Prevalence and Risk Factors for Rotavirus Infection Among Under-fives in Sub-saharan Africa - a Systematic Review and Meta-analysis

Abstract

Study Background: Rotavirus plays a significant role in severe diarrhea and associated mortality among children under five, particularly in countries with low and moderate incomes. In Sub-Saharan Africa, rotavirus accounts for higher than half of global children mortality and 42% of all diarrheal disease hospitalization annually. While studies have been conducted on rotavirus in the region, there is lack of clarity on the overall burden of rotavirus diarrhea as well as key drivers of the disease in the region. Broad Objective: The research project aims to study the prevalence and risk factors for rotavirus infection in under-fives. Methodology: Systematic review and meta-analysis were conducted for studies published between 2000 to 2022 to calculate pooled prevalence and odds ratios with their 95% CI and provide a summary estimate. A random effects model was used to account for study heterogeneity and I2 statistic used to measure heterogeneity and give an estimate of the proportion of the variance in results in several studies that is attributable to actual differences rather than random variation. The prevalence and odds ratios for each risk factor were then displayed in forest plots, with the size of each box representing the weight of the study and the mean effect in the center. Results: A total of 88 out of 1141 papers identified were found to be eligible for assessment of prevalence of rotavirus among under-fives in Sub-Saharan Africa while 49 out of 1289 studies were included in risk factors analysis. An overall pooled prevalence of 31% (95% CI: 27% - 35%) and 24% (95% CI: 21% - 28%) were obtained for pre and post vaccine introduction respectively. Southern Africa registered the highest prevalence at 28% after vaccine introduction, with Central Africa recording the lowest (21%). Age was the only risk factor that was found to be statistically significant. Children below 12 months were found to have the highest risk of rotavirus infection xii i.e., they had 1.5 times the risk of rotavirus infection compared to those between 12-23 months (OR=1.48; CI= [1.13-1.95]) and four times the risk compared to those above 24 months (OR=4.15; CI= [2.74-6.29]). Conclusion: This meta-analysis underscores the significant burden of rotavirus infection among children under 5 years in Sub-Saharan Africa, with prevalence rates remaining alarmingly high despite the introduction of the rotavirus vaccine. This highlights the urgent need for enhanced vaccine supply and improved vaccination coverage, especially in countries with high birth rates that have yet to introduce the vaccine due to logistical challenges