Many countries require disinsection of aircraft (to kill insects) arriving from countries where diseases that are spread by insects, such as malaria and yellow fever, occur. There have been a number of cases of malaria affecting individuals who live or work in the vicinity of airports in countries where malaria is not present, thought to be due to the escape of malaria-carrying mosquitoes transported on aircraft. Some countries, e.g. Australia and New Zealand, routinely carry out disinsection to prevent the inadvertent introduction of species that may harm their agriculture.
Disinsection is a public health measure that is mandated by the International Health Regulations (Annex 2). It involves treatment of the interior of the aircraft with insecticides specified by WHO. The different procedures currently in use are as follows:
- treatment of the interior of the aircraft using a quick-acting insecticide spray immediately before take-off, with the passengers on board;
- treatment of the interior of the aircraft on the ground before passengers come on board, using a residual-insecticide aerosol, plus additional in-flight treatment with a quick-acting spray shortly before landing;
- regular application of a residual insecticide to all internal surfaces of the aircraft, except those in food preparation areas.
Passengers are sometimes concerned about their exposure to insecticide sprays during air travel, and some have reported feeling unwell after spraying of aircraft for disinsection. However, WHO has found no evidence that the specified insecticide sprays are harmful to human health when used as recommended.