“Deadly Bacteria Spread across Oceans as Water Temperatures Rise”
In the Scientific American's ClimateWire, Umair Irfan published about how the temperature rise of the world's oceans will impact the spread of deadly bacteria such as Cholera. Johns Hopkins Bloomberg School of Public Health's professor Rita Colwell explains how this is grounded in a study on plankton:
Deadly bacteria are spreading through the oceans as waters warm up, and are increasing infection risks, according to a new study.
Multiple species of rod-shaped Vibrio bacteria live in the world’s oceans, and their populations rise and fall based on many different variables, changing the likelihood of making people sick.
A report published yesterday in the journal Proceedings of the National Academy of Sciencesexamined the role of the changing climate in Vibrio infections.
In the United States, Vibrio bacteria cause about 80,000 illnesses and 100 deaths each year. The species that causes the devastating diarrheal disease cholera, Vibrio cholerae, is responsible for up to 142,000 deaths around the world annually, according to the World Health Organization.
Infection risks tend to rise when water temperatures go up, so researchers sought to figure out whether rising temperatures have played a role in the bacteria’s abundance.
Co-author Rita Colwell, a professor at the University of Maryland and the Johns Hopkins Bloomberg School of Public Health, explained that her team looked at records of plankton, tiny organisms that drift and float at the ocean’s surface. This includes small animals as well as bacteria.
“We picked up stored samples of plankton collected every year for 50 years,” Colwell said. “What’s beautiful about this is it’s ground truth. It’s actually taking measurements on the ground.”
Experts explain how the spread of bacteria will impact countries differently based on their infrastructure and treatment facilities:
For most developed countries, good water management can mitigate much of the harm associated with an increase in ocean bacteria. “As long as those treatment facilities remain intact, I don’t think we’re going to see outbreaks of cholera [in Europe and the United States] again,” Colwell said.
The bigger problems may lurk in developing countries, where sanitation systems are not as good and may be vulnerable to extreme weather like floods and typhoons. An increased abundance of bacteria may pose a greater infection risk as salt water and brackish water flood coastal areas.
“That’s going to be a problem,” Colwell said.