Seroprevalence and risk factors of West Nile virus infection in veterinarians and horses in Northern Palestine

Abstract

Background and Aim: West Nile fever (WNF) is a neurotropic, mosquito-borne disease affecting humans and domesticated animals, caused by a member of the genus Flavivirus. Over the last decades, this virus has been responsible for several cases of illness in humans and animals. The current epidemiological status of WNF in horses is insufficient, and in veterinarians, as an occupational hazard is unknown. This study aimed to investigate and determine the seroprevalence and risk factors for WNF in veterinarians and horses in Palestine. Materials and Methods: In this study, serum samples from 100 veterinarians and 87 horses were collected between August 2020 and September 2020 from different cities of Northern Palestine. West Nile virus (WNV) antibodies were detected using an enzyme-linked immunosorbent assay. Results: Our results showed that 60.9% of the horse serum samples were positive in all investigated cities. In horses, location is a risk factor for the seropositivity for WNF, whereas age, sex, breed, and intended use of the horses, were not associated with increased WNF seropositivity. In veterinarians, 23.0% of the serum samples were positive. Positive samples were detected in all locations, age groups, experience length, and work sectors. However, the seropositivity for WNF was not influenced by these variables. Conclusion: The results revealed that WNV circulates in most regions of Palestine. Our results will help determine the risk of infection in animals and humans and control WNV transmission. Surveillance studies on humans, vectors, and animals are needed to better define endemic areas.

West Nile Virus Infection in Occupational Settings—A Systematic Review

“…Farmers, agricultural workers, veterinarians and in general jobs in contact with birds and farm animals have also been identified as occupational groups at higher risk for WNV infection. Alzuheir et al [ 23 ] detected a 23.0% WNV seroprevalence among veterinarians in Palestine, which was much higher than that observed in other non-occupational groups from other studies where seropositivity was not associated with either sector of work. Although horses are ‘dead-end’ hosts which do not sustain the circulation of the WNV in nature, veterinarians in the equine specialty have been suggested as the first sentinel of human cases in WNV-infected horses’ areas.…”

“…( Table 3 ). Moreover, the study by Dorko et al [ 25 ] and Alzuheir et al [ 23 ] showed a probably high risk of bias in more than two of the domains. Overall, however, the studies make it possible to adequately assess the results obtained from the literature review.…”

“…Among the recruited individuals, 46.6% showed IgG against WNV, suggesting that soldiers can act as a sentinel population to assess the presence of WNV in a specific area. In the study by Alzuheir et al (2021) [23], serum samples from 100 veterinarians and 87 horses were collected between August and September 2020 from different cities in Northern Palestine. WNV IgG antibodies showed positive results for 60.9% of horse serum samples and 23.0% of veterinarians' serum samples, the last not influenced by location, age, experience length and characteristics of working activities.…”

No evidence of Rift Valley fever antibodies in veterinarians and sheep in Northern Palestine

“…More than 53 mosquito species have been identified as possible vectors for RVFV [26], including Phlebotomus papatasi and Aedes albopictus in Palestine [27,28]. These vectors are related to the endemic circulation of other arboviral diseases in Palestine, like West Nile fever in humans and animals, and bluetongue in ruminants [29,30]. Controlling such a disease requires a strategy like the One Health approach, which involves understanding and managing the animal, human, and environmental determinants of the disease [10].…”

“…Understanding the factors responsible for the absence of RVFV could provide valuable information to prevent and control the disease in a region infested by the vector but lacking the virus [25]. Our findings provide a baseline for future prediction and early warning systems for RVFV emergence.< Spatial and temporal surveillance of the vectors and susceptible animals will facilitate early warning [25][26][27][28][29][30][31][32].…”