In order to prevent the spread of West Nile virus through contaminated blood or human body material, candidate donors from areas where autochthonous cases are found must wait before donating. From now until the end of November, the FAMHP will provide weekly updates on the affected areas. This weekly update is based on data from the European Centre for Disease Prevention and Control (ECDC).
West Nile virus (WNV) is a virus that circulates among migratory birds and is transmitted by mosquitoes. The virus can also be trasmitted to humans and a large variety of mammalians. In 80% of infected persons the disease is asymptomatic, i.e. without symptoms. In 20% of infected persons, there is a flu-like illness characterised by a sudden onset of fever (> 39°C), headache, myalgia (muscle pain) and gastrointestinal symptoms, which disappear within a week. In severe cases, the infection may lead to neurological symptoms such as meningoencephalitis, encephalitis, meningitis or poliomyelitis.
West Nile virus can be transmitted through blood products. There is also a risk of transmitting the virus via tissue and cell transplantation. To avoid this, candidate donors who have stayed in areas where autochthonous infections have been detected, must wait until 28 days after leaving the area, unless an individual nucleic acid amplification test (NAT) is negative.
An overview of affected areas will be updated weekly from now until the end of November 2022.