Mosquito bites and health concerns

After recent exposure to mosquitoes, a sudden fever should prompt a medical consultation. Certain neurological symptoms require immediate contact with emergency services. In Île-de-France, where the West Nile virus is under enhanced surveillance, the correct response is not to panic at every bump, but to identify the key associations: recent exposure to mosquitoes, sudden fever and especially neurological symptoms.

Recent case numbers in Île-de-France

According to the regional bulletin from Santé publique France published on October 22, 2026, 27 autochthonous human cases had been recorded in Île-de-France as of October 19, including 15 neuroinvasive forms. Four neuroinvasive forms were followed by the deaths of the patients. These figures describe the cases identified by surveillance: they do not necessarily reflect all infections, as many can go unnoticed.

Transmission of the West Nile virus

The West Nile virus, or West Nile virus, is mainly transmitted by mosquitoes of the genus Culex. These mosquitoes become infected by biting birds carrying the virus, and can then bite humans. In everyday life, an infected person does not directly transmit the disease to their surroundings.

Symptoms and medical advice

Most people infected do not show any symptoms. When symptoms do appear, they can resemble a common viral syndrome: sudden fever, headaches, muscle pain, fatigue, sometimes a skin rash. On their own, these symptoms are not sufficient to conclude an infection by the West Nile virus. However, they should prompt a medical consultation when they occur.