The National Public Health Organization (ERD) informs that the first cases of western Nile virus for the 2025 transmission period were diagnosed in our country.

Specifically, during the last 48 hours – four cases of the infection in the Attica region were diagnosed, with most likely exhibition sites being the Regional Units of West Attica, Piraeus and Islands (in the municipalities of Aspropyrgos, Korydallos and Salamis). The incidents relate to patients over 65 years of age who presented an image of encephalitis / meningoencephalitis and had symptoms in the last ten days of June 2025.

West Nile virus infection occur in many countries worldwide, as in many European countries, on an annual basis, usually during the summer and autumn months. From 2010 onwards, there have been cases of almost every year in our country, with the result that the recurrence of incidents are considered to be expected in each transmission period. Given the expected circulation of the virus and during the current period, EDYY informed health professionals nationwide in May 2025 about their need for alert to the disease and in early June 2025 issued a press release to inform the public, with recommendations for the taking of measures.

As the epidemiology of the virus is determined by many factors, the incidence areas cannot be safely predicted. That is why EDYS recommends that diligently taking on individual mosquitoes throughout the territory, throughout the mosquito circulation and calls on citizens:

  • Use approved body and space insect repellents (according to the instructions for use), screens, mosquitoes, air conditioners/fans, suitable (long) clothes.
  • Do not leave stagnant waters nowhere (thus helping to reduce mosquito breeding outbreaks in private spaces).

Older people, people with immunosuppression and people with chronic underlying diseases, must adhere to individual mosquito protection measures with particular consistency, as they are more likely to get seriously ill.

EDY will publish updated reports every Wednesday with current epidemiological data (number of cases at the municipality level), from which citizens can be informed of the municipalities of the country where cases of the disease were recorded during the period 2025 (and therefore, which is certainly released).

The West Nile virus is mainly transmitted by the sting of infected “common” mosquitoes, which are contaminated by infected (mainly wild) birds. People who are infected do not further transmit the virus to other mosquitoes or other people (by direct contact). Most of them infected people do not get sick at all or only have mild symptoms, while in a small percentage (less than 1% of those infected) they develop severe disease that affects the nervous system (mainly encephalitis or meningitis).

During each transmission period, and with the aim of timely implementing targeted response and prevention measures, EDY carries out enhanced epidemiological surveillance of the disease and active entomological surveillance at national level, which has been significantly enhanced in recent years. At the same time, it informs health and public health professionals and the public, immediately investigates the incidents and is in constant communication and cooperation with the competent national authorities and local authorities, which institutionally execute mosquito control programs.