Burden of acute gastroenteritis caused by norovirus in China: A systematic review

Summary Background To understand the epidemiology and disease burden of norovirus (NoVs) gastroenteritis in China, a systematic review was conducted. Methods Studies on acute gastroenteritis (AGE) caused by NoVs from mainland China, published before 2017 were searched. All retrieved articles were screened and reviewed by a standardized algorithm. NoVs detection rates as well as strain variations by ages, seasonal variations and geographic locations were analyzed using random-effects model. Results A total of 225 articles were included in the final analysis. Similar detection rates at 21.0% and 19.8% were obtained from the North and the South, respectively. NoVs infection occurred year round, with a peak between October and January in the North and between August and November in the South. High detection rates (∼29%) of NoVs were found in adults and the elderly and in children aged 6–35 months (∼22%). The predominant strains were GII.4 (70.4%), followed by GII.3 (13.5%). Conclusion NoVs cause significant disease burden in China which warrants development of vaccines against NoVs, particularly for children and the elderly who are vulnerable to gastroenteritis diseases. To achieve a broad protection, continual monitoring NoV epidemics and strain variations for selection of proper vaccine strains is critical.