Chickenpox (varicella) is a common and highly contagious viral illness caused by varicella-zoster virus (VZV). Although chickenpox can occur at any age even in neonates, most cases are usually seen between the ages of 2-10 years.
Signs and symptoms
Prodromal symptoms begin 24-48 hr before the rash as fever, malaise, anorexia, headache, and occasionally mild abdominal pain; these symptoms usually resolve within 2-4 days after the rash.
Varicella lesions often appear first on the scalp, face, or trunk. Initial exanthem consists of intensely pruritic erythematous macules that evolve through the papular stage to form clear, fluid-filled vesicles. While the initial lesions are crusting, new crops form on the trunk and then the extremities; the simultaneous presence of lesions in various stages of evolution is characteristic of varicella (polymorphic rash). The distribution of the rash is predominantly central or centripetal with the greatest concentration on the trunk and proximally on the extremities. Ulcerative lesions involving the mucosa of the oropharynx and vagina are also common.
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Diagnosis of varicella is mainly clinical, however serology: 4-fold or greater rise in VZV lgM antibodies is confirmatory of acute infection.
Management of chickenpox includes the following aspects:
1. Measures to control itching e.g.
-Antihistamines: allermine syrup or (fenistil drop in very young infants) are helpful in reducing itching.
-Local application of soothing agents: Calamine lotion twice or thrice daily may be also useful.
-Fingernails should be kept cut: This is important to prevent scratching and to avoid secondary bacterial infection.
2. Controlling fever and pain e.g. by Paracetol syrup or suppository (15mg/kg/dose 4 times daily).
3. Antiviaral treatment for complicated or disseminated varicella e.g. acyclovir, to be most effective, treatment of Varicella should be initiated as early as possible. Oral therapy with acyclovir syrup (20 mg/kg/dose; maximum: 800 mg/dose] given as 4 doses/day for 5 days.
4. Antibiotics: They are only indicated in secondary bacterial infection. Oral erythromycin (50 mg/kg/day, in 3 divided doses) or a first-generation cephalosporin as cephalexin (50 mg/kg/day, in 3 divided doses) can be used for 5-7 days.