In September, the storm Ian hit the southwest coast of Florida, bringing storm surge as high as 13 feet in the coastal town of Fort Myers. Warm, brackish water in the Gulf flooded homes and businesses as well as sewers, sewage pumps and septic tanks. As torrential wind and rain mixed everything together into a giant mud, a highly adaptable microscopic creature gained a foothold: a species of “carnivorous” bug known as Vibrio vulnificus.
28 people have been infected with this bacterium, which can rapidly degrade skin cells, leaching iron from the blood and leading to multi-organ failure. Seven of those infected died. “When you’re in a tropical environment with standing water a lot of scum and whatever else is baking in the sun – it’s the perfect cocktail,” said James Williams, an environmental specialist at the Florida Department. perfect for this bacteria to grow. Health.
Cases have dropped as floodwaters receded, with no new infections reported after October 13. But many researchers, including Dayle Daines, a microbiologist at Old Dominion University in Virginia , believe V. vulnificus and its pathogenic cousins, including 11 other Vibrio species that are harmful to humans, can added value in the coming decades as climate change reshapes the aquatic landscape. Storms are increasing in intensity, flooding is breaking records and warmer ocean waters are stretching further north. Vibrio bacteria thrive in warm water. They are also moisture-loving, which means they thrive in slightly salty, brackish waters, like the floodwaters that lingered after Hurricane Ian.
There are more than 100 known species of Vibrio. A small part causes disease in humans, the main culprit is V. cholerae– the pathogen that causes cholera—V. parahaemolyticusand V. vulnificus. One recent analysis led by the Environmental Protection Agency found that Vibrio infection rates could increase by 50 to 100 percent in the United States by 2090, increasing the annual costs to tackle these diseases from just over 2 billion dollars up to 7 billion dollars.
Vibriosis outbreaks are also expected to migrate further north as temperatures rise and sea levels rise. An outbreak in Scandinavia in 2014 infected nearly 90 people, some within 100 miles of the Arctic Circle. The culprit: a persistent heatwave that caused sea surface temperatures to reach an all-time high in that region. “If you have an electric current and you have a heat wave, you can get Vibrio,” says Daines. She says rising temperatures are also driving people to the beach, which is more likely to be exposed.
Flooding increases people’s exposure to bacteria-laden water, and therefore increases the risk of infection. It also has the effect of making water-borne bacteria more dangerous. In Florida, strong Ian high tides caused old, damaged pipes and septic tanks to leak wastewater into surrounding floodwaters. Vibrio species can then easily combine with other bacteria and swap genes with them, including genes for antibiotic resistance. Researchers believe there will be more opportunities for these gene mixing events.
