Seroprevalence of Mumps among Patients Attending Selected Hospitals in Kenya

Background: Mumps is a highly infectious viral disease that poses a significant public health concern despite presence of safe and effective vaccine. This study aimed to determine seroprevalence of mumps among patients attending selected hospitals in Coast and Central regions of Kenya, and to evaluate the demographic factors associated with mumps seropositivity. Methodology: This was a cross-sectional study where serum samples collected from patients attending Kiambu, Murang’a and Kilifi County hospitals were quantitatively tested for anti-mumps IgG antibodies using commercial enzyme linked immunosorbent assay (ELISA) kits. Sample size estimation was calculated using Cochran formula. A total of 451 volunteers were enrolled between October 2020 and November 2021. Ethical approval was obtained from Institutional Review Board of Kenya Medical Research Institute Scientific and Ethics Review Unit. Statistical analyses were conducted using Statistical Package for the Social Sciences (SPSS) version 23.0 software. Results: The overall mumps seropositivity rate was 90.5% and geometric mean of mumps IgG titers (GMT) was 401.3 U/ml. Both seroprevalence and GMT were not significantly influenced by the demographic factors of the population under study. Nonetheless, there were trends of higher prevalence related to certain demographic groups. Seroprevalence increased with increasing age from 85% for less than 10-year-olds to 100% among those aged between 60 and 69 years (P=.779). Similarly, females had a higher prevalence at 91.5% compared to 88.6% among males (P=.063). Also, the population from the central region of Kenya had a seroprevalence of 92% compared to 87.3% at the coast region (P=0.249) and rural residents reported 91.3% compared to 88.5% in urban residents (P=.607). Conclusions: The high mumps seroprevalence in this Kenyan population reflects widespread natural infection in the absence of vaccination. Age-related increases in antibody prevalence and geometric mean titres indicate cumulative exposure over time. These findings provide essential pre-vaccine baseline data and support the need for strengthened mumps surveillance and consideration of mumps vaccine inclusion in Kenya’s national immunization program.