Deforestation causes malaria

Amazon studies link malaria to deforestation

Both studies found that deforestation increases the risk of malaria
transmission
Luisa Massarani and Mike Shanahan
30 January 2006
Source: SciDev.Net

[RIO DE JANEIRO] Two studies in the Amazon rainforest have shown a link
between deforestation and an increased risk of malaria. The findings
have implications for health management and environmental policy in the
region.

According to research published today (30 January), the clearing of
trees in Brazil's Amazon region to create new settlements increases the
short-term risk of malaria by creating areas of standing water in which
mosquitoes can lay their eggs.

The study, in Proceedings of the National Academy of Sciences, also
found that once agriculture and urban development are established in
frontier regions, this habitat declines and malaria transmission rates fall.

"Malaria mitigation strategies for frontier settlements require a
combination of preventive and curative methods and close collaboration
between the health and agricultural sectors," say the team led by Marcia
Caldas de Castro of the University of South Carolina, United States.

The study comes less than a month after one in neighbouring Peru showed
that malaria epidemics in the Amazon were linked to deforestation. The
findings appeared in January's issue of the American Journal of
Tropical Medicine and Hygiene.

The study showed that the biting rate of Anopheles darlingi, the
Amazon's main malaria-spreading mosquito, was nearly 300 times greater in
cleared areas than forested ones.

"Most people think malaria is on the rise simply because the mosquito
feeds on the increasing numbers of humans in the rainforest. But our
results show that altering the landscape likely plays an even larger role
than people moving into the jungle", says lead researcher Jonathan
Patz, of the University of Wisconsin-Madison, United States.

Patz says the fact that deforestation may affect the prevalence of a
disease like malaria raises some larger issues.

"I feel conservation policy is one and the same with public health
policy. It's probable that protected conservation areas may ultimately be
an important tool in our disease prevention strategies," he says.