A literature review of dispersal pathways of Aedes albopictus across different spatial scales: implications for vector surveillance

Abstract

Background Aedes albopictus is a highly invasive species and an important vector of dengue and chikungunya viruses. Indigenous to Southeast Asia, Ae. albopictus has successfully invaded every inhabited continent, except Antarctica, in the past 80 years. Vector surveillance and control at points of entry (PoE) is the most critical front line of defence against the introduction of Ae. albopictus to new areas. Identifying the pathways by which Ae. albopictus are introduced is the key to implementing effective vector surveillance to rapidly detect introductions and to eliminate them. Methods A literature review was conducted to identify studies and data sources reporting the known and suspected dispersal pathways of human-mediated Ae. albopictus dispersal between 1940–2020. Studies and data sources reporting the first introduction of Ae. albopictus in a new country were selected for data extraction and analyses. Results Between 1940–2020, Ae. albopictus was reported via various dispersal pathways into 86 new countries. Two main dispersal pathways were identified: (1) at global and continental spatial scales, maritime sea transport was the main dispersal pathway for Ae. albopictus into new countries in the middle to late 20th Century, with ships carrying used tyres of particular importance during the 1980s and 1990s, and (2) at continental and national spatial scales, the passive transportation of Ae. albopictus in ground vehicles and to a lesser extent the trade of used tyres and maritime sea transport appear to be the major drivers of Ae. albopictus dispersal into new countries, especially in Europe. Finally, the dispersal pathways for the introduction and spread of Ae. albopictus in numerous countries remains unknown, especially from the 1990s onwards. Conclusions This review identified the main known and suspected dispersal pathways of human-mediated Ae. albopictus dispersal leading to the first introduction of Ae. albopictus into new countries and highlighted gaps in our understanding of Ae. albopictus dispersal pathways. Relevant advances in vector surveillance and genomic tracking techniques are presented and discussed in the context of improving vector surveillance. Graphical Abstract

Multiple invasions, Wolbachia and human-aided transport drive the genetic variability of Aedes albopictus in the Iberian Peninsula

“…Previous studies have also highlighted that, although Ae. albopictus has low natural dispersal capabilities, human-aided transport (especially cars) has probably facilitated significantly the tiger mosquito’s movement and invasion process 29 , 30 , 32 , 41 . Our findings are consistent with these but go a step further by suggesting that the “hitchhiking” of Ae.…”

“…albopictus and promoting regional gene flow. Mosquito movement can be affected by human activities like commuting and human-made structures like roads, which combined act as bridges for dispersal by favouring gene flow and promoting genetic mixing 32 .…”

“…albopictus and promoting regional gene flow. Mosquito movement can be affected by human activities like commuting and human-made structures like roads, which combined act as bridges for dispersal by favouring gene flow and promoting genetic mixing 32 . At a much broader spatial scale, we find a general lack of genetic structure and geographic consistency among haplotypes across the large expanse of the Iberian Peninsula, with numerous haplotypes shared among several distant areas (e.g.…”

“…25,27,28 ). Furthermore, in Europe human transportation networks have been shown to have facilitated the spread of this mosquito and conditioned its genetic and demographic patterns [29][30][31][32] .…”

Genetic Diversity of Dengue Vector Aedes albopictus Collected from South Korea, Japan, and Laos

“…Ae. albopictus has expanded its distribution areas through human activities in Southeast Asia, which is its place of origin, and is currently found in all parts of the world except Antarctica [ 35 , 36 , 37 ]. The establishment of successful mosquito control programs can be effective when based on proper knowledge of genetic variation and population dynamics [ 38 , 39 ].…”