A Survey on West Nile and Usutu Viruses in Horses and Birds in Poland.

Barbara Bażanów,Agnieszka Frącka,Janusz Pawęska,Petrus Jansen Van Vuren,Roland Kozdrowski,Dominika Stygar,Piotr Szymański,Jan Twardoń

doi:10.3390/v10020087

Abstract

West Nile virus (WNV) and Usutu virus (USUV) are members of the family Flaviviridae which, natural life cycles involve mosquito–bird–mosquito transmission. Both represent emerging viruses in Europe with potential to cause neuroinvasive disease in humans. This study investigates the seroprevalence of serum neutralizing antibodies to WNV and to USUV in birds and in horses in Poland. Antibodies against WNV and USUV were detected in 5 (35.7%) and in 1 (7.14%) of 14 birds and in 62 (15.08%) and in 115 (27.98%) of 411 horses, respectively. Twenty-one WNV serologically positive horses (33.87%) and 67 USUV serologically positive horses (58.26%) did not travel outside Polish borders. Given the high abundance of potentially competent mosquito species in Poland, high populations of horses and different bird species, our findings highlight implementation of active control programs, including monitoring of geographic spread and dynamics of WNV and USUV transmission in both primary and accidental hosts. It is also important to improve public health awareness about the disease these viruses may cause.

Highlights

West Nile virus (WNV) and Usutu virus (USUV) are mosquito-borne zoonotic agents belonging to the genus Flavivirus, family Flaviviridae [1,2]
We investigated the seroprevalence of serum neutralizing antibodies to WNV and USUV in birds and horses in Poland
Virus neutralizing antibodies to WNV were detected in 62 horses of 411 tested (15.08%)

Summary

Introduction

West Nile virus (WNV) and Usutu virus (USUV) are mosquito-borne zoonotic agents belonging to the genus Flavivirus, family Flaviviridae [1,2]. WNV was first isolated in 1937 in the West Nile region of Uganda from a patient suffering a mild febrile illness [3,4]. In 1999 WNV, was introduced into the United States where it caused severe epidemic of meningoencephalitis in New York City. It spread throughout Canada, Central America and the Caribbean [11]. Previous serological surveys in Poland showed low seroprevalence of WNV antibodies in wild birds, horses and humans [3,12,13,14]. It is rather surprising that results of recent study in humans indicate high exposure to WNV [14]

Methods

Results

Conclusion