In 2010, an estimated 660,000 people died from malaria. (This number may be very low – the standard annual estimate is one million.) Malaria is spread by mosquitoes carrying a parasite. The parasite is injected into human bodies when mosquitoes bite them and suck their blood. Once inside the body, the parasite reproduces and spreads throughout, causing damage and often death. About 300 to 500 million people are affected by the disease each year. Many cases occur in children. Africa, the Americas, Asia, and the western Pacific are areas where malaria is most common.
A recent research study has identified a link between healthy forests and the potential for less transmission of malaria to humans. The basic explanation for less malaria in certain forested areas is that there are more wild mammals for mosquitoes to target for their blood meals. When they have a diversity of targets, they have less attention for biting humans, and therefore less of the malaria-causing parasites enter human bodies. Another aspect of healthy forest biodiversity is the presence of mosquitoes that do not spread malaria (non-vector mosquitoes). When there are many non-vector mosquitoes competing to bite the same number of wild mammals in a habitat, there will probably be fewer opportunities for malaria-causing mosquitoes to bite them.
The study authors also say humans living near wild areas where there may be an abundance of mosquitoes is probably not a good idea. In fact, clearing natural areas of plant life has been a way of decreasing mosquito populations and infective bites. However, there may also be good reason for maintaining biodiversity in certain areas to encourage the same outcomes.
As the researchers explained, ‘Contrary to what has long been believed, forest conservation and malaria control are not incompatible, and biodiversity issues should be included in the World Health Organization Malaria Eradication Research Agenda in order to achieve the desirable goals of biological conservation and maintenance of low malaria endemicity.’ (Source: PLOS)