The first case of West Nile virus occurred in Larissa, as announced by EODY.

The patient presented a picture of mild encephalitis, had onset of symptoms within the last ten days of June 2024 and has been discharged from the hospital.

Outbreaks of West Nile virus infection occur in many countries worldwide, as well as in many European countries, on an annual basis, usually during the summer and autumn months. From 2010 onwards, cases appear almost every year in our country and – therefore – the recurrence of cases is expected in every period of transmission. In May 2024, the EODY informed health professionals nationwide about the need to be alert for the disease and issued a relevant Press Release to inform the public, with recommendations for preventive measures against mosquitoes.

As noted by EODY, due to mild winter temperatures, a relatively early onset of the human transmission period was recorded, with the first case occurring during the last ten days of June. Therefore, the EODY warns that there may be an intense circulation of the virus during the current period and recommends taking precautionary measures against mosquitoes.

As the epidemiology of the virus is determined by many factors, outbreak areas cannot be predicted with certainty. Therefore, the EODY recommends the observance of individual protection measures against mosquitoes throughout the territory, throughout the period of circulation of mosquitoes:

  • Use approved body and room repellents (according to instructions for use), screens, mosquito nets, air conditioners/fans, suitable (long) clothing.
  • Do not leave stagnant water anywhere (thus effectively helping to limit mosquito breeding grounds in private areas).

Older people and people with chronic underlying diseases should take their measures with particular consistency.

West Nile virus is transmitted primarily by the bite of infected “common” mosquitoes, which are infected by infected (mainly wild) birds. Infected people do not further transmit the virus to other mosquitoes or to other people (by direct contact).

Most people who become infected do not get sick at all or have only mild symptoms, while a small percentage (less than 1% of those who become infected) develop severe disease that affects the nervous system (mainly encephalitis or meningitis). Older people (over 50 years old), as well as people with immunosuppression and chronic underlying diseases, are more at risk of becoming seriously ill.

In each period of transmission, with the aim of timely implementation of targeted response and prevention measures, the EODY carries out enhanced epidemiological surveillance of the disease and actions to inform health professionals and the public and is in constant communication and cooperation with the competent national and local authorities. A special cross-sectoral Working Group of the Ministry of Health is immediately conducting a risk assessment and defining the affected and high-risk areas. The recommended prevention and response actions are detailed, for each “Risk Level”, in the Ministry of Health’s comprehensive “West Nile Virus Infection Action Plan”.