According to the CDC, there are about a dozen species of the marine prokaryote called Vibrio, known to cause vibriosis in humans. The Vibrio species that cause vibriosis naturally live in brackish or salt water along the coastal regions of the world.
People can get sick from eating raw or undercooked seafood, or exposing an open wound to seawater. In the United States, Vibrio causes an estimated 80,000 illnesses and 100 deaths every year. The Associated Press reports that the CDC also says that most cases of vibriosis are not reported and therefore not confirmed, but there has been a distinct rise in confirmed cases since 1990.
“It’s a remarkable increase on an annual basis,” said the study’s lead author Rita Colwell, with the Maryland Pathogen Research Institute and Center of Bioinformatics and Computational Biology, at the University of Maryland, in College Park.
In the study, Colwell and her colleagues report that “for the first time to our knowledge, experimental evidence is provided on the link between multidecadal climatic variability in the temperate North Atlantic and the presence and spread of Vibrios, which are responsible for several infections in both humans and animals.”
The research team used DNA and fifty years worth of records that documented plankton, water temperatures and diseases covering North America and Europe that resulted in a comprehensive picture of the relationship with warming temperatures and the increase in Vibrio illnesses.
“We picked up stored samples of plankton collected every year for 50 years,” Colwell said, according to Scientific American. “What’s beautiful about this is it’s ground truth. It’s actually taking measurements on the ground.”
The samples were collected from nine areas in the North Atlantic and the North Sea between 1958 and 2011. It was also documented that sea surface temperatures had risen about 1.5 degrees Celsius during the same time frame. The team measured the presence and abundance of Vibrio bacteria in the collected samples and compared their findings to the data on the climate records.
Of particular interest is the rise in the number of cases in Alaska, where Vibrio infections were unheard of until recently. Colwell also cited the increase in cases of vibrio illnesses in northern Europe due to people swimming in the ocean during heat waves between 1994 and 2010.
“Now we have linked very directly the increase and the trend in the number of cases, so it’s all coming together in great detail,” Colwell said.
This very interesting study, “Climate influence on Vibrio and associated human diseases during the past half-century in the coastal North Atlantic,” was published online August 8, 2016, in the journal Proceedings of the National Academy of Sciences.