Ethiopia’s highlands traditionally have a built-in protection for the people who live there. The elevation and the cool temperatures have meant that malaria, the deadly mosquito-borne illness, cannot be transmitted.
But climate change may be putting an end to that safeguard. A new study led by a researcher at the University of Maine found that since 1981, the elevation needed to protect people from malaria has risen by 100 meters.
For the first time, people living in Ethiopia’s highlands could be vulnerable to the disease.
“What’s happening is the conditions, at least in terms of temperature, that are suitable for malaria are slowly creeping up at higher elevations,” said Bradfield Lyon at Maine's Climate Change Institute and School of Earth and Climate Sciences. “The same thing would be true in other highland locations throughout the tropics.”
"It's sort of eroding this natural buffer," he said.
The two most common types of parasites that cause malaria in the region require consistent temperatures above 18 degrees Celsius and 15 degrees Celsius respectively.
Lyon’s study found that temperatures in the Horn of Africa are rising by an average of 0.2 degrees Celsius per decade due to climate change. He said this may not sound like a major change, but that over the course of the years studied (1981 to 2014), more than 6 million people who once lived areas protected from malaria may have lost that protection.
Ethiopia’s capital Addis Ababa, at 2,300 meters above sea level, still sits well above the threshold for malaria. Lyon said the communities potentially at risk are at elevations between 1,200 and 1,700 meters.
Still, he emphasized that this is simply a meteorological study. He has not seen evidence that people in the described areas actually contracted malaria. But the research is pointing out that it is possible.
“It does not mean that these people, therefore, are going to get malaria. It just says that it is slowly enhancing the risk if we leave all other factors alone,” Lyon said. “I mean the hope is through interventions and so forth that we can, in fact, eradicate malaria in this and other regions of the tropics.”
In 2015, about 212 million people worldwide fell ill with malaria and about 429,000 died, according to the World Health Organization. About nine-tenths of the cases and deaths occurred in sub-Saharan Africa.
Worldwide, about 214 million people fall ill with malaria each year and 438,000 people die as a result, according to the Centers for Disease Control and Prevention. The most vulnerable are children living in sub-Saharan Africa.