Scientists are speculating that climate change could re-introduce cholera to North America.
The theory goes that if climate change brings on extreme rainstorms – like those in Southern California last fall, or in Milwaukee last July – water treatment plants could be overwhelmed.
And it was the advent of water purification in the 19th century that wiped out the disease in North America.
“Perhaps if we have a breakdown in sewage treatment plants with severe weather patterns, (this could) then bring us to a risk of cholera, which we haven’t had for over a hundred years,” Rita Colwell, a public health professor at the University of Maryland and Johns Hopkins University, said at a Canadian Water Network meeting in Ottawa this week, as reported by CBC News.
Other scientists agreed, but some wondered whether the threat was not more immediate.
“Drinking water – providing it safely, is a complex knowledge-based business and it’s getting more complicated all the time,” said Steve Hrudey, a University of Albert public health engineer, told CBC News. “If you’re in a community of 100, it’s unlikely that you’re a full-time water operator. You’re probably responsible for snow removal and garbage removal and a few other things. What’s the likelihood that you’re going to be able to give the kind of attention to drinking water safety that it deserves?”
A handful of recent studies indicate that climate change may already be affecting cholera outbreaks.
For instance, in 2009, Spanish researchers showed that an increase in cholera cases in Zambia was associated with changing climate patterns. That same year, Papua New Guinea reported its first case of cholera in more than 50 years. That year happened to be an El Nino year, and scientists believe they are correlated.