WEST NILE VIRUS

The West Nile virus belongs to the Flaviviridae family. The virus reservoirs are wild birds and mosquitoes (most frequently type Culex), whose bites are the main means of transmission to humans.

The incubation period from the time of the bite of the infected mosquito varies between 2 and 14 days, but may also be 21 days in those with immune deficiency.

West Nile infections are asymptomatic in 80% of people but may cause fever, headache and nausea; in some cases meningitis and/or encephalitis may occur, which can cause serious brain damage or death. There is no specific therapy for West Nile fever. In most cases, symptoms go away on their own after a few days or may last for a few weeks. In the most severe cases, hospitalization is required, where treatments given include intravenous fluids and assisted breathing.

Diagnosis is mainly performed by serological testing for the determination of WNV-specific IgG and IgM antibodies. Alternatively, it may also be performed by PCR or viral culture on serum and cerebrospinal fluid specimens.