West Nile virus infection in horses in Saudi Arabia (in 2013-2015).

This research paper discusses a study on the prevalence of West Nile virus (WNV) infection in horses in the eastern and central regions of Saudi Arabia between 2013 to 2015, noting an alarming presence of WNV antibodies in these equines.

Overview of West Nile Virus

• West Nile virus (WNV) is a concerning zoonotic arbovirus, which means it can be transmitted from animals to humans. It manifests in various clinical syndromes in both humans and horses, which range in severity.
• WNV is primarily transmitted through the bite of infected Culex mosquitoes.
• Though reported in multiple countries within the Middle East and Asia, little information is available about its prevalence in horse populations within the Arabian Peninsula.

Research Methodology and Results

• The researchers conducted a serological study, testing the blood serum of 200 horses for the presence of WNV antibodies, signifying a past infection.
• These horses were located in the Eastern and Central regions of Saudi Arabia, and their blood samples were collected from 2013-2015.
• Both a commercial enzyme-linked immunosorbent assay (ELISA) kit and microneutralization (MN) tests were utilized to detect WNV antibodies.
• The ELISA was compared with the MN test (the latter considered a “gold standard” in virus detection) and was found to have 94.7% sensitivity and 80.1% specificity.
• WNV neutralizing antibody presence varied with location, seen in 17.3% of the samples collected in Riyadh up to 55.6% in Al-Qateef.

Implications of the Study

• The detected prevalence of WNV antibodies in horses in these studied regions of Saudi Arabia suggests a notable risk of disease transmission to humans.
• Given WNV’s potential severity, this underscores the importance of being vigilant of possible WNV infection in humans and horses, especially those showing signs of central nervous system disease in Saudi Arabia.