Varicella at "Casa Garrahan", 2008-2013: Assessment of postexposure prophylaxis measures.

ABSTRACT

INTRODUCTION: Casa Garrahan (CG) accommodates children with complex conditions referred nationwide; these children are seen in children's hospitals located in the Autonomous City of Buenos Aires. Varicella is a highly-contagious disease, with attack rates of up to 90% among susceptible individuals. In closed communities, the implementation of outbreak control measures is critical. OBJECTIVES: To describe the characteristics of children exposed to varicella at CG, the implemented prophylaxis measures and their effectiveness. METHODS: Prospective, cohort study. Children exposed to varicella at CG between2008 and 2013, their demographic and clinical characteristics, immunization and/or history of varicella, prophylaxis measures, and secondary attack rate were assessed. RESULTS: N 107. Fifty-three percent (n 57) were girls. Their median age was 84 months old [interquartile range (IQR) 24-144]. Ninety-five percent (n 102) had an underlying disease [hemato-oncological disease 39% (n 42); neurological disease 18% (n 19); congenital heart disease 9% (n 10); and post-operative period 65 (n 6)]. Fifty percent had some degree of immunosuppression (n 54). Twenty-nine percent (n 31) referred to have had varicella; 27% (n 29) indicated that they never had the infection; and 41% (n 44) did not recall a history of varicella. Only 3% (n 3) had been vaccinated. Based on their immune status, age and history of varicella, acyclovir was indicated as prophylaxis in 61% (n 65); immunization in 10% (n 10); and gamma globulin in 1 patient. No adverse effects were observed in relation to the different prophylaxis measures. No secondary cases were observed at 30 days. CONCLUSIONS: Implemented measures were effective to prevent secondary cases. Among healthy and immunocompromised children, prophylaxis with acyclovir was effective and well-tolerated.