Chikungunya seroprevalence in the Horn of Africa: A systematic review and meta-analysis

Background: Chikungunya virus (CHIKV) poses a significant burden on affected populations, presenting substantial challenges to public health. This study aimed to assess the seroprevalence of the CHIKV in the Horn of Africa. Methods: We conducted a systematic review and meta-analysis by searching PubMed/MEDLINE, Scopus, Scientific Direct, Google Scholar, and reference lists for primary articles published from the inception of the database until November 30, 2023. The inclusion criteria covered seroprevalence studies of CHIKV in Ethiopia, Kenya, Somalia, South Sudan, Sudan, Eritrea, Uganda, and Djibouti. Pooled seroprevalence was estimated using a random effects model, and the meta-analysis was conducted with R Studio version 4.3.1 and the Metapro package. The study protocol adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and is registered in PROSPERO, CRD42023477057. Results: From a pool of 87,567 potential studies, 34 eligible studies were included in our analysis. Most of the studies were conducted in Kenya (44%). Hospital-based studies were included in 59% of cases. A total of 23,400 participants were involved in the review. Of the 13,397 participants, 6778 (67.6% of those with information) were male. The pooled seroprevalence of CHIKV was 14% (95% CI: 9–23; I 2 = 99%). Subgroup analysis was performed. The seroprevalence was higher in studies conducted in population settings: 15% (95% CI: 5–37; I 2 = 99%) than in hospital settings. The seroprevalence of chikungunya was high from the 2004 to 2013 period, at 36% (95% CI: 13–68; I 2 = 98%). Plaque reduction neutralization tests detected 15% (95% CI: 3–49%; I 2 = 94%) of the chikungunya seroprevalence. The seroprevalence of CHIKV among inapparent infections was 17% (95% CI: 8–35; I 2 = 98%). The meta-regression analysis revealed that the chikungunya seroprevalence was predicted by the countries of study, age group, and trends of infection over time. Conclusion: Our review highlights compelling evidence of CHIKV and other arbovirus circulation in the Horn of Africa, revealing diverse seroprevalence rates across different countries, age groups, laboratory tests, clinical manifestations, and time trends. The confirmatory gold standard, the plaque reduction neutralization test, increases diagnostic accuracy.