Ongoing global climate changes are likely to increase the problems of malaria in highland areas of Africa, Asia and South America. However, it is not clear that the total spread will lead to more people being affected. This according to a study from Umeå University that was published in the PNAS journal.
The existence of malaria is determined by different climate factors, which affect the area of distribution for malaria mosquitoes, but also the length of the season when mosquitoes are active. Joacim Rocklöv, senior lecturer at the Department of Public Health and Clinical Medicine, has, in an international study, compared five different models to predict the future transmission of malaria linked to climate. The study has looked at the expected incidence of malaria during the 2030s, 2050s and 2080s as well as studying how climate change will affect the incidence of malaria in the population in different areas, and how much longer the period of infection is every season.
According to the study, the different models agree that the problems of malaria will increase in the tropical highlands of Africa, South America and Southeast Asia. One reason that transmission and the effects of climate strike mostly in tropical regions is that they are poorer and frequently lack well-functioning healthcare systems. At the same time the study shows that there were differences in the assessments for other regions of the world and that there were also differences in the assessments of how the expansion of the different risk areas will appear.
“All in all this means that even if the problems of malaria will increase in populations in tropical highlands in different places on earth, in all likelihood other areas will not be affected as much. Meaning the problem is likely to be relatively stable from an overall perspective. However, this is controlled by factors other than climate, for example, that the population is relatively small or declining in regions where the malaria mosquito has an extended area of distribution, etc,” says Joacim Rocklöv.
The study has been conducted in The Inter-Sectoral Impact Model Intercomparison Project, which is to provide a basis for the new UN report on the impact and adaptation to changes in climate, which is to be presented later in the spring.