Researchers warn of malaria spread in the highlands due to rising temperatures
Around 300 million people develop malaria every year. For babies and toddlers in particular, the infectious disease transmitted by the female Anopheles mosquito can quickly become fatal without treatment. According to the WHO World Malaria Report, around half a million children die of malaria each year.
Because the vector mosquitoes need high temperatures to reproduce, the disease is particularly common in Africa, South America and Southeast Asia. Researchers recently found that the tropical disease will spread even further in the future. Until now, people were protected due to the lower temperatures in the highlands. However, global warming is causing malaria to spread to higher areas, the researchers report.
People are affected by malaria in the highlands as well. Global warming could result in serious spread of malaria. This is what Mercedes Pascual from the University of Michigan and her team report in the science magazine. For example, warmer years were associated with a more frequent occurrence of the disease in the higher regions of Ethiopia and Colombia.
The researchers analyzed the changes in temperatures and malaria infections over a period of more than ten years in high-lying villages. Data from 1990 to 2005 were evaluated for 124 municipalities in the Antioquia region in western Colombia and from 1993 to 2005 for 159 municipalities around Debre Zeyit in Ethiopia. "Malaria climbs more and more when a year is warmer," Pascual reports. "If the temperatures in the affected regions rise by even a degree, there could be hundreds of thousands more malaria infections on both continents than previously expected." according to the researchers.
Dozens of millions of people live in the high areas that were previously considered malaria-free. Now the disease could spread rapidly there as well. Temperatures are lower in the highlands, so that the mosquitoes are difficult to reproduce and therefore can hardly infect humans. The Plasmodium vivax pathogen can no longer multiply at temperatures below 15 degrees Celsius. "The parasite is practically a race over time because its development is slower and slower in the cold," said Pascual.
Researchers call for sustainable measures to contain malaria in the highlands "Our latest studies show that as global warming progresses, malaria will also reach the mountains and spread to new heights. And because this population has no protective immune response, it will be particularly susceptible to disease and high mortality rates, ”said Menno Bouma, co-author of the study. The researchers are calling for the expansion of strategies to contain the disease. "Our results underline the magnitude of the problem and emphasize the need for sustainable interventions in these regions, especially in Africa," explains Pascual.
The study is the "first hard evidence" that malaria occurs in warmer years even at high altitudes that have not previously been affected. In colder years, the tropical disease only spreads to deeper areas, wrote the University of Michigan in a statement. ( ag)
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