West Nile Virus Seroprevalence among Qatari and Immigrant Populations within Qatar

Abstract

Background: West Nile virus (WNV) is one of the most widely spread arboviruses worldwide and a highly significant pathogen in humans and animals. Despite frequent outbreaks and endemic transmission being reported in the Middle East and North Africa (MENA), seroprevalence studies of WNV in Qatar are highly lacking. Aim: This study aims to investigate the actual prevalence of WNV among local and expatriate communities in the Qatar using a large sample size of seemingly healthy donors. Method: A total of 1992 serum samples were collected from donors of age 18 or older and were tested for the presence of WNV antibodies. Serion enzyme-linked immunosorbent assay (ELISA) commercial microplate kits were used to detect the presence of the WNV IgM and IgG. The seropositivity was statistically analyzed using SPSS software with a confidence interval of 95%. Results: The seroprevalence of anti-WNV IgG and IgM in Qatar was 10.3% and 3.4%, respectively. The country-specific seroprevalence according to nationality for WNV IgG and IgM, respectively, were Sudan (37.0%, 10.0%), Egypt (31.6%, 4.4%), India (13.4%, 3.2%), Yemen(10.2%, 7.0%), Pakistan (8.6%, 2.7%), Iran (10.6%, 0.0%), Philippines (5.4%, 0.0%), Jordan(6.8%, 1.1%), Syria (2.6%, 9.6%), Palestine (2.6%, 0.6%), Qatar (1.6%, 1.7%), and Lebanon (0.9%, 0.0%). The prevalence of both IgM and IgG was significantly correlated with the nationality (p≤0.001). Conclusion: Among these tested nationalities, Qatar national has a relatively low burden of WNV disease. The highest prevalence of WNV was found in the Sub Saharan African nationalities like Sudan and Egypt. The seroprevalence of WNV is different from the previously reported arboviruses such as CHIKV and DENV, which was highest among Asian countries (India and Philippines). Further confirmatory tests such as viral neutralization assays are needed to confirm the IgM seropositivity in these samples since these samples could be a source of viral transmission through blood donation.