Overview and evaluation of the results of West Nile Virus monitoring in Hungary-Serbia ipa project BirdPROTECT

Abstract

West Nile virus (WNV) is a vector-borne zoonotic virus that has a major impact on wild birds and human health. Wild birds play an important role as reservoir hosts and since they do not know state borders they can carry the virus over long distances. The aim of this study was to monitor and detect the spread of WNV in the population of wild birds in special nature reserves with water based habitats in Hungary (Bács-Kiskun county and Baranya county) and Serbia (Vojvodina Province). A total of 1347 samples (cloacal and pharyngeal swabs, feces and carcasses) of wild birds were tested for the presence of WNV RNA by real-time RT-PCR method, 747 samples in Hungary and 600 samples in Serbia. Many different bird species were tested including aquatic birds, song birds, corvids, pigeons, raptors, woodpeckers, gallinaceous birds. The presence of WNV RNA was detected only in Serbia, in 12 samples from 9 different locations and in 6 different species, mainly raptors and corvids. There was no evidence of WNV circulation in wild birds from Hungary in examined locations. Although there were no positive samples detected in cross border region of Hungary, there were positive samples detected in several cross border locations in Serbia, which suggests that WNV is circulating in the population of wild birds. Infected bird movement is one of the key factors for introducing WNV to the new areas. Timely detection of WNV in reservoir hosts and early warning of public health institutions can improve the living conditions of the population in the region by preventing the potential outbreaks and negative effects of zoonotic WNV on both animals and people.