All-time high: malaria spreading to new altitudes
A new study has suggested that warmer temperatures are causing malaria to spread to higher altitudes.
Published by the journal Science, researchers have established that people living in the highlands of South America and Africa are at a significantly higher risk of the disease during hotter years.
They believe higher temperatures could result in potentially millions more cases of the mosquito-borne illness. Higher altitude regions have previously proven a sanctuary from malaria.
A shift in conditions
Mosquitoes and the malaria parasite itself find it difficult to survive and flourish in cooler areas.
Previously, people who lived in regions of higher altitude were less at risk of contracting malaria, but the evidence now points to the disease penetrating regions that had historically been free of malaria.
The researchers looked at the densely populated regions of Columbia and Ethiopia’s highlands, both of which have comprehensive records of malaria cases from the 1990s to 2005. During warmer years, malaria travelled into the higher mountains but remained in the lower regions during cooler ones.
If global temperatures continue to rise, the Ethiopian highlands could be even more vulnerable.
A potentially worrying increase
Based on the distribution of malaria with altitude, the researchers also suggested a 1C rise in temperature could mean an extra three million cases of malaria in under 15-year-olds every year.
The researchers also concluded that people living in regions previously unaffected by malaria could be particularly vulnerable. They suggested a focus on borderline areas as the disease is easier to contain and control there, as opposed to lower altitude regions where it has already taken hold.
The World Health Organisation recently estimated that there were approximately 207 million cases of malaria in 2012, resulting in roughly 627,000 deaths, the majority of them African children.