Modeling the complex hatching and development of Aedes aegypti in temperate climates.

ROMEO AZNAR, V; OTERO, M. J.; M S DE MAJO; S FISCHER; H G SOLARI

ECOLOGICAL MODELLING

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2013 vol. 253 p. 44 - 55

0304-3800

Here, we present and discuss a compartmental stochastic model for Aedes aegypti conceived as a math-ematical structure able to interpolate and extrapolate (predict) biological phenomena, and direct theattention to biological matters that need experimental elucidation. The model incorporates weatherinformation in the form of daily temperatures and rain and pays particular attention to determiningfactors in temperate climates. Sufficiently large rains trigger egg hatching, which in turn leads to peaksin larval densities. Hatching is inhibited by the absence of bacteria (Gillett effect), a mechanism of rel-evance during the winter season and in seasons with isolated rains. The model also incorporates egghatching independent of rains. Both egg hatching and larval development depend on the availability offood, which is modeled as bacteria produced at rates that depend on the temperature. Larval mortalityand pupation rates depend on the larvae to bacteria ratio. The results of the model for egg laying activ-ity were compared with field records during a normal season and a drought. Both the model and therecords indicate that the egg laying activity of Ae. aegypti is not zero during the drought and recoversquickly when normal weather is reestablished. We studied the sensitivity of the model to different setsof physiological parameters published for a few different local populations of this species, and found thatthere is an important sensitivity to local characteristics that will affect some predictions of the model.We emphasize that if the information is going to be used to evaluate control methods, the life cycle of themosquito must be studied for the local strain under the local environmental conditions (including food).We showed that the adult populations produced by the model are insensitive to certain combinations ofparameters and that this insensitivity is related to the variability reported for different strains obtainedfrom closely located places. When the model is considered in a larger biological context, it indicates thatsome standard procedures performed to measure the life cycle of Ae. aegypti in the laboratory might havea determining influence in the results.