Greece records 157 West Nile virus cases as European infections climb

Infection surge across Greek regions

National health surveillance in Greece registered 157 domestic West Nile virus infections through 19 August 2026, according to data from the National Public Health Organization (EODY). The weekly bulletin confirmed 47 new cases and 4 deaths over seven days, bringing total fatalities to 13, all among patients older than 65 years. Later reports on 22 August cited 15 deaths. At the time of the bulletin, 42 patients remained hospitalized across the country, with 23 receiving treatment in intensive care units. Case numbers exceed those from the same period in 2025, when authorities recorded 96 infections and 9 deaths. Infections have appeared across five administrative regions: Attica, Thessaly, Central Macedonia, Peloponnese, and Central Greece.

EODY President Theodoros Vasilakopoulos described the current trajectory during an interview with Skai:

We have an outbreak of West Nile virus that reminds us of 2018. Every year we have different numbers of patients and the reason is that although there is a national mosquito control program, which is drawn up every year based on the epidemiological data of the previous year and is executed normally, we cannot fully predict the climatic conditions that will prevail in spring, when large mosquito populations develop.

European transmission and seasonal factors

Data published by the European Centre for Disease Prevention and Control (ECDC) on 21 August 2026 positioned Greece as the second most affected country in Europe. Italy recorded the highest transmission with 311 locally acquired cases across 46 distinct regions, compared to 157 cases across 17 regions in Greece. Spain reported 63 infections, North Macedonia 37, Romania 28, France 17, and Serbia 6. Low single-case counts appeared in Albania, Austria, Germany, and Kosovo, alongside 2 cases in the Netherlands. Epidemiologists link the broader seasonal distribution to higher temperatures, spring rainfall patterns, and the joint presence of wild bird reservoirs and mosquito vectors.

Regional focus in Attica and municipal measures

Eastern Attica and the northern suburbs of Athens account for 66% of all Greek infections, placing 20 local municipal administrations on elevated monitoring protocols. The municipality of Spata-Artemida recorded the highest localized toll with 14 confirmed cases, followed by Markopoulo Mesogaias with 11 and Vari-Voula-Vouliagmeni with 9. Additional clusters emerged in Agia Paraskevi (6 cases), Pallini (5 cases), Chalandri (5 cases), and Glyfada (4 cases). Municipal teams in Agia Paraskevi conducted widespread spraying through thousands of drainage shafts, while Kifisia deployed biological larvicides in standing water reservoirs. In the northern border municipality of Soufli, authorities tested specialized thermal traps designed to capture female mosquitoes using artificial scent and heat emissions.

Clinical management and spraying constraints

Approximately 80% of infected individuals remain asymptomatic, while 20% experience mild illness including fever, headache, muscle pain, and physical fatigue. Less than 1% of cases develop severe central nervous system complications such as encephalitis, meningitis, disorientation, and acute paralysis. The virus transmits exclusively through bites from infected mosquitoes, without direct person-to-person spread. No vaccine or specific antiviral therapy exists for human use, leaving medical teams to rely on supportive symptomatic care. Operational spraying plans expanded 30% beyond initial targets in Attica, though environmental and toxicity regulations prevent further pesticide increases.

Vasilakopoulos noted the operational ceiling during an appearance on ERTnews:

We must be within scientifically predefined limits in how aggressive we become.