West Nile Virus is an infectious disease that has appeared in Greece for the first time in 2010 in Central Macedonia. It is now an endemic disease, occurs almost every year and Greece accounts for about 28% of all cases at EU level (2087 out of 7406 confirmed cases).
West Nile Virus persists in the blood of wild birds (migratory and epidemic). The density of the virus in wild birds is high, resulting in a source of infection for mosquitoes, which if infected can transmit the virus to humans. In this case, one in 140 will become ill. Of the total number of recorded cases in Greece, 70% of patients have complications in the Central Nervous System.
Domestic birds have the particularity of being a very reliable source of information on the circulation of West Nile virus in an area. Unlike wild birds, they do not have high rates of viremia but by simple serobiological methods, it can be tested whether and to what extent they have been in contact with West Nile virus in the recent past.
For this reason, from 2010 onwards, Ecodevelopment proceeded to set up a surveillance network of WNV circulation (alongside the detection of WNV in pools of Culex pipiens mosquitoes involved in the transmission of the virus), initially using pigeons in collaboration with pigeon owners and then using domestic chicken (younger than 6 month old) in collaboration with poultry owners. Since then, this network has been extended to 180 settlements in 4 regions of the country (Central Macedonia, Thessaly, Western Greece and Crete), and Ecodevelopment carries out regular blood sampling (2-3 per year) on about 900 domestic chicken.
This year, for the first time, in order to stabilize the network and ensure 40-day-old chicks, Ecodevelopment took the initiative to supply chicks to previous or new partners-owners of hens in 30 settlements of five regional units of Central Macedonia by the end of March. The willingness of these owners to participate in this new initiative of Ecodevelopment relied on the relationship of trust that has been built up over the past years.
This action evolves in parallel with the large-scale physical presence of Ecodevelopment in high-risk settlements in relation to WNV, where, in addition to the classical larviciding, door-to-door control actions are carried out (in over 30,000 houses in 100 high-risk settlements in the Region of Central Macedonia every year). Provided the results are satisfactory, next year’s aim is to strengthen the surveillance network for West Nile virus by supplying sentinel chickens to more settlements (100) and beyond the Region of Central Macedonia.
