Objectives: To describe and compare the incidence and spectrum of complications of varicella pre-vaccine and post-vaccine licensure.
Methods: We performed a retrospective chart review of children under age 21 years either treated in the emergency department (ED) or admitted to the hospital with varicella at Children's Hospital, Boston, from January to December 1994 (pre-licensure) and from January 1996 to December 1997 (post-licensure).
Results: We identified 937 children who made a visit to the ED for varicella and 270 children hospitalized for varicella during the 3-year study period. The ratio of varicella-related visits to the ED to total visits (0.67%) did not vary significantly from the post-vaccine ratio (0.60%). The most common reasons for a visit were cellulitis in immunocompetent patients and treatment with varicella zoster immune globulin (VZIG) in children with immunosuppression. Similarly, the ratio of varicella-related hospitalizations to total hospitalizations did not vary in the pre-vaccine (0.53%) and post-vaccine (0.47%) eras. The most common complications in hospitalized patients were cellulitis in previously healthy children (37%) and uncomplicated varicella in immunocompromised patients (36%). The distribution of diagnoses in the ED and complications among hospitalized children did not differ significantly in the pre-vaccine and post-vaccine eras.
Conclusions: Despite licensure of the varicella vaccine, varicella-related hospitalizations and ED visits have not changed significantly. Further efforts are needed to increase utilization of the varicella vaccine.