On the potential roles of ticks and migrating birds in the ecology of West Nile virus

Abstract

Background: Mosquitoes are the primary vectors of West Nile virus (WNV). Ticks have, however, been suggested to be potential reservoirs of WNV. To investigate their role in the spread of the virus, ticks, which had been collected from birds migrating northward from Africa to Europe, were analyzed for the potential presence of WNV RNA. Methods: On the Mediterranean islands of Capri and Antikythira, a total of 14,824 birds were captured and investigated from which 747 ticks were collected. Results and conclusions: Most of the identified ticks (93%) were nymphs and larvae of Hyalomma marginatum sensu lato (s.l.), most of which were or appear to be Hyalomma rufipes. Of these ticks, 729 were individually screened for WNV RNA. None of the ticks was found to be WNV positive. Thus, there was no evidence that H. marginatum s.l. ticks play a role in the spread of WNV from Africa to Europe.

Keywords

• West Nile virus
• emerging infectious diseases
• migratory birds
• zoonoses
• ticks
• Hyalomma marginatum s.l.
• Hyalomma rufipes