Macroclimate Determines the Global Range Limit of Aedes aegypti

Abstract

Aedes aegypti is the main vector of dengue and a number of other diseases worldwide. Because of the domestic nature of this mosquito, the relative importance of macroclimate in shaping its distribution has been a controversial issue. We have captured here the worldwide macroclimatic conditions occupied by A. aegypti in the last century. We assessed the ability of this information to predict the species' observed distribution using supra-continental spatially-uncorrelated data. We further projected the distribution of the colonized climates in the near future (2010-2039) under two climate-change scenarios. Our results indicate that the macroclimate is largely responsible for setting the maximum range limit of A. aegypti worldwide and that in the near future, relatively wide areas beyond this limit will receive macroclimates previously occupied by the species. By comparing our projections, with those from a previous model based strictly on species-climate relationships (i.e., excluding human influence), we also found support for the hypothesis that much of the species' range in temperate and subtropical regions is being sustained by artificial environments. Altogether, these findings suggest that, if the domestic environments commonly exploited by this species are available in the newly suitable areas, its distribution may expand considerably in the near future.

Chikungunya virus infection in developing countries - What should we do?

“…There are reports suggesting that some of the vector borne viruses (arbovirus) such as Chikungunya, Dengue and Zika viruses are evolving them to expand their natural principal vectors (Nasci, 2014). Moreover, vector biology including their distribution is greatly under the influence of climate change (global warming) and habitat changes (Capinha et al, 2014;Khormi and Kumar, 2014). It is therefore now vital to know the extent of distribution of CHIKV vector in nature for successful vector control to reduce or stop the spread of pathogen they carry.…”

The Burden of Dengue and Chikungunya Worldwide: Implications for the Southern United States and California

“…14,43–46 Macroclimate is another important factor in predicting the range of Aedes mosquitoes and as climate change threatens to expand the area hospitable to this species, the need for vector control efforts as well as novel vaccines and antiviral therapies for dengue and other flaviviruses will certainly grow. 47 The secondary vector, Aedes albopictus , has been implicated in previous outbreaks of dengue and chikungunya in more temperate climates, however some research has suggested that this vector species is much less efficient at transmitting the virus than Aedes aegypti , perhaps due to native Wolbachia infection. 48,49 Alternatively, recent modeling approaches have suggested that Aedes albopictus may be even more efficient than Aedes aegypti at dengue transmission, particularly when considering the longer lifespan of this species.…”

“…88,89 Furthermore, the Aedes aegypti vector in Mexico appears to be spreading into elevations and climes previously thought to be inhospitable. 47,89,90 Indeed, the first locally-acquired cases of dengue in Baja California state, Mexico, were reported in November, 2014 in addition to an above-average number of imported cases. 72 The socioeconomic differences that exist between Texas and Mexico that have been previously described as protective against a dengue outbreaks are likely also applicable to the cross-border situation in California, however these factors are not entirely preventative.…”

The interplay of vaccination and vector control on small dengue networks

“…The principal vector of dengue, the invasive species A. aegypti , is distributed throughout tropical regions (Capinha et al, 2014). This vector is successful in colonising high density human populations, and often adult mosquitoes do not disperse very far, with evidence that some inhabit single households throughout their lives (Stoddard et al, 2013).…”