Towards the invasion of wild and rural forested areas in Gabon (Central Africa) by the Asian tiger mosquito Aedes albopictus : potential risks from the one health perspective

2023

Article référencé dans le Web of Science WOS:001050818100002

Obame-Nkoghe J., Roiz David, Ngangue M. F., Costantini Carlo, Rahola Nil, Jiolle D., Lehmann D., Makaga L., Ayala Diego, Kengne Pierre, Paupy Christophe

PLoS Neglected Tropical Diseases, 2023, 17 (8), p. e0011501 [22 p.] ISSN 1935-2735

Background Since its first record in urban areas of Central-Africa in the 2000s, the invasive mosquito, Aedes albopictus, has spread throughout the region, including in remote villages in forested areas, causing outbreaks of Aedes-borne diseases, such as dengue and chikungunya. Such invasion might enhance Ae. albopictus interactions with wild animals in forest ecosystems and favor the spillover of zoonotic arboviruses to humans.The aim of this study was to monitor Ae. albopictus spread in the wildlife reserve of La Lope National Park (Gabon), and evaluate the magnitude of the rainforest ecosystem colonization. MethodologyFrom 2014 to 2018, we used ovitraps, larval surveys, BG-Sentinel traps, and human landing catches along an anthropization gradient from La Lope village to the natural forest in the Park. ConclusionsWe detected Ae. albopictus in gallery forest up to 15 km away from La Lope village. However, Ae. albopictus was significantly more abundant at anthropogenic sites than in less anthropized areas. The number of eggs laid by Ae. albopictus decreased progressively with the distance from the forest fringe up to 200m inside the forest. Our results suggested that in forest ecosystems, high Ae. albopictus density is mainly observed at interfaces between anthropized and natural forested environments. Additionally, our data suggested that Ae. albopictus may act as a bridge vector of zoonotic pathogens between wild and anthropogenic compartments. Author summarySince its first record in urban areas of Central Africa in the 2000s, the anthropophilic and invasive mosquito, Aedes albopictus, has continued to spread across remote rural areas and has promoted outbreaks of Aedes-borne diseases, such as dengue, chikungunya and Zika. Such invasion might enhance Ae. albopictus interactions with wild animals in forests neighboring villages and favor the spillover of zoonotic arboviruses to humans.In this study, we reported the sustained spread of the Ae. albopictus in the wildlife reserve of La Lope National Park (LNP, Gabon), and we evaluated the magnitude of its colonization of this rainforest ecosystem. Using various sampling methods between 2014 and 2018, we detected Ae. albopictus presence in wild forest galleries up to 15 km away from La Lope, the main inhabited village within the park limits. We demonstrated that Ae. albopictus can invade forest ecosystems where the human presence is low or absent. These data indicate that Ae. albopictus may interact with wild animals and act as a bridge vector of zoonotic pathogens between the wild and anthropogenic compartments. However, our results showed that Ae. albopictus population density is higher at interfaces between the village and the forest. This suggests that this species might be present at the interface between anthropized and wild environments where the probability of contact with wild animals is increased, and consequently the likelihood of contributing to sylvatic and bridge transmission of pathogens. Our results also suggested that the presence of humans facilitates the colonization of natural forested habitat by this invasive species.

Entomologie médicale / Parasitologie / Virologie [052]

GABON

Fonds IRD [F B010090152]

fdi:010090152