3 cases detected in PACA

2023-08-21 09:22:00

Lately, we have heard a lot about the tiger mosquito. Vector of many viruses like denguechikungunya or even medicineits spread caused much concern and continues to be monitored in France.

But it is not the only mosquito to transmit diseases. The culex, a common mosquito widespread in France, can transmit West Nile virus. The latter has just been detected in France. In a report published on August 18, 2023, the Regional Health Agency (ARS) Provence-Alpes-Côte d’Azur (Paca) announces the detection of three cases of infection.

Nile virus: a frequency of infections for 15 years

Also known as the West-Nile virus, West Nile virus is an arbovirus transmitted to humans by culex mosquitoes. This common mosquito in France mainly bites at night. “Unlike other arboviruses (dengue, chikungunya or zika in particular, whose vector is the tiger mosquito), humans and horses are considered to be “accidental hosts” of the virus. no human-to-human transmission, nor transmission of the virus from human to human via the mosquito“, details the Regional Health Agency (ARS) Provence-Alpes-Côte d’Azur (Paca). Thus, this limits the risks of epidemics. However, the virus has been spreading widely since its appearance in East Africa. Cases have been reported in Europe since 1960. “For about fifteen years the frequency of infections has accelerated“, details the Pasteur Institute.

Today the virus is endemic in several European countries. “In 2018, Europe had to face a strong epidemic with a number of cases much higher than the sum of the previous 10 years“, details the organization. In France, 7 cases were diagnosed in the Var in 2003. This year, 3 new cases have just been detected in the PACA region. “A person in Antibes in the Alpes-Maritimes, a person in Gardanne in the Bouches-du-Rhône and a person in Toulon in the Var”, details the ARS. But what is it exactly?

What is West Nile virus?

In the majority of cases, he is asymptomatic. However, there may be symptomatic forms which result in the appearance of a sudden fever, 3 to 6 days after virus incubation. Other symptoms may then appear:

Headaches and backaches ,
Muscle pain;
A cough ;
Swollen neck glands ;
A skin rash;
Nausea ;
Abdominal pain ;
Diarrhea;
And respiratory symptoms.

Nile virus: risk of serious complications

In the most serious cases, the virus can cause neurological damage such as meningitis or encephalitis. However, they occur in less than 1% of cases. “Even more rarely, other complications (hepatitis, pancreatitis or myocarditis) may occur“, adds the Pasteur Institute. If in most cases, the patient recovers alone, the virus can be fatal in older adults.

To avoid any risk of spreading the virus, a triple surveillance system in humans, birds and horses has been set up in France. The PACA region has particularly strengthened its monitoring system. At the same time, the ARS recommends preventing contamination by: