Rotavirus is the leading cause of severe diarrhea in young children globally, but the extent to which it affects older children and adults is uncertain. This is an important gap in knowledge, as estimates of rotavirus in these older populations are needed to accurately understand the spread and severity of rotavirus globally. The START team was asked to conduct a systematic review and meta-analysis to quantify the proportion of diarrhea cases due to rotavirus among persons five years and older and to estimate this proportion by age strata. We followed PRISMA guidelines (e.g., double screening of all articles) to identify all published articles in the English language with information on proportion of diarrhea due to rotavirus among adults or children 5-years or older. We included articles that were published in 1990 or later, used lab-confirmation for rotavirus cases, reported on at least 100 symptomatic individuals in the study population of interest (people ≥5 years old), and collected data for at least one calendar year. Through this process, we identified 4,994 abstracts, of which 66 articles were included in the final systematic review and meta-analysis. Articles came from 32 countries, including low, middle, and high-income countries.
We abstracted all relevant data from these articles and calculated pooled prevalence using inverse variance weighting and random effects and summarized prevalence of rotavirus by age group, geography, study type, and time period. The results showed there was large heterogeneity in reported prevalence that was unexplained by the analysis, i.e., there were no differences observed across any of the variables we examined, although there was much variation between observations. Overall, the results of our analysis supported levels of rotavirus observed by subject matter experts (SMEs) at the Gates Foundation. Details of the results can be found in the final PowerPoint slide deck.