Seroprevalence And Molecular Detection Of Chikungunya Virus Among Febrile Outpatients Seeking Health Care In Mzuzu City, Malawi

ABSTRACT

Chikungunya is a viral disease caused by Chikungunya virus (CHIKV) that is transmitted to humans by infected Aedes aegypti and Ae. albopictus mosquitoes. The objective of this study was to determine the seroprevalence of Chikungunya infection among febrile patients seeking healthcare in Mzuzu City, Malawi. Blood samples were collected during 2019 from outpatients attending Mzuzu Central Hospital who presented with fever but who were malaria and sepsis negative. Sera from outpatients were transported to the University of Malawi for analysis of the presence or absence of CHIKV specific immunoglobulin M (IgM) antibodies and CHIKV ribonucleic acid (RNA). Enzyme- linked immunosorbent assay (ELISA) was used to detect anti-CHIKV IgM antibodies while one step reverse transcription-polymerase chain reaction (RT-PCR) was conducted in IgM positive sera in order detect the presence of CHIKV RNA. Out of 119 CHIKV-suspected samples, 73 (61.3%) tested positive for anti-CHIKV IgM antibodies by ELISA. When 14 of the IgM seropositive sera were randomly selected and screened using RT-PCR, they were all positive for CHIKV RNA. This study has therefore provided an insight of current seroprevalence of Chikungunya and circulation of CHIKV among the human population in Mzuzu city, Malawi. These results suggest an active circulation of CHIKV in the population, therefore accurate laboratory assays are highly recommended for CHIKV diagnosis and appropriate management of febrile patients.