Can Manatees Get West Nile Virus?

Slow-moving manatees like to live in shallow water and they come up for air every 3 to 5 minutes, making them easy targets for mosquitoes. UF/IFAS FILE PHOTO

Greetings! We all know that nasty itch from a mosquito bite, along with the possibility of the pesky inscet injecting a disease such as West Nile Virus. With that said, can a mosquito bite a manatee and possibly give it West Nile Virus? Absolutely! Mosquitoes which transmit diseases such as West Nile don’t just bite humans, horses or birds. Recent research explains they can actually “attack slow-moving manatees!” 

Research says, “West Nile virus is spread by the southern house mosquito and other Culex species, and is now considered an endemic disease in the southern United States. More than 40 cases of human infections have been registered this year in Miami-Dade.” Birds are commonly infected, and a University of Florida study recently stated, “that manatees at Everglades National Park also are vulnerable to bites by Culex mosquitoes and could potentially be infected by the viruses they carry.” Lawrence Reeves, an entomologist at the Florida Medical Entomology Laboratory of UF/IFAS in Vero Beach who is the lead author of this study published in Scientific Report said, “We know that the mosquitoes bite manatees and that they inject saliva that could carry viruses.” Reeves took a photo of a Culex mosquito biting a manatee at the marina of the Flamingo Visitor Center at Everglades National Park.

However, even though this study did not document any manatee infections from the West Nile Virus, other marine mammals such as “captive killer whales and Atlantic bottlenose dolphins have become infected and died from mosquito-borne viruses.” So, this obviously raises questions about the manatees living in Florida’s waterways.

The West Indian manatee (Florida manatee and Antillean manatee) had been classified as an endangered species until 2017, when there was “evidence of a recovery … [that] led to a down-listing to threatened status. Still, these mammals remain under state and federal protection because of the risk of habitat loss and boat strikes.”

Reeves continued and said, “From a conservation perspective, it’s important to learn more about how virus-infected mosquitoes interact with these animals. These arboviruses could potentially be a health threat to marine mammals.”

It was between the years 2015 and 2018 Reeves conducted research at Everglades National Park, watching mosquitoes interact with local wildlife from the Flamingo Marina. Using a telephoto lens, he looked for mosquitoes flying near manatees and he was able to record three kinds of mosquitoes landing on and biting the mammals when they were swimming on the surface. These three mosquito types were; Aedes, Anopheles, and Culex, which interacted with the manatees. In addition to West Nile, “these species are known to carry Eastern equine encephalitis virusSt. Louis encephalitis virus and Venezuelan equine encephalitis virus, which are [rarer] and can lead to serious illnesses and death in horses and humans.”

Lawrence Reeves was able to document these mosquitoes biting the thick manatee skin. This means that the mosquito saliva, which carries the virus, was likely injected into the marine mammals. Because manatees live in shallow, slow-moving water found in rivers, estuaries, saltwater bays and canals, they need to surface for air, which makes these marine mammals very easy targets for mosquitoes. Reeves explained, “Like humans and other mammals, manatees emit a plume of carbon dioxide when they breathe, which attracts mosquitoes up to 50 feet away.”

A 2017 study by Florida Atlantic University found the exposure to West Nile virus “has also been detected in wild Atlantic bottlenose dolphins.”

Reeves explained, manatees could potentially be tested to reveal what happens after they are bitten by virus-carrying mosquitoes.” 

Stay tuned for more of my blogs!

If you see any sick or injured manatees, please call the Florida Fish and Wildlife Conservation Commission at: 1-888-404-FWCC. They are the folks who are responsible for rescuing us in Florida.

Here’s the Save the Manatee Club link to learn more about us manatees …

Here’s a cool link for you to learn more about how we’re rescued and brought into rehabilitation …

~ Kobee Manatee

Related Posts

Manatee Facts – Knowledge Challenge 1 (October 3, 2019)

Manatee Facts – Knowledge Challenge 2 (October 16, 2019)

Manatee Facts – Knowledge Challenge 3 (October 28, 2019)

Manatee Facts – Knowledge Challenge 4 (November 21, 2019)

Manatee Facts – Knowledge Challenge 5 (December 4, 2019)