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DeGennaro, M.

Publications and source records attributed to DeGennaro, M..

2 recordsLinked to original sources
bioRxiv2019

Increased temperatures reduce the vectorial capacity of Aedes mosquitoes for Zika virus

Rapid and significant range expansion of both ZIKV and its Aedes host species has resulted in ZIKV being declared a global health threat. Mean temperatures are projected to increase globally, likely resulting in alterations of the transmission potential of mosquito-borne pathogens. The relationship between temperature and ZIKV transmission has not been well characterised for Aedes aegypti and Aedes albopictus.\n\nTo understand the effect of diurnal temperature range on the vectorial capacity of Aedes aegypti and Aedes albopictus for ZIKV, factors contributing to transmission potential were measured at different temperature regimens. Their longevity and blood feeding rates were assessed, and vector competence was determined following feeding on blood meals with 8.3 log10 PFU/ml ZIKV.\n\nHigher temperature resulted in decreased longevity of Ae. aegypti [Log-rank (Mantel-Cox) Test, Chi-square, df 35.66, 5 P (<0.0001)] and a significant decrease in blood feeding rates across groups [Z score (-5.8478) P (0.0444)]. Temperature had a population and species-specific impact on ZIKV infection rates. Overall, Ae. albopictus reared at the lowest temperature regimen demonstrated the highest vectorial capacity (1.63) and the highest transmission efficiency (57%). Temperature increases decreased vectorial capacity across groups, yet the largest decreases were measured for Ae. aegypti.\n\nThe results of this study suggest that future climate change could significantly impact vector competence, blood feeding behavior and longevity, and therefore decrease the overall vectorial capacity of Aedes mosquitoes. It is also clear that this impact is likely to be both species and population-specific.

microbiology↗
bioRxiv2019

Geosmin attracts Aedes aegypti mosquitoes to oviposition sites

Geosmin is one of the most recognizable and common microbial smells on the planet. Some insects, like mosquitoes, require microbial-rich environments for their progeny, whereas for other insects such microbes may prove dangerous. In the vinegar fly Drosophila melanogaster, geosmin is decoded in a remarkably precise fashion and induces aversion, presumably signaling the presence of harmful microbes. We have here investigated the effect of geosmin on the behavior of the yellow fever mosquito Aedes aegypti. In contrast to flies, geosmin is not aversive in mosquitoes but stimulates egg-laying site selection. Female mosquitoes could associate geosmin with microbes, including cyanobacteria consumed by larvae, who also find geosmin - as well as geosmin producing cyanobacteria - attractive. Using in vivo multiphoton imaging from mosquitoes with pan-neural expression of the calcium reporter GCaMP6s, we show that Ae. aegypti code geosmin in a similar fashion to flies, i.e. with extreme sensitivity and with a high degree of selectivity. We further demonstrate that geosmin can be used as bait under field conditions, and finally we show that geosmin, which is both expensive and difficult to obtain, can be substituted by beetroot peel extract, providing a cheap and viable mean of mosquito control and surveillance in developing countries.

neuroscience↗