Preventing malaria’s spread in Brazil
Efforts by Harvard T.H. Chan School of Public Health’s Marcia Castro to track the spread of malaria in Brazil and to prevent future cases were highlighted in a Sept. 1 Monga Bay article.
The article cited a 2025 study led by Castro, Andelot Professor of Demography and chair of the Department of Global Health and Population, that found a link between illegal gold mining and an uptick in malaria cases in the Yanomami Indigenous Territory in Brazil.
For the study, Castro and her colleagues looked at malaria cases reported in the entire Brazilian Amazon from 2003 to 2023, and in Yanomami Indigenous Lands from 2010-23. They also analyzed mining, deforestation, and climate data.
The researchers found that a 1% increase in the mined area in the Yanomami territory was linked with a 24% increase in monthly malaria cases. In addition, they found that even without increased mining activity, malaria cases still rose in areas that included routes used by the illegal miners, known as “garimpeiros.” These miners’ activities surged in Yanomami territory due to policies issued under the leadership of former Brazilian president Jair Bolsonaro, who served from January 2019 to January 2023, the Monga Bay articled noted.
“The garimpeiros move around a lot because they have to bring in supplies and machinery,” Castro told Mongabay. “When you pass through these areas, you’re a carrier of the parasite as you walk, and you can get bitten by a mosquito along the way. And just like that, [the disease] spreads.”
Castro and her colleagues are currently working to create an alert system to warn local Brazilian health authorities at the earliest sign of a malaria outbreak.
“We’ll be able to reach out to the coordinator of the [malaria] control program in that area and say, ‘Look, these are the places where there might be an increase’,” Castro said in the article.
Read the Monga Bay article:
Scientists use mining data to build malaria alert system in the Amazon
Learn more:
Malaria is gaining ground—but researchers are developing promising new solutions (Harvard Chan School news)
Tackling malaria in Brazil (Harvard Chan School news)
