Several countries around the Mediterranean have previously reported resistance to insecticides in domestic mosquitoes. So the ITM embarked on a study in its own insects (a kind of zoo for mosquitoes, ed.). The researchers applied what is called the World Health Organization (WHO) susceptibility test: exposed mosquitoes to a predetermined amount of insecticide, and then looked at the percentage of mosquitoes that were still alive after 24 hours. Pesticides Permethrin, Deltamethrin, Malathion, Bendiocarb and DDT have been tested. Most of these active substances can be found in the various mosquito sprays and other insecticides available at the store.
If less than 90% of mosquitoes die in such a test, then we can talk about resistance. According to ITM, it turns out that this is indeed the case. The researchers say that now proven resistance poses a problem in the event of potential outbreaks of viruses that can be transmitted by household mosquitoes. It appears that “in such outbreaks, such as West Nile virus, the standard response is to contain the spread by spraying insecticides.” “Because of the resistance, such a pesticide is no longer an option and we are more vulnerable in the event of an outbreak.”
What is West Nile fever?
West Nile fever is an increasingly common disease in Europe that mainly affects birds and horses, but sometimes also humans. Then a small percentage of those infected develop flu-like symptoms, and exceptionally the disease is also fatal.
ITM is already looking for alternatives. These are needed in biological control and artificial intelligence, among others.
