Urbanization creates diverse aquatic habitats for immature mosquitoes in urban areas

Abstract

Global increases in temperatures and urbanization are impacting the epidemiology of mosquito-borne diseases. Urbanization processes create suitable habitats for vector mosquitoes in which there are a reduced number of predators, and human hosts are widely available. We hypothesize that mosquito vector species, especially Aedes aegypti, are locally concentrated primarily in those specific habitats at the neighborhood levels that provide suitable conditions and environmental resources needed for mosquito survival. Determining how mosquito vector species composition and abundance depend on environmental resources across habitats addresses where different types of vector control need to be applied. Therefore, our goal was to analyze and identify the most productive aquatic habitats for mosquitoes in Miami-Dade County, Florida. Immature mosquito surveys were conducted throughout Miami-Dade County from April 2018 to June 2019, totaling 2,488 inspections. Mosquitoes were collected in 76 different types of aquatic habitats scattered throughout 141 neighborhoods located in the urbanized areas of Miami-Dade County. A total of 44,599 immature mosquitoes were collected and Ae. aegypti was the most common and abundant species, comprising 43% of all specimens collected. Aedes aegypti was primarily found in buckets, bromeliads, and flower pots, concentrated in specific neighborhoods. Our results showed that aquatic habitats created by anthropogenic land-use modifications (e.g., ornamental bromeliads, buckets, etc.) were positively correlated with the abundance of Ae. aegypti. This study serves to identify how vector mosquitoes utilize the resources available in urban environments and to determine the exact role of these specific urban features in supporting populations of vector mosquito species. Ultimately, the identification of modifiable urban features will allow the development of targeted mosquito control strategies optimized to preventatively control vector mosquitoes in urban areas.

Proliferation of Aedes aegypti in urban environments mediated by the availability of key aquatic habitats

“…For example, ornamental bromeliads are extensively used in landscaping in Miami and are known for breeding Ae. aegypti in great numbers 31 , 55 , and as highlighted by this study, can have a major role in their proliferation in urban areas. However, in Brazil bromeliads are not considered important for mosquito management and control actions in the cities of Vitória 56 and Rio de Janeiro 57 , yet are considered important in the city of São Paulo 58 .…”

“…Controlling populations of vector mosquito species in urban environments is a major challenge. Aedes aegypti is well adapted to and will successfully exploit many artificial and natural habitats present in urban environments, presenting a major challenge for the development of control strategies 31 . Reactive control strategies based on the use of larvicide and adulticide are widely ineffective due to the inherent difficulty in reaching cryptic breeding habitats and resting adult mosquitoes 32 .…”

“…aegypti . Therefore, our objective was to leverage on the immature mosquito surveillance system based on requested by citizen complaints through 311 calls 31 to determine what are the most important aquatic habitats in the proliferation of Ae. aegypti in Miami and which aquatic habitats should be prioritized in mosquito management and control strategies.…”

Cemeteries in Miami-Dade County, Florida are important areas to be targeted in mosquito management and control efforts

“…aegypti larvae and 2,997 pupae were collected, while only 325 Ae. albopictus larvae and 65 pupae were collected in the same period [54]. The fact that Ae.…”

“…Even though the role of cemeteries in the proliferation of vector mosquitoes has been studied for many years [32], not only the mosquito community composition varies from place to place but resource availability, local variation in climate and the increase in global temperatures due to global warming also have to be taken into consideration [54,55]. Constant surveillance of problematic areas for the proliferation of vector mosquitoes in urban areas is key to not only better understand how mosquito species may be exploiting these habitats but also to assess the spreading of invasive species in urban areas.…”