Malaria Transmission Associated with Airplane Travel

Plasmodium falciparum malaria was diagnosed in 3 patients in Sã o Paulo during a 5 day period between August 31, and September 4, 1996, at a time and place where malaria transmission does not occur. After investigation of the 3 cases it was determined that the infections were acquired as a result of an international airplane flight from Lebanon to São Paulo on August 16, which included a 30 minute stop-over in Abidjan, Ivory Coast, Africa. During the epidemiological evaluation, it was found that each of the 3 patients had been seated in the first class cabin. Entomological investigation at the airport revealed the presence of 4 specimens of Anopheles gambiae in airplanes (3 in the first class cabin and 1 in the luggage compartment) used on this route. The species of mosquito identified is predominant in Africa. Two of the patients were seriously ill, but all recovered after treatment with either mefloquine (1 patient) or artesunate (2 patients). A survey of other passengers on the same flight or on similar Aights did not reveal any other eases of malaria. Malaria was not considered during initial evaluation by the attending physicians at the three different hospitals where the patients were admitted. These cases reveal the existence of vector borne disease transmission during airplane travel, and emphasize the importance of obtaining a travel history during the evaluation of an ill patient. In addition, the cases reinforce the need for vigilance in the control of vectors of disease around seaports, airports and hospitals.