Varicella & Pregnancy Dr S. Asadi Infectious diseases specialist Shahid Beheshti university of medical sciences

Epidemiology children 5 to 9 years of age, who represent 60% of all cases. Children < 15 yrs represent 90% cases By adulthood, 90%-95% of the U.S. population have antibodies to varicella. In the tropics, varicella occurs more often in adults; thus, immigrants from these areas are more likely to be susceptible than the remainder of the population at comparable ages. Between 150,000 to 200,000 cases of varicella are reported annually to the Centers for Disease Control and Prevention (CDC), representing 4%-6% of all cases.

Mode of Transmission Person to Person: Direct contact with vesicular fluid or via aerosolized respiratory droplets Need airborne and contact precautions

Incubation period Typically, 14-16 days with a range of 10-21 days May be prolonged in Immunocompromised patients and those that have received VZIG Incubation period may be up to 28 days with VZIG

Period of communicability 2 days before the onset of rash through 5-6 days after onset of rash or when lesions crust over Immunocompromised patients are probably contagious during the time when new lesions are appearing

Clinical presentation Prodrome: Fever and malaise x1-2 days usually only in adults Rash: generalized, pruritic rapidly progresses from macules to papules to vesicles; usually progresses from head on down. Zoster: vesicular eruption generally unilaterally in dermatomal distribution. Most often in truncal area or CN V; Pain.paresthesia my precede rash

ZOSTER

Congential Varicella Syndrome Occurs with maternal infection with VZV in the first trimester especially 8-12 wks Cicatricial scarring of skin most common manifestation Other Manifestations: Chorioretinitis Microphthalmia congenital cataracts hypoplastic limbs mental retardation early death Cutis Aplasia

Disseminated Varicella in the newborn Newborn at very high risk if mother develops rash of Primary varicella five days before or within 48 hrs after delivery Severe infection in 17-30% and estimated case fatality rate of 31% in first 5-10 days

Diagnostic Tests ACTIVE DISEASE: Direct Flourescent Antibody for VZV: from vesicle scraping; more rapid and sensitive than culture IMMUNE STATUS: Latex agglutination for IgG to VZV: Rapid (15 minutes); very sensitive

Treatment Acyclovir (PO or IV) VZIG Should be administered as soon as possible after exposure Limited window to affect outcome of Varicella infxn due to viral replication VZIG

Acyclovir Not recommended for routine use in otherwise healthy children with varicella Oral Acyclovir should be considered in: Pts older than 12 y/o Pts with chronic cutaneous or pulm diseases Pts receiving long term ASA therapy Pts receiving short,intermittent or aerosolized courses of Corticosteroids Immunocompromised pts should always be treated with IV Acyclovir

Indications for VZIG Household: Residing in the same household Playmate: Face to face indoor play (5 min to one hour) Hospital: Varicella: same 2-4 bed room face to face contact with infectious person or visit by contagious person Zoster: Intimate contact (touching/hugging) person who is contagious Newborn infant: Primary varicella in mother 5d or less before delivery or < 48 hrs after delivery

Candidates for VZIG when significant exposure has occured Immunocompromised children with no Hx of Chicken Pox Susceptible Pregnant women Newborn infant whose mother had onset of Chicken pox within 5d before delivery or within 48 hrs after delivery Hospitalized infant >28 wks GA whose mother lacks reliable history of chicken pox or serologic evidence of immunity Hospitalized infant <28 wks GA regardless of maternal varicella Hx

Hospital Isolation Exposed susceptible patients should be placed in strict isolation from day 8 to day 21 after exposure to the patient Isolation should include contact and airborne isolation for a minimum of 5 days after the onset of rash or until the lesions crust over Pts exposed to pts who received VZIG and develop disease should be kept in isolation until day 28

Review What’s the incubation period for Varicella?? No VZIG 10-21 days VZIG 10-28 days What’s the period of communicability? 2 days before onset of rash and at least 5 days after or until lesions crust over When is the newborn at risk for Disseminated Varicella? When the mother has onset of primary varicella rash 5 days before birth or within 48 hrs after birth