Absence of Serological Evidence of West Nile Virus in Blood Donors in South Western Nigeria

Background: West Nile virus (WNV) is a mosquito-borne virus that circulates among avians, but can also affect other species, particularly humans and horses. The virus is transmissible via blood transfusion. Objectives: To determine the prevalence of the West Nile virus among blood donors in Nigeria.Materials and Methods: Serum samples from 185 blood donors who donated blood at blood bank units of Obafemi Awolowo University Teaching hospitals and Ladoke Akintola University Teaching Hospital, Nigeria were screened for WNV IgM antibody.Results: Out of the 185 donors recruited for the study, 175 (94.6%) were males. The age of the participant ranges from 18 – 65 years with the mean age (SD± 20.3). One hundred and sixty five (89.1%) donors are urban dwellers while twenty (10.8%) donors are rural dwellers. Twenty seven donors (15.4%), out of the urban group regularly use insecticides treated or mosquito repellant nets whereas none of the rural dwellers use insecticides or mosquito net. All the 185 donors screened were negative for West Nile virus- specific IgM antibody.Conclusion: This study reveals that there is no serological evidence of WNV infection in Osun state Nigeria. Although this is only a preliminary report, there would be the need for a more elaborate study cutting across different seasons of the year on the prevalence of WNV in Nigeria.Keywords: West Nile virus, blood donors, serological evidence, IgM antibody, Nigeri