org).
Analgesics / Antipyretics
Paracetamol/ibuprofen issues
What are the general issues when prescribing paracetamol or ibuprofen?
Paracetamol and ibuprofen are licensed for the relief of pain and fever from 3 months of age [BNF 64, 2012]:
Both drugs are recommended for the management of feverish illnesses in children younger than 5 years of age [NICE, 2007a].
For use in pregnancy or breastfeeding, see Choice in pregnancy or breastfeeding.
As with other nonsteroidal anti-inflammatory drugs (NSAIDs), ibuprofen may worsen or precipitate gastrointestinal haemorrhage, asthma, hypertension, renal impairment, or cardiac failure. Avoid ibuprofen if there is a history of peptic ulcers. Paracetamol is often a safer option in older people.
Ibuprofen may occasionally cause exacerbation of asthma and gastrointestinal adverse effects, such as discomfort, nausea, and diarrhoea [BNF 64, 2012].
There are concerns that use of NSAIDs in children with varicella is associated with an increased risk of necrotizing soft-tissue infections and infections with invasive group A beta-haemolytic streptococci [Heininger and Seward, 2006]:
Evidence from two small case-control studies are conflicting [Lesko and Mitchell, 1995; Zerr et al, 1999].
Although the association cannot be ruled out with certainty, evidence is insufficient to advise that ibuprofen (or other NSAIDs) be avoided in children with chickenpox.
Paracetamol has no notable adverse effects when used at the correct dosage [BNF 64, 2012].
Choice in pregnancy or breastfeeding
Which analgesic and antipyretic treatment is suitable for use during pregnancy or when breastfeeding?
Paracetamol is the analgesic and antipyretic of choice because it can be used at the usual dosage and at any stage of pregnancy and during breastfeeding.
Ibuprofen may be considered for use in breastfeeding and pregnant women, but it should not used beyond 27 weeks of gestation because of the increased risk of constriction of the ductus arteriosus.
Constriction of ductus arteriosus:
Constriction is related to gestational age; it is rare before week 27, but its incidence increases with advancing gestational age to 50–70% at 32 weeks and up to 100% with exposure from week 34 onwards.
The effect appears not to be dose dependent.
If use of ibuprofen is unavoidable, fetal circulation should be monitored regularly (once or twice weekly) with Doppler sonography, and medication use should be stopped as soon as signs of ductal constriction appear.
Breastfeeding:
Ibuprofen was not detected in breast milk following administration of 800–1600 mg daily in two small studies. No adverse effects on breastfed children were reported in both studies and also in a prospective study covering 21 mother-child pairs.
Antiviral drugs
Adult
Which antiviral should I prescribe for an adult with chickenpox?
Aciclovir is the preferred antiviral drug for the treatment of chickenpox in adults.
Aciclovir is licensed for the treatment of chickenpox.
If aciclovir is indicated, a dose of 800 mg five times daily for seven days should be prescribed.
Treatment should begin within 24 hours of the onset of the rash.
Other antivirals are not recommended as they are not licensed for the treatment of chickenpox.
Basis for recommendation
This information is based on the manufacturer's Summary of Product Characteristics for Zovirax® [ABPI Medicines Compendium, 2011b] and the British National Formulary [BNF 64, 2012].
Pregnancy
Which antiviral drug should I prescribe for a pregnant woman with chickenpox?
Aciclovir is the preferred antiviral drug because of its long-term safety data in pregnant women.
A dose of 800 mg five times daily for seven days should be prescribed on the advice of a specialist.
Informed consent should be obtained because the use of aciclovir in pregnancy is off-label.
Basis for recommendation
The recommendation to prescribe aciclovir is based on guidance issued by the British Society for the Study of Infection, Royal College of Obstetricians and Gynaecologists, and Health Protection Agency [Nathwani et al, 1998; Ogilvie, 1998; RCOG, 2007; HPA, 2011]. The Health Protection Agency and RCOG recommend use of aciclovir if the woman is more than 20 weeks pregnant and presents within 24 hours of rash onset. For women less than 20 weeks pregnant, caution is advised [RCOG, 2007; HPA, 2011].
Patient advice on aciclovir
What advice should I give to someone prescribed aciclovir?
Advise people receiving high doses of aciclovir to maintain adequate hydration. This is particularly important if the person is elderly or has renal impairment.
Aciclovir is excreted via the kidneys. Adequate hydration minimizes the risk of renal damage with high dose aciclovir treatment.
Remind the person to take the aciclovir regularly at 4-hourly intervals during the day (with an 8 hour gap overnight):
Suggested times are 7 a.m., 11 a.m., 3 p.m., 7 p.m., and 11 p.m.
If these times are not suitable, aciclovir can be taken at different times, as long as the doses are spaced at least 4 hours apart.
Reassure the person that oral aciclovir is generally well tolerated:
Gastrointestinal symptoms (for example nausea, vomiting, diarrhoea, and abdominal pain) and skin rashes (including photosensitivity and urticaria) are the most common adverse effects.
[Ogilvie, 1998; Heininger and Seward, 2006; ABPI Medicines Compendium, 2011b; BNF 64, 2012]
Evidence
Evidence
Search strategy
Scope of search
A literature search was conducted for guidelines, systematic reviews and randomized controlled trials on primary care management of chickenpox, with additional searches for evidence in the following areas:
Antihistamines (in particular chlorphenamine) for symptom relief in chickenpox.
Search dates
August 2007 - September 2012
Key search terms
Various combinations of searches were carried out. The terms listed below are the core search terms that were used for Medline and these were adapted for other databases. Further details are available on request.
exp Chickenpox/, chickenpox.tw., chicken pox.tw., varicella.tw.
exp Histamine Antagonists/, antihistamine$.tw., exp Chlorpheniramine., chlorphenamine.tw., chlorpheniramine.tw.
Table 1. Key to search terms.| Search commands | Explanation |
|---|---|
| / | indicates a MeSh subject heading with all subheadings selected |
| .tw | indicates a search for a term in the title or abstract |
| exp | indicates that the MeSH subject heading was exploded to include the narrower, more specific terms beneath it in the MeSH tree |
| $ | indicates that the search term was truncated (e.g. wart$ searches for wart and warts) |
Sources of guidelines
National Institute for Health and Clinical Excellence (NICE)
Scottish Intercollegiate Guidelines Network (SIGN)
Royal College of General Practitioners
National Guidelines Clearinghouse
Guidelines International Network
NHS Scotland National Patient Pathways
Agency for Healthcare Research and Quality
Institute for Clinical Systems Improvement
National Health and Medical Research Council (Australia)
Royal Australian College of General Practitioners
British Columbia Medical Association
University of Michigan Medical School
Michigan Quality Improvement Consortium
National Resource for Infection Control
UK Ambulance Service Clinical Practice Guidelines
RefHELP NHS Lothian Referral Guidelines
Medline (with guideline filter)
Driver and Vehicle Licensing Agency
NHS Health at Work (occupational health practice)
Sources of systematic reviews and meta-analyses
Systematic reviews
Protocols
Database of Abstracts of Reviews of Effects
Medline (with systematic review filter)
EMBASE (with systematic review filter)
Sources of health technology assessments and economic appraisals
NIHR Health Technology Assessment programme
NHS Economic Evaluations
Health Technology Assessments
Canadian Agency for Drugs and Technologies in Health
International Network of Agencies for Health Technology Assessment
Sources of randomized controlled trials
Central Register of Controlled Trials
Medline (with randomized controlled trial filter)
EMBASE (with randomized controlled trial filter)
Sources of evidence based reviews and evidence summaries
Central Services Agency COMPASS Therapeutic Notes
Sources of national policy
Health Management Information Consortium (HMIC)
Patient experiences
Patient.co.uk - Patient Support Groups
Sources of medicines information
The following sources are used by CKS pharmacists and are not necessarily searched by CKS information specialists for all topics. Some of these resources are not freely available and require subscriptions to access content.
British National Formulary (BNF)
electronic Medicines Compendium (eMC)
European Medicines Agency (EMEA)
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