Norovirus Infections and Disease in Lower‐Middleand Low‐Income Countries, 1997–2018

Abstract

Noroviruses are a major cause of viral gastroenteritis. The burden of the norovirus in lowresourcesettings is not well‐established due to limited data. This study reviews the norovirusprevalence, epidemiology, and genotype diversity in lower‐middle‐income countries (LMIC) andin low‐income countries (LIC). PubMed was searched up to 14 January 2019 for norovirus studiesfrom all LIC and LMIC (World Bank Classification). Studies that tested gastroenteritis cases and/orasymptomatic controls for norovirus by reverse transcription‐polymerase chain reaction (RT‐PCR)were included. Sixty‐four studies, the majority on children <5 years of age, were identified, and 14%(95% confidence interval; CI 14–15, 5158/36,288) of the gastroenteritis patients and 8% (95% CI 7–9,423/5310) of healthy controls tested positive for norovirus. In LMIC, norovirus was detected in 15%(95% CI 15–16) of cases and 8% (95% CI 8–10) of healthy controls. In LIC, 11% (95% CI 10–12) ofsymptomatic cases and 9% (95% CI 8–10) of asymptomatic controls were norovirus positive.Norovirus genogroup II predominated overall. GII.4 was the predominant genotype in all settings,followed by GII.3 and GII.6. The most prevalent GI strain was GI.3. Norovirus causes a significantamount of gastroenteritis in low‐resource countries, albeit with high levels of asymptomaticinfection in LIC and a high prevalence of coinfections