Severe varicella complications in hospitalized children and adolescents in central Switzerland, 2010-2020

Abstract

AIM: Recent data on morbidity and mortality of hospitalized children of all age groups due to varicella are missing in Switzerland during a period where universal varicella vaccination (UVV) had not yet been introduced. The aim of the study therefore was to generate such data prior to a potential UVV recommendation by the Swiss national health authority.

METHODS: Retrospective case cohort study of children hospitalized with varicella between 2010 and 2020 at a tertiary children’s hospital in central Switzerland, serving around 10 % of the Swiss population. Inclusion criteria were either acute varicella and/or related complications.

RESULTS: 95 patients were identified. The median age at onset was 4 years (range 2 months to 13 years) with a peak of patients between 1-4 years. 53 had mild or moderate and 42 patients had severe varicella-associated complications (8 had > 2 severe complications). The most common severe complications were bacterial skin and soft tissue infections (n=28), invasive secondary bacterial infections (n= 18), and central nervous system related complications (n=12). Admission to the paediatric intensive care unit and surgical intervention were required in 11 and 16 patients, respectively. Two previously healthy school age children died due to secondary bacterial infections.

CONCLUSION: Our results demonstrate and confirm that varicella can cause severe and even fatal complications in children living in a highly developed country. This study provides valuable morbidity and mortality data from a large catchment area of Switzerland facilitating future data comparison of children before and after the introduction of UVV in Switzerland.