Cases of dangerous bacteria doubled in Florida following Hurricane Helene

Hurricane Helene left not only a path of destruction after landing in Florida as a Category 4 hurricane, but also a rise in dangerous bacteria, new data shows.

The number of cases of vibrio vulnificus, a type of bacteria known to increase in concentration during heavy rain or flooding, doubled in Florida following Helene’s landfall on Sept. 26, according to data from the state's Department of Health.

There have been 38 confirmed cases of vibrio vulnificus since Helene made landfall, bringing the total in the state to 76.

Nationally, around 150 to 200 cases of vibrio vulnificus are reported each year.

The infection can lead to necrotizing fasciitis, also known as ‘flesh-eating disease’, a severe infection in which the flesh around an open wound dies. Many people may require intensive care or limb amputations and about one in five people with this infection die, sometimes within one to two days of becoming ill, according to the U.S. Centers for Disease Control and Prevention.

Both Helene and Milton, a hurricane that made landfall in Siesta Key on Oct. 10 as Category 3 storm, brought record-breaking storm surge to Florida's Gulf Coast. The storm surge causes salt water to mix with fresh water, becoming a breeding place for bacteria, according to Dr. Scott Rivkees, a pediatric endocrinologist and physician-scientist who served as Florida's state surgeon general and secretary of health from 2019 to 2021.

"Where you have salt water meeting fresh water, this is where vibrio can thrive," Rivkees told ABC News. "And if individuals are exposed to brackish water and they have an open cut, or they're immunocompromised, such as having cancer, vibrio can take hold."

Rivkees, also a professor at the Brown University School of Public Health, described vibrio as "one of the most aggressive" types of bacterial infections that exist, and said infection can lead to skin removal, amputation or even death.

He said that long after a hurricane has passed, water, specifically floodwater, remains the biggest risk to humans.

"People need to recognize that more people will die after a storm than during the storm, and drowning is the major thing that we worry about," Rivkees said, adding that a major danger is driving a car through floodwaters.

In addition to drowning in floodwaters, people may be unknowingly exposed to dangers, especially if they have open wounds or develop cuts while they are working to clear debris.

Rivkees said in Florida, septic systems can spill into groundwater during hurricanes, causing the kind of brackish water where bacteria can thrive.

Boats damaged during hurricanes can also unleash septic holding tanks and marine fuel oils that end up mixed in with floodwaters in residential areas, posing another health risk, according to Rivkees.

In Florida's climate, floodwaters can become breeding grounds for mosquitoes, according to Rivkees, as well as places where threatening wildlife like water moccasins are found after their natural habitats were disrupted by the storm.

Dangerous debris, including sharp or large objects or downed wires, can often be hidden under muddy floodwaters, also leading to injury.

In Cedar Key, about 100 miles from where Helene made landfall, local medical providers saw a rise in cases of cellulitis, a bacterial skin infection that can occur after exposure to flood water, according to Tami Wilkes, APRN, who works at Cedar Key Healthcare, a local medical clinic.

Wilkes told ABC News the clinic also saw a rise in patients with lacerations, cases of asthma and bronchitis, and those in need of tetanus injections, showing the multiple health risks that hurricane floodwaters can bring.

"The county health department brought a bus to provide tetanus injections and we worked together providing sutures, antibiotics and nebulizer treatments in effort to meet the needs," Wilkes told ABC News, adding, "We are working long hours to get the medical office back open."

Safety tips to know

Rivkees said the most important thing residents can do after a hurricane is to listen to public safety officials' guidance on when it is safe to return.

"There's always a temptation to get back there as soon as you can, and you're going to have first responders there who are trying to clear the area and make sure that the area is safe and secure," he explained. "Individuals should really listen for their public officials to give the all clear when it is safe to return, because otherwise that could help impede the response."

If in an area where floodwater is present, Rivkees said people should be aware of any open wounds on their body and should always wear protective clothing.

The U.S. Centers for Disease Control and Prevention recommends people wear rubber boots, rubber gloves and goggles if they "must" enter floodwater.

The CDC also says people should sanitize after coming into contact with floodwater, including using soap and clean water for their skin and hot water and detergent for clothes.

Open wounds that come into contact with floodwater should also be cleaned with soap and clean water and checked by a medical provider if necessary, according to the CDC.

Signs that an infection is serious enough for medical attention include redness, swelling or soreness around an open wound, any sign of a foreign object embedded in the wound and other physical symptoms including fever, nausea, confusion, extreme pain, shortness of breath or high heart rate, according to the CDC.

Editor's note: This report was originally published on Oct. 9, 2024.