Complications of varicella: varicella-associated cerebritis in a child. Case report and review

Low vaccine coverage and varicella outbreaks in Brazil - 2019-2022

The persistence of varicella outbreaks in Brazil has underscored the high concern with the low vaccine coverage in the last 4 years. Using publicly available data from the Brazilian Health System (SUS), this study analyzed varicella vaccine coverage and incidence trends from 2019 to 2022 in Brazilian States. Vaccine coverage decreased nationally in 2020, possibly influenced by the COVID-19 pandemic's initial phase. In Bahia State, we have the persistence of varicella with an incidence rate of 3.0 cases per 100,000 inhabitants (higher incidence compared to other States) in 2023. Under 15 months children and young children (4-6 Years old) faced the highest risk, urging the importance of vaccination. Despite a monovalent varicella vaccine being available through Brazil's National Immunization Program (NIP), Bahia fell short of achieving the ≥95 % disease control target for coverage. The study highlight the importance of vaccines to prevent some infectious diseases, as varicella, in poor tropical regions. Addressing vaccine hesitancy and misinformation, and augmenting awareness campaigns, are important to achieve and sustain high vaccine coverage over 80% as WHO guidelines to obtain a safe rate of protection for Brazilian population (Brazil's national immunization program has a target of 95% coverage).

Neurologic varicella complications before routine immunization in Germany

Varicella is an acute febrile, highly infectious disease. We describe the incidence and types of neurologic complications in children up to 16 years old. Hospitalized varicella cases were prospectively captured by active nationwide surveillance through the German Pediatric Surveillance Unit for Rare Diseases from January 2003 to December 2004. Neurologic complications occurred in 232 (25.4%) of 918 hospitalized children with varicella, and were the most frequent reason for hospitalization. The median age was 4.2 years (interquartile range 2.5-5.9). The median duration of hospital stay was 6 days (interquartile range 3-11). Neurologic complications were more frequent (P=0.054) in immunocompetent (32%) than immunocompromised (4%) children. The most frequent diagnoses comprised acute cerebellar ataxia in 72 (31.0%), febrile convulsion in 69 (29.7%), meningoencephalitis in 52 (22.4%), cerebral convulsions in 21 (9.1%), syncope in 9 (3.9%), and cerebral vasculitis/infarction in 6 (2.6%) of all children with neurologic complications. Twenty-eight (12%) demonstrated sequelae (18 with ataxia, four with epilepsy, two with hemiparesis, three with cerebral nerve palsy, and one with dysesthesia). Three patients died. The yearly incidence of neurologic varicella-associated hospitalizations was estimated at 2.4 neurologic complications per 100,000 children, corresponding to about one neurologic complication in 2000 varicella cases.