Influence of temperature on immature development, survival, longevity, fecundity, and gonotrophic cycles of Aedes albopictus, vector of chikungunya and dengue in the Indian Ocean.

Aedes albopictus is a mosquito originating from Asia, which has extended its range worldwide the last decades. It is a competent vector for several arboviruses. It was first described in La Réunion (an island of the South West part of the Indian Ocean) in 1913. Since then, it has become the dominant Aedes species and a serious threat to public health, especially during the two last arboviruses outbreaks of dengue (1977) and chikungunya (2005-2006). Despite its pest status, data on the biology of this vector are scarce, especially the population present in the Indian Ocean (IO), which has never been studied in detail. Therefore, the immature development, survival, longevity, fecundity, and gonotrophic cycles of Ae. albopictus were studied for an F2 population of the IO. These biological parameters were studied in controlled conditions at eight constant temperatures (5, 10, 15, 20, 25, 30, 35, and 40 degrees C). The minimal threshold of immature stages development was found at 10.4 degrees C and its optimum at 29.7 degrees C. The shortest periods for immature development were found at 30 degrees C, with in average of 8.8 d. The optimum intrinsic rate of growth (r) was observed between 25 and 30 degrees C. The gonotrophic cycles were also evaluated, and the shortest cycles were found at 30 degrees C (mean, 3.5 d). Those results are according to the field repartition of this species in La Réunion, allowing Ae. albopictus survival at a large range of temperatures.