How climate change is spreading malaria in Africa

Disease-transmitting mosquitoes have dramatically expanded their range over the past century as temperatures warmed, the scientists reported.< /p>

Warming temperatures are driving animals and plants to new habitats, sometimes with devastating consequences for ecosystems. But there is little evidence regarding how far and how fast the invaders might move.

A new study offers a glimpse into the future looking forward pass. Mosquitoes that transmit malaria in sub-Saharan Africa have moved to higher altitudes by about 6.5 meters (about 21 feet) per year and away from the equator by 4.7 kilometers (about three miles) per year at the over the past century, according to the study.

This rate is consistent with climate change and may explain why the extent of malaria has expanded in recent decades, the authors said. The findings have serious implications for countries that are unprepared to deal with the disease.

"If it was random, and if it wasn't not climate-related, it wouldn't look like it was properly climate-related," said Colin Carlson, a biologist at Georgetown University's Center for Global Health Science and Security and lead author of the paper. study was published Tuesday in the journal Biology Letters.

Most studies of the impact of climate change on health tend to focus on the spread of disease , which can be tricky to trace back to a single cause - and be predictive.The new study is more of a retrospective look at how mosquitoes got around.

"It's really consistent with where and how transmission is actually happening in those places," said Sadie Ryan, a medical geographer at the Unive rsity of Florida.

The displacement rate confirms experts' worst fears about the impact of climate change on infectious diseases, Dr Ryan added.

"What we expect is quite dramatic - and it looks quite dramatic," she said. "The fact that it actually does what we anticipate and fear to happen is very compelling."

As the planet warms, plants and animals , especially invertebrates, seek cooler temperatures. temperatures, either moving to higher altitudes or approaching the poles. A meta-analysis estimated that to date, terrestrial species have moved at a rate of 1.1 meters (3.6 feet) per year and poleward at a rate of 1.7 kilometers (1.1 mile) per year.

< p class="css-at9mc1 evys1bk0">Ticks that transmit Lyme disease, for example, are greatly expanding their range in the northern United States. Bats are also on the move, and with them the diseases they transmit, such as rabies.

In the Northeast, lobsters are dying of a fungal disease linked to warming, and fish migrate north or to deeper waters in search of cooler temperatures. This leaves seabirds like puffins with a dwindling food supply and forces commercial fishing to turn to new types of catches. it's usually getting warmer, and we don't often think about the largely interconnected world we live in,” said Morgan Tingley, an ecologist at the University of California, Los Angeles.

In Hawaii, the invasion of new species of mosquitoes threaten two bird species threatened by avian malaria: the 'akeke'e and the 'akikiki. There are less than 1,000 'akeke'es and less than 50 'akikikis; the latter have declined precipitously in recent years and are expected to disappear this decade, Dr Tingley said.

He and other researchers have stressed the importance of collecting data to understand exactly how and at what speed mosquitoes and other disease vectors move around the world. Warmer climates should benefit mosquitoes, as they and the parasites they carry reproduce more rapidly at higher temperatures.

"We live in a world where it's 1.2 degrees warmer, and we have...