It’s common knowledge by now that the Earth’s fish are going extinct, but there’s new research this week that warns whatever shellfish do survive may all end up being poisonous anyway. Warmer water is apparently much more hospitable for a nasty bacteria known as vibrio that causes several potentially deadly illnesses, like cholera. In this study, researchers say they’ve recorded a “doubling, tripling — in some cases quadrupling” of vibrio between 1958 and 2011. One of the lead authors of the study, which was just published in the Proceedings of the National Academy of Sciences, notes somewhat alarmingly: “This would represent a direct impact on human health that I think is kind of surprising.”
Vibrio is found in shellfish other than oysters, but the bacteria’s presence is one of the reasons for the R-month rule (“Only eat oysters during months with an R”). The bacteria proliferate in warm temperatures and love brackish water, so oysters in the area end up getting a buffet of toxins during the summer. And vibriosis is not a fun disease: The CDC says that in 2014, 27 percent of people infected with vibrio had to be hospitalized, and 4 percent died — a number the agency believes is an underestimate.
The study’s findings are based on bacteria levels found in 133 samples in nine parts of the North Atlantic. The researchers say they directly correlate with rising water temperatures, which means global warming is effectively delivering a double whammy: Not only are fast-rising temperatures forcing lobster, cod, and other fish to move north, the fish that remain may now present a health risk.