Disinsection
Spraying aircraft for insects, a procedure called disinsection.
Some countries in Africa, Latin America, the Caribbean, Australia and the South Pacific require the spraying of the aircraft passenger compartment with insecticide while passengers are present.
This is done to prevent the importation of insects such as mosquitos.
Disinsection procedures have been determined to be safe by the World Health Organization (WHO).
However, they may aggravate allergies.