Mosquito capture in Kampenhout reassuring: no mosquitoes infected with malaria were found

A couple in Kampenhout were infected with and died of malaria at the end of September. Following these deaths, researchers from the Institute of Tropical Medicine (ITM) conducted a field study in the surrounding area to identify the mosquito species living nearby. The results of their investigation are now available and contain no surprises. The researchers did not find any exotic malaria mosquitoes nor any indigenous mosquitoes that carry malaria. This supports their hypothesis that the couple was infected by a malaria-carrying mosquito that arrived in Belgium via an airport.

The ITM researchers carried out an in-depth search for mosquitoes and their larvae in their common breeding sites such as tree holes, marshes, sewers, ponds, and rainwater tanks. In addition to the couple’s house and garden, they also explored some 139 other breeding sites in a buffer zone of 500 meter which included 23 gardens, pools in the “Torfbroek” nature reserve, tree holes and the Hellebos pond.

The objective was to find the Anopheles mosquito, the only type able to transmit malaria. This group consists of several species including the tropical ‘falciparum’ species which killed the couple in Kampenhout. This deadly form of malaria is transmitted only by certain species of mosquitoes of the Anopheles genus, but this type of mosquito was not detected during the field investigation.

However, two Anopheles mosquitoes indigenous to Belgium were found, one adult and one larva. This comes as no surprise as these species are also found in other places in Belgium and in breeding sites such as ponds and marshes. They are believed to be incapable of transmitting the tropical falciparum malaria. To ascertain that the malaria parasite was not present, the scientists tested the adult specimen. The result was negative.

Wim Van Bortel of ITM: “We didn’t find exotic mosquitoes and we didn’t find any traces of local malaria transmission through indigenous mosquitoes. These results are reassuring and support our hypothesis that the couple from Kampenhout died after being infected by a single mosquito that arrived in Belgium via an airport. We can assume that the risk of local transmission of malaria is extremely low. But we must remain vigilant and constantly monitor the arrival of exotic mosquito species in Belgium."