Seroprevalence of Neutralizing Antibodies to West Nile Virus (WNV) among Patients with Pyrexia of an Unknown Origin (PUO) In Maiduguri, Borno State, Nigeria

The seroprevalence of West Nile Virus (WNV) infection was determined in 200 patients with pyrexia of an unknown origin using the virus micro-neutralization test (micro-VNT). The patients consisted of 104 (52%) males and 96 (48%) females attending clinics at the University of Maiduguri Teaching Hospital (UMTH) Maiduguri, Borno State. The patients are in the age range of 3 years to 70 years, with mean (±SD) age of 25.4 ±13.4 years. Of the 200 patients tested, 19 had neutralizing antibodies to WNV, giving an overall seroprevalence of 9.5% in the study area. The age distribution of positive sera were as follows: In the age group of 31-35 years, (25.0%), followed by 21-25 years, (13.9%), 6-10 and >50 years, with 11.8% and 11.1% respectively. However, no detectable neutralizing antibodies to the WNV were found in the age groups of 11-15 years and 36-50 years. The seroprevalence rates according to the different age groups did not differ significantly (p=0.318). Thirteen (12.5%) of the 19 positive sera were from males while 6 (6.3%) were from females, however, the difference in prevalence was not statistically significant (p=0.153) according to gender of the study population.

Keywords: West Nile Virus, Neutralizing Antibodies, Humans, Maiduguri, Nigeria;