Burden of Viral Gastroenteritis in Children Living in Rural China: Population-Based Surveillance

Background: Viral diarrhea is a major public health problem among Chinese children. Despite established disease burden, rotavirus vaccine has not been introduced into routine national immunization; vaccines against norovirus are being developed without complete understanding of gastroenteritis epidemiology. To bridge this knowledge gap, we investigated the disease burden of viral gastroenteritis in rural China. Methods: Between October 2011 and December 2013, population-based active and passive surveillance was conducted in Zhengding and Sanjiang counties in the north and south of China, respectively. Diarrhea stools were collected from children <5 years of age. All specimens were tested for rotaviruses, noroviruses, sapoviruses, enteric adenoviruses, and astroviruses by polymerase chain reaction. The severity of illness was assessed using the Vesikari Score System. Results: During the study period, the overall incidence of diarrhea was 215.0 and 398.2 cases/1,000 children/year in Zhengding and Sanjiang counties, respectively. The most common pathogen was rotavirus (54.7 vs 45.6 cases/1000 children/year in Zhengding and Sanjiang, respectively), followed by norovirus (28.4 vs 19.3 cases/1000 children/year in Zhengding and Sanjiang, respectively). The highest incidence of these viruses was observed in children 6-18 months of age. Among the 5 viral pathogens, rotaviruses caused the most severe illness, followed by noroviruses. Conclusion: Rotavirus and norovirus are the 2 most important viral pathogens causing childhood diarrhea in both northern and southern China; they should be the major targets for viral gastroenteritis prevention strategies among children in China. Funding: This work was supported by the National Science and Technology Major Projects for Significant New Drugs Development (2018ZX09201007). Declaration of Interest: The authors declare that they have no competing interests. Ethical Approval: This study was reviewed and approved by the Institutional Review Board (IRB) of the Hebei CDC and the Guangxi CDC, as well as the IRB of the Institutes of Biomedical Sciences, Fudan University. Written inform consent was obtained from a parent/guardian of each child. The study was performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.