As if we needed further proof that chopping down the Amazon was a bad idea, a new study suggests that deforestation in Brazil had led to an increased incidence of disease.
Writing in the current (June 16, 2010) online issue of the CDC journal Emerging Infectious Diseases, a team of scientists from the University of Wisconsin-Madison found that clearing tropical forest increases incidence of malaria by nearly 50 percent.
The report combined data on the prevalence of malaria in the Brazilian Amazon near Peru with satellite imagery that showed the extent of logging in the forest. Deforestation need not be widespread to sicken local populations: a 4 percent change in forest cover was associated with a 48 percent increase in malaria incidence in the surrounding area.
The researchers say that clearing of tropical forests creates conditions that favor malaria’s primary carrier in the Amazon, the mosquito Anopheles darlingi, which transmits the malaria parasite.
For years, Scientists have struggled to predict precisely how climate change will change disease patterns in the coming century. The U.S. Environment Protection Agency notes that climate change “may increase the risk of some infectious diseases, particularly…those spread by mosquitoes and other insects”, but also conceded that “given the complexity of factors that influence human health, assessing health impacts related to climate change poses a difficult challenge.”
But this new study provides evidence of how environmental degradation–in the form of unsustainable land-use practices–is affecting human health today. And there is a convergence with future climate change. The logging and burning of tropical rainforests accounts for around 15% of global carbon emissions, and eliminates important carbon sinks.
A study in last year’s Science, covered by TIME, showed how the economic boost of deforestation in the Amazon—the most prevalent argument for chopping down trees– is short-lived. But by showing how it might sicken as well as impoverish local populations, this new health study provides further evidence that felling forests for short-term profit is very short sighted.
The study also boosts the urgency for an international anti-deforestation plan. At the Copenhagen summit, a plan titled Reduced Emissions from Deforestation and Degradation (REDD) laid out how wealthier nations could pay rainforest countries for preserving their trees. The lack of a wider agreement limited the progress that could be made on REDD, but the Copenhagen Accord does include a mention of it. To those concerned about environmental justice, climate change and human health, this new study provides further evidence that saving the rainforest should be of the highest priority in any future climate change talks.