West Nile virus: spread rises again in Greece as authorities stay on alert

The West Nile virus is circulating more widely in Greece, prompting health and local authorities to step up efforts to curb its spread. Particular emphasis is being placed on mosquito control, with targeted spraying in areas where their populations are densest.

In the space of a week, 47 additional cases were confirmed, bringing the total number of infections to 157. Cases have been detected in 45 municipalities across five regions of the country: Attica, Thessaly, Central Macedonia, the Peloponnese and Central Greece.

Over the same period, four more deaths were recorded, raising the total death toll to 13, with the median age of those who died being 82. At the same time, 42 patients are in hospital, 23 of them in intensive care units.

Of the 157 confirmed cases, 116 developed symptoms affecting the central nervous system, including severe headache, lethargy and high fever.

Scientists stress, however, that the official figures do not capture the full number of infections in the population. This is because most people who contract the virus either show no symptoms at all or develop only mild illness and therefore are not diagnosed. According to estimates by the National Public Health Organisation (EODY), for every confirmed case, there may be roughly 140 infections that go undetected.

Eastern Attica is particularly hard hit. In the municipality of Spata-Artemida, 16 cases have been identified, 14 of which involve the central nervous system. In the municipality of Markopoulo Mesogaias, 13 cases have been recorded, 11 of which presented similar manifestations. Meanwhile, in the municipality of Larissa, the number of confirmed cases stands at 11.

As part of efforts to reduce mosquito populations, the regions are continuing targeted control operations. In Eastern Attica, these activities have been significantly stepped up and, in some cases, are carried out daily, including door-to-door interventions. Teams focus mainly on spots where stagnant water can accumulate, such as drains, as well as places like cemeteries, which can create ideal conditions for mosquitoes to breed.

At the same time, experts highlight the importance of personal protection. They recommend the regular use of insect repellents and the removal of small pockets of stagnant water from yards and balconies, such as those that form in flowerpots, saucers, buckets, and other containers. Where possible, they also advise wearing clothing that covers most of the body, especially in the evening and particularly in areas where increased transmission of the virus has been recorded.

The role of infected birds in transmission

As hygiene and epidemiology professor Gkikas Magiorkinis told the public broadcaster ERT, infected birds such as crows, magpies, and jays play a key role in the virus's transmission cycle. Mosquitoes can become infected when they feed on birds carrying the virus and can then pass it on.

Regarding the occurrence of cases in parts of Attica, the professor notes that this may also be linked to changes observed in recent years. Among the possible factors under consideration are the effects of Storm Daniel, which hit Thessaly in 2023, a region where intense circulation of the virus had previously been recorded.