Greek authorities say 45 new locally transmitted West Nile virus infections were reported last week, with Attica taking the hardest hit as the summer of 2026 turns into another test of how quickly public health systems can be stretched thin. The National Public Health Organization of Greece, EODY, says the epidemiological picture has deteriorated significantly, and its weekly surveillance report, with data up to 12 August 2026, records 110 domestically acquired cases across the country.
Attica Takes the Hit
The numbers are blunt. Of the 110 laboratory-confirmed domestically acquired cases, 81 involved central nervous system manifestations such as encephalitis, meningitis, meningoencephalitis or acute flaccid paralysis. Another 29 cases were milder or showed no central nervous system involvement. By 12 August, nine deaths had been recorded among patients with West Nile virus infection and central nervous system manifestations. All of them were over 65 years old, with a median age of 82 and an age range from 66 to 91.
Thirty-five patients were still in hospital. Nineteen were in ordinary wards and 16 were in Intensive Care Units. None were in a High Dependency Unit. Sixty-one patients had been discharged, while five recorded cases did not need hospitalisation. The median age of patients with central nervous system manifestations is 73, though cases range from 19 to 91. The report also notes that the 110 confirmed cases do not necessarily reflect the total number infected. EODY cites a 2010 seroepidemiological study suggesting that for every single case with central nervous system involvement there are around 140 infected people who either develop mild symptoms or remain asymptomatic.
The virus has not stayed neatly within one administrative box. Cases had been recorded and investigated in 39 municipalities, in 14 regional units and in four regions: Attica, Thessaly, Central Macedonia and the Peloponnese. In Attica, areas in East Attica and the North, West, Central and South Sectors of Athens, as well as Piraeus, have been affected. Outside Attica, cases were recorded in Karditsa, Larissa, Trikala, Imathia, Thessaloniki, Pella, Serres and Laconia.
East Attica appears particularly hard-hit. In Spata-Artemida, 11 patients with central nervous system manifestations and two without such manifestations have been recorded. In Markopoulo Mesogaias, eight patients with central nervous system involvement and three without have been reported. Vari-Voula-Vouliagmeni has five cases with central nervous system manifestations and two without. Pallini has five cases with central nervous system involvement, Agia Paraskevi six, Acharnes three, Chalandri three, Glyfada three and the municipality of Athens three.
The Public Health Machine
EODY says every reported case is investigated within 24 hours, with daily communication with laboratories and support for suspected cases. In May 2026, an information letter was sent to all health facilities and medical associations in the country. In March 2026, the Ministry of Health issued a specific circular on integrated mosquito management programmes. EODY has asked regions and municipalities for the timely launch, proper organisation and effective implementation of mosquito-control programmes. It also installs mosquito traps in different parts of Greece, and for 2026 an enhanced entomological surveillance network has been set up.
That’s the official machinery: reports, circulars, letters, traps, networks. Necessary, yes. But the virus has already spread through 39 municipalities, and the report says additional cases are likely in the coming weeks, both in areas where the virus is already circulating and potentially in new areas. The state can count, classify and circulate memos. The mosquitoes don’t care.
A Virus That Stays
EODY says cases have been recorded in Greece during the periods from 2010 to 2014 and from 2017 to 2025, mainly in the summer and autumn months. The almost annual occurrence of cases since 2010 indicates, according to the report, that West Nile virus has become established in Greece, as it has in other European countries. That’s the quiet admission buried in the surveillance language: this is no one-off emergency, but a recurring condition managed through public warnings and hospital beds while the underlying exposure remains.
Veterinary surveillance also showed recent West Nile virus infections in equines at five sites or settlements in East Attica, Drama and Preveza, as well as in the Metropolitan Unit of Thessaloniki. The same geography keeps reappearing. The same summer pattern keeps returning. The same institutions keep issuing updates while the numbers climb.
By 12 August, EODY had classified additional municipalities as high-risk areas on the basis of epidemiological and geomorphological data: Kifisia, Iraklio, Filothei-Psychiko and Metamorfosi in the North Sector of Athens, Kallithea and Nea Smyrni in the South Sector, Nea Filadelfeia-Nea Chalkidona and Dafni-Ymittos in the Central Sector, plus Amfipoli in Serres, Heroic City of Naousa in Imathia and Delta in the Metropolitan Unit of Thessaloniki. No human cases had been recorded there at the time of the report. The map keeps expanding before the first patient arrives.
The public health response is real. So is the scale of the outbreak. And so is the fact that, in Greece as elsewhere, the burden lands on ordinary people, older patients, hospital wards and intensive care units while the official apparatus tries to stay one step ahead of a virus that has already settled in.