Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Effect of larval competition on populations of the dengue vector collected in Medellín, Colombia.

Abstract

Introduction: Aedes aegypti is the vector transmitting the dengue virus. Larval density may affect adult life, with an impact on viral transmission capacity. Objective: determine the effect of larval competition caused by high density in Aedes aegypti colonies from areas of high and low dengue incidence in the city of Medellín, Colombia, and in a reference colony in the laboratory. Methods: the three colonies were evaluated for larval development and survival time, as well as size and survival time in adults. Results: it was found that in high density conditions larval competition significantly shortened development and survival time in the last larval stages. High density during the larval stage also brought about changes in adults from the three colonies, represented by a significantly reduced size and a decrease in survival time (the latter only in the field colonies). Conclusion: no differences in competitive effect were found between the field colonies from areas with unequal dengue incidence in Medellín. However, the difference in the response obtained from the laboratory colony in contrast to the field colony, points to the need to evaluate the ecological parameters of wild Aedes aegypti populations to obtain a more accurate view of the behavior of the vector. Laboratory studies in progress will make it possible to know whether the differences found between the colonies affect the competence of Aedes aegypti for dengue virus infection.