Geographic distribution and future expansion of Aedes albopictus in the Democratic Republic of the Congo

Abstract

Aedes albopictus with an Asian origin has been reported from central African countries. The establishment of this mosquito species poses a serious threat as the vector of various infectious diseases. Since information about Ae. albopictus in Democratic Republic of the Congo (DRC) is scarce, we investigated the current distribution of this mosquito species. Based on the factors affecting the distribution, we predicted future distribution. We conduced entomological surveys in Kinshasa and three neighboring cities from May 2017 to September 2019. The survey was extended to seven inland cities. A total of 19 environmental variables were examined using the maximum entropy method to identify areas suitable for Ae. albopictus to establish a population. We found Ae. albopictus at 21 of 23 sites in Kinshasa and three neighboring cities. For the first time Ae. albopictus was also found from three of seven inland cities, while it was not found in four cities located in the eastern and southeastern parts of DRC. A maximum entropy model revealed that the occurrence of Ae. albopictus was positively associated with maximum temperature of the warmest month, and negatively associated with wider mean diurnal temperature range and enhanced vegetation index. The model predicted that most parts of DRC are suitable for the establishment of the mosquito. The unsuitable areas were the eastern and southeastern highlands, which have low temperatures and long dry seasons. We confirmed that Ae. albopictus is well established in Kinshasa and its neighboring cities. The expansion of Ae. albopictus to the inland is ongoing, and in the future the mosquito may establish in most parts of DRC.