How do I bite thee? Let me count the ways: Heterogeneity and temperature dependence in Ae. aegypti biting habits drive individual mosquito arbovirus transmission potential

Abstract

AbstractIn models of mosquito-borne transmission, biting rate is the most influential parameter, and understanding the role of temperature on this process is important for assessing the transmission potential of arboviruses like dengue (DENV). Further, the process of biting is assumed to be relatively homogeneous across individuals, with time-between-bites described by an exponentially distributed process. However, these assumptions have not been addressed through laboratory experimentation. We experimentally determined daily biting habits of Ae. aegypti at three temperatures (24°C, 28°C, and 32°C) and determined that there was a high degree of individual heterogeneity in biting habits (number of bites, timing of bites, etc.). There was a significantly higher proportion of females that bit at 28°C compared to both 24°C and 32°C. We further explored the consequences of biting heterogeneity using an individual-based model designed to examine whether a particular biting profile determines whether a mosquito is more or less likely to 1) become exposed given a single index case of DENV and 2) transmit to a susceptible individual. Our results indicate that biting is heterogeneous among individuals and this heterogeneity affects transmission potential of DENV. Understanding individual-level heterogeneity in biting is important and may suggest a role for high-frequency biters as significant contributors to the transmission of DENV.