Evidence of chikungunya virus infection among febrile patients seeking healthcare in selected districts of Tanzania Edson Kinimi1, Mariana J. Shayo1, Patron N. Bisimwa1,N.P Samuel O. Ang’wenyi1, Jacqueline Weyer2, Petrus J. van Vuren2, Janusz T. Paweska2,3, Leonard E.G. Mboera3,4, Mark M. Rweyemamu1,3 and Gerald Misinzo1,3 1
Department of Microbiology, Parasitology and Immunology, College of Veterinary and Medical
Sciences, Sokoine University of Agriculture, P. O. Box 3019, Morogoro, Tanzania 2
Center for Emerging, Zoonotic and Parasitic Diseases, National Institute for Communicable
Diseases of the National Health Laboratory Services, Private Bag X4, Sandringham 2131, Republic of South Africa 3
SACIDS African Centre of Excellence for Infectious Diseases of Humans and Animals in
Southern and Eastern Africa, Sokoine University of Agriculture, P. O. Box 3297, Morogoro, Tanzania 4
National Institute for Medical Research, 3 Barack Obama Drive 11101, P. O. Box 9653, Dar es
Salaam, Tanzania
Corresponding author: Prof. Gerald Misinzo, SACIDS African Centre of Excellence for Infectious Diseases of Humans and Animals in Southern and Eastern Africa, Sokoine University of Agriculture, Department of Microbiology, Parasitology and Immunology, College of Veterinary and Medical Sciences, Sokoine University of Agriculture, P. O. Box 3297, Morogoro, Tanzania Tel: +255767058805; E-mail:
[email protected];
[email protected]
Email addresses of all authors: Edson Kinimi (
[email protected]), Mariana J. Shayo (
[email protected], Patron N. Bisimwa (
[email protected]), Samuel O. Ang’wenyi (
[email protected]), Jacqueline Weyer (
[email protected]), Petrus J. van Vuren (
[email protected]), Janusz T. Paweska (
[email protected]), Leonard E.G. Mboera (
[email protected]), Mark M. Rweyemamu (
[email protected]) and Gerald Misinzo (
[email protected])
Abstract Background: Chikungunya virus (CHIKV) infection is an emerging mosquito-borne disease that has been associated with frequent epidemics in Sub-Saharan Africa and South-East Asia. However, there is dearth of data on its magnitude and associated risk factors in Tanzania. This study was conducted to determine the seroprevalence of CHIKV among febrile patients seeking medical care from health facilities in selected districts of Tanzania. Methods: This cross-sectional health facility-based study was carried out in Karagwe, Sengerema, Kilombero and Kyela districts of Tanzania. Human sera were collected from patients who were recruited amongst outpatient febrile subjects. The sera were tested for the presence of CHIKV-specific immunoglobulin M (IgM) and IgG antibodies using enzyme-linked immunosorbent assay (ELISA). Patient’s data on clinical and socio-demographic characteristics were collected using a structured questionnaire. Results: A total of 728 patients (mean age=28.76 years) were involved in this study. Out of 728 serum specimens analyzed, 105 (14%) had IgG and 11 (1.5%) had IgM antibodies to CHIKV. The most affected age group was 20-29 years. The overall mean seroprevalence of CHIKV was 16%. The seroprevalence was significantly higher among patients in Karagwe (29.7%) followed by Sengerema (13.2%), Kilombero (11.5%) and Kyela (9.3%). The common clinical manifestations associated with CHIKV infection were fever (100%), headache (70%) and joint pain (68.25%). Conclusions: Our results indicate that CHIKV infection is prevalent and contributes to the burden of febrile illnesses in Tanzania. The seroprevalence varies between districts. It is recommended that febrile patients be screened for CHIKV and other mosquito-borne infections in order to provide appropriate healthcare.
Keywords: chikungunya, febrile illness, vector-borne, emerging, seroprevalence, Tanzania