How Hurricanes Irma and Maria affected population dynamics and nutrient content of Aedes aegypti in San Juan Puerto Rico, U.S.A; socioeconomic and temporal factors.

Abstract

Urban environments often contain mosquito species that are responsible for transmitting medically important pathogens to humans. Large disturbance events, like hurricanes, can devastate large urban areas, especially in the tropics, however little data exist for how these storms affect vector populations. During September 2017 Hurricanes Irma (category 5) and Maria (category 4) passed in proximity to the island of Puerto Rico, U.S.A., causing significant damage to the built environment and significantly altering the abiotic environment including the removal of the plant canopy. We measured adult Aedes aegypti populations, the main vector of several pathogens, and larval containers across eight neighborhoods in San Juan, the capitol, that varied in socioeconomic status (SES) across eight sampling periods over 17 months following the storms. We also analyzed the nutrient content (%N, %C, C:N) and stable isotopes (δ¹⁵N, δ¹³C) from adults and isotopes from containers to assess how the nutrient environments changed post hurricanes. Mosquito population sizes were invariant throughout sampling, although more females were collected in lower SES neighborhoods that were more enriched in δ¹⁵N compared to higher SES locations. We did find that the storms altered the stoichiometric content of adults, with lower C:N values right after compared to a year later; larval containers showed an increase in δ¹⁵N through time. The lack of any interactive effects of the storms on specific neighborhoods suggests that Irma and Maria affected all locations equally, however, the storms altered the nutrient content of both adults and larval containers, a result with implications for pathogen transmission.