Great, Now Florida Has a Mosquito That Can Carry Yellow Fever

Scientists in Florida have confirmed that there’s a new breed of mosquito in town that can carry a very dangerous set of diseases, including yellow fever. And while it’s only in two counties in the state right now, a new paper indicates that its range could spread across the Sunshine State.

The new mosquito is known as Aedes scapularis, and its usual habitat is the tropics, ranging all over Central America and down to portions of South America and into the Caribbean. There’s only one recorded instance of it making it to Florida, though, when larval samples were found in the middle of the Florida Keys in 1945.

But in 2019, entomologists at the University of Florida found specimens of this skeeter during a sample collection in the Everglades. In a study conducted last year, scientists confirmed that the mosquitoes were present in healthy numbers throughout Miami-Dade and Broward counties. Now, in a follow-up paper, published this month in the journal Insects, scientists use environmental modeling to project that Aedes scapularis could spread along the Florida coast.

In its usual habitat, Aedes scapularis has been linked to a number of serious diseases, including yellow fever, which is all but eradicated in the U.S.; the last outbreak was in New Orleans in 1905. There’s also concern that mosquitoes like Aedes scapularis, which likes to bite both humans and animals, could trigger what are known as spillover events. Those happen when diseases spread from one species to another, similar to how covid-19 was likely first transmitted to humans via animals. (To be clear, the mosquito is not a known transmitter of covid-19, so at least Floridians don’t have to worry about that.)

The new research shows that Aedes scapularis likely made it to Florida via human travel and commerce, but climate change could play a role in its spread throughout the peninsula. Warmer temperatures will allow the bug to propagate northward. Though there haven’t been any cases of yellow fever detected where the mosquito is, they are known to carry the disease in their native range, which raises the risk they could in Florida.

It’s a familiar story as rising temperatures allow disease-carrying mosquitoes to move poleward. The Lancet recently found that warmer temperatures were responsible for spreading dengue fever to new places; 2018 was the second-worst year for dengue fever spread since record-keeping began, and nine of the 10 worst years have occurred since 2000. Another kind of asshole Florida mosquito tourist, Aedes aegypti, infected more than 50 people with the disease last summer. Research on mosquitoes that can transmit Zika virus has reached similar conclusions.

Scientists have also warned that increasingly close contact between humans and nature is upping the risk of more spillover events where animal-born illnesses are finding more and more human hosts. Findings released last year show spending just $40 to $58 billion annually could help stave off dangerous disease outbreaks, which is a fraction of the cost of a major disease outbreak. 

Hopefully we won’t see another mosquito-led public health crisis on the heels of this neverending pandemic. But if you’re planning on going to Disney World after you get vaccinated this summer, don’t forget to pack bug repellant just in case.