A Rapid Epidemiological Tool to Measure the Burden of Norovirus Infection and Disease in Resource-Limited Settings.

BACKGROUND:Rapid, cost-effective tools are needed to estimate the disease burden of acute gastroenteritis (AGE) and norovirus (NoV) in resource-limited settings. METHODS:Households with children (6 weeks-17 years) in rural Guatemala were randomly enrolled into 2 parallel AGE surveillance systems: (1) a prospective cohort, which included an enrollment visit followed by 1 year of prospective observation using a smartphone-based weekly symptom diary; and (2) 2 sequential cross-sectional rapid active sampling (RAS) surveys. Norovirus testing was performed during enrollment (all subjects) and for prospective AGE episodes (prospective cohort only). RESULTS:The prospective cohort enrolled 207 households (469 children) from April to September 2015 followed by 471 person-years of observation; RAS survey 1 enrolled 210 households (402 children) during October to November 2015, and RAS survey 2 enrolled 210 separate households (368 children) during January to February 2016. The prospective cohort detected a NoV+ AGE prevalence of 11% and a population-attributable fraction (PAF) of -1.6% at enrollment, followed by an incidence of 1.4 episodes/100 person-years. Rapid active sampling surveys 1 and 2 identified a NoV+ AGE prevalence of 14%-21% and a PAF of 3.2%-12.4%. CONCLUSIONS:Rapid active sampling surveys were practical and identified more cases of NoV infection and disease compared with a parallel prospective cohort in rural Guatemala.