West Nile virus spreads across Europe: Greece records surge in severe cases, while Italy remains the main infection hotspot

Europe is facing a new seasonal surge in West Nile virus infections. The situation is currently most serious in Greece and Italy, where the number of cases is rising rapidly and doctors are warning of severe complications among elderly patients. At the same time, Germany has confirmed its first case of the season, indicating that the virus’s range continues to expand.

According to Greece’s National Public Health Organization, 23 new cases were registered in the past week alone. Since the start of the transmission season, which began in spring, 65 cases have been identified in the country. Of these, 54 people developed a severe neuroinvasive form of the infection, including encephalitis, meningitis or acute paralysis. In 11 other patients, the disease was mild or did not affect the central nervous system. So far, six deaths have been confirmed; all those who died were over 65 and suffered severe complications.

The most serious situation in Europe remains in Italy. The country has been considered one of the main areas of virus circulation for several years, while warm and humid summer weather creates ideal conditions for mosquitoes to reproduce — the main carriers of the infection. This season, Italy is leading Europe in the number of registered cases.

Experts are particularly concerned about the first confirmed case of West Nile virus in Germany this season. Although the disease remains isolated there for now, doctors view it as further evidence that, due to climate change, disease-carrying mosquitoes are gradually spreading farther north.

West Nile virus is transmitted to humans exclusively through the bites of infected mosquitoes, which become infected after feeding on wild birds. The infection is virtually not transmitted from person to person, except in extremely rare cases involving blood transfusions, organ transplants or transmission from mother to child.

According to estimates by the World Health Organization, around 80% of those infected experience no symptoms at all. Approximately one in five develops fever, headache, weakness, muscle and joint pain, and sometimes a skin rash. However, fewer than 1% of those infected develop severe nervous system disease, such as encephalitis or meningitis. These forms of the disease are the most likely to lead to hospitalization and death, especially among elderly people and patients with weakened immune systems.

Experts attribute the rise in cases to an abnormally hot summer in Europe. High temperatures and a longer warm season allow mosquitoes to reproduce more quickly and remain active for longer, significantly increasing the risk of infection spreading. In response, the European Centre for Disease Prevention and Control is urging countries to strengthen monitoring, treat areas for mosquitoes and inform the public about protective measures.

Experts recommend using insect repellent, wearing clothing that covers the body in the evening and at night, installing mosquito screens and avoiding leaving containers of standing water near homes, where mosquitoes can breed. As there is currently no specific treatment or widely used human vaccine, preventing mosquito bites remains the main form of protection.