West Nile Virus: 3 people infected in Var, what is this virus transmitted by mosquitoes?

In a press release Published on August 12, 2024, the Provence-Alpes-Côte d’Azur Regional Health Agency (ARS) reported the identification of 3 cas d’infection au West Nile virus (or West Nile virus) in the Var department, in Ollioules, Six-Fours-les-Plages and La Seyne-sur-Mer. The health authority also reported a case in a horse from Six-Fours-les-Plages, during the same period.

This is a bird virus that can also “accidentally” infect humans and horses, recalls Public Health France. This transmission is called accidental because it occurs through “mosquitoes (mainly of the Culex genus) which are contaminated exclusively through contact with infected birds”, explains the ARS Provence-Alpes-Côte d’Azur. It adds that the “Culex mosquito is the common mosquito in metropolitan France” and thatit stings mainly in the evening and at night. Public Health France adds that the virus can also be transmitted, in extremely rare cases, by products of human origin, such as blood transfusions or organ, tissue or cell transplants.

West Nile Virus: How to recognize it and what are the symptoms?

After infection with West Nile virus, the incubation period is two to six days, but can extend to fourteen days. According to health authorities, “In 80% of cases, human West Nile virus infection is said to be ‘asymptomatic’that is, the patient has no symptoms“.

However, in 20% of cases, the disease may present with a syndrome influenza-like. These include fever, body aches or even headaches. In rare cases (1 in 150), it may present neurological complications in people who are already weakenedHealth authorities are calling on people with these symptoms to consult a doctor.

What are the best reflexes to have to limit the risks of being infected by the West Nile virus?

West Nile virus is a notifiable disease since 2021recalls the Ministry of Labor, Health and Solidarity. In addition, when a case is identified, the health authorities investigate the places of contamination and identify other potential cases. Indeed, the ARS Provence-Alpes-Côte d’Azur states that “The Mediterranean Interdepartmental Mosquito Control Agreement is conducting investigations in the affected areas in order to identify possible locations where Culex mosquitoes are proliferating.”, and that she herself has “strengthened the surveillance system for West Nile virus infections by raising awareness among establishments and health professionals in the sector about the identification and screening of any suspected cases”.

The ARS Provence-Alpes-Côte d’Azur also recalled the right reflexes to adopt pour limit the risks of being contaminated by the West Nile virus. Indeed, as health authorities specify, “Better prevention against disease lies in protection against mosquito bites“ as well as in the fight against places that can promote the proliferation of mosquitoes around homes. Health authorities recommend in particular:

• protect yourself from mosquitoes with covering clothing and a mosquito repellent,
• protect your home with mosquito netting,
• install mosquito nets above the bed or a crib for newborns,
• use fans to annoy mosquitoes,
• avoid stagnant water around the home,
• avoid fly-tipping.

In the event of the appearance of suggestive symptoms such as a sudden fever accompanied by headaches, muscle pain, a rash, or even behavioral problems or incoherent speech, the Provence-Alpes-Côte d’Azur Regional Health Agency recommends: consult your doctor immediately.

Sources :

• Indigenous cases of West Nile virus infection in Var – Provence-Alpes-Côte d’Azur Regional Health Agency – August 12, 2024
• West Nile Virus – Public Health France
• West Nile fever or West Nile virus infection – Ministry of Labor, Health and Solidarity