New Invasive Mosquito Species Found in South Florida

VERO BEACH, Fla. – A new mosquito species capable of transmitting disease, Aedes scapularis, has arrived in Florida and shows signs it could survive across multiple urban and rural habitats, posing a potential public health risk. 

In a new study from the University of Florida’s Institute of Food and Agricultural Sciences (UF/IFAS), scientists predict where in Florida environmental conditions may be suitable for this new species to spread, now that it has invaded the Florida peninsula.

This new, nonnative mosquito the team discovered and announced last November can transmit yellow fever virus, Venezuelan equine encephalitis virus, dog heartworm and other pathogens to humans and animals. It has a wide range, from Texas to parts of South America and throughout much of the Caribbean. The species is widespread in Miami-Dade and Broward counties. 

In the latest study –– a follow-up published in the Multidisciplinary Digital Publishing Institute journal Insects –– scientists at the UF/IFAS Florida Medical Entomology Laboratory indicated through model predictions that suitable environments for Aedes scapularis could be present along coastal counties in much of Florida. More specifically, the areas along Florida’s Atlantic and Gulf coastlines predicted to be highly suitable for this species are from Monroe and Miami-Dade counties, north to Martin County on the Atlantic Coast, and in Citrus County on the Gulf Coast.   

“At least 16 Florida counties were predicted to be highly suitable for Aedes scapularis, suggesting that vigilance is needed by mosquito control and public health agencies to recognize the further spread of this vector,” said Lawrence Reeves, a research scientist at the center in Vero Beach and co-author in the report.   

The scientists used a process known as ecological niche modeling, which uses a machine-learning algorithm to predict the potential distribution of a species across the landscape. The process is often used to determine areas that could be invaded by a nonnative species.  

“We are able to predict the potential distribution of Aedes scapularis in Florida and parts of the southeastern United States, including Texas, Louisiana, Mississippi, Georgia and parts of South Carolina,” said Lindsay Campbell, assistant professor of entomology and nematology at the research center. “This model compares environmental and climate data from the native range of this mosquito in Central and South America with similar data from the southeastern United States and Florida to predict where areas might be suitable for the species.” 

The output of the model is a map showing suitable environments where the species could potentially spread, and while the map does not show the probability that Aedes scapularis is located at an exact location, it can be used as a tool to identify where the environment could be suitable for this mosquito as it continues to spread across Florida.   

“This information is useful to mosquito control districts monitoring for Aedes scapularis now that it has reached the mainland, and it can be updated regularly,” said Campbell.   

The model included Aedes scapularis records across South, Central and portions of North America, and from multiple Caribbean islands to help make accurate predictions. 

In 2020, the team collected 121 Aedes scapularis specimens between Florida City in southern Miami-Dade County and the Pompano Beach area in northern Broward County. By combining these records, scientists incorporated vital information about where the mosquito had been observed, with humidity and temperature values that were acquired from satellite remote–sensing data to make model predictions.

“The use of satellite remote–sensing data products enabled us to incorporate environmental conditions across the full geographic range of this species and to make a prediction about its potential distribution across the southern United States,” said Campbell.  

The next steps for research of this new species are to continue to work with colleagues in the Florida mosquito control districts to incorporate new observations of this species into updated models. Additionally, scientists have the opportunity to observe how this species is moving across the landscape and what types of local environments facilitate or limit its geographic spread. 

“This information will provide valuable insight into potential risks associated with Aedes scapularis while also providing important information about potential outcomes for additional mosquito species introductions,” said Reeves.

Source: UF-IFAS