They launch an alert for a possible resurgence of the deadly Nile Virus and for which there is no treatment or vaccines.
Most Nile virus infections in humans are asymptomatic, only between 20% and 40% develop clinical infection, and this is associated with flu-like symptoms, according to the Carlos III National Institute of Health .
Infection to humans is usually the result of mosquito bites, which in turn become infected when they bite birds, the reservoir or host of the virus. But in addition to infecting humans, it can also infect other mammals, especially horses.
The first case of Nile virus was detected in 1937 in a woman from the West Nile district of Uganda, hence its name. Infected migratory birds, population movements and even climate change favor this virus and the mosquito that transmits it to settle on other continents, such as Europe.
In Spain, the circulation of the West Nile virus has been known for two decades and surveillance has been carried out in animals since 2001 and in humans since 2007. Until 2019, only 6 sporadic cases had been detected in humans.
The 77 positives in 2020 were the first outbreak with the highest number of cases. A report from the Center for the Coordination of Health Alerts and Emergencies (CCAES) of the Ministry of Health, stated: “The increase in the incidence of cases in animals and humans in the areas of circulation of the virus since August (2020) with a high percentage of serious cases constitutes an unexpected change, given the previous epidemiological characteristics ”.