Epidemiology
West Nile fever is an arbovirosis caused by a Flavivirus. It is transmitted by the bites of female mosquitoes of the genus Culex (most often).
They usually bite at night. Cases of West Nile Fever in humans have been reported in Africa, the Middle East, India and Europe. The virus was detected in the New World in 1999, and has spread throughout North America and into Central America.
In 2003 in the United States, 9,000 cases of West Nile Fever and 264 deaths were recorded. This is the largest epidemic of West Nile Fever ever recorded.
Symptoms
In humans, the disease is without symptoms in 80% of cases.
After 3 to 6 days of incubation, there is a sudden appearance of high fever along with headaches and back pain, muscle pain, cough, swelling of lymph nodes in the neck, and often nausea, diarrhoea, respiratory symptoms and skin rash.
In 15% of cases, complications arise: meningitis, encephalitis, and more rarely hepatitis, pancreatitis or myocarditis.
Treatment
Treatment is symptomatic for the flulike syndromes.
Prevention
1. Vaccination
There is no vaccine.
2. Prevention of mosquito bites
Prevention is mainly based on :
- wearing ample clothing that covers the body,
- use of appropriate repellent products for the body and insecticide for clothing (Moustifluid High Protection Tropical Zones and Moustifluid Lotion For Fabrics and Clothing Tropical Zones) and repellent-sprayed mosquito nets (Moustifluid Lotion For Fabrics and Clothing Tropical Zones).