Malaria is increasing in Indigenous and artisanal mining areas in the Brazilian Amazon

In 2015, Brazil received the Malaria Champions of the Americas Award from the Pan American Health Organization. That same year, the National Malaria Control Program (NMCP) launched a plan to eliminate Plasmodium falciparum¹. One year later, Brazil recorded the lowest number of malaria cases in 37 years (about 143,000), 99.9% of which were in the Amazon region. This trend suffered a setback in 2017, when around 231,000 cases were reported. Although no single reason explains the increase, Brazil was facing an economic crisis, austerity measures imposed limits on health spending, and other emergencies such as Zika virus and Chikungunya virus shifted the focus away from malaria². In 2019, when President Bolsonaro started his four-year term, major changes in the Ministry of Health affected malaria control. The NMCP was merged into a division that also oversaw 35 neglected diseases, all technical advisory groups were eliminated and there was no support to develop a strategic plan for malaria elimination. Despite this unfavorable situation, in 2022 Brazil launched an elimination plan to achieve zero malaria in four phases: first, reduce cases to <68,000 by 2025; second, eliminate P. falciparum malaria and deaths due to malaria by 2030; third, achieve zero cases and deaths by 2035; and fourth, prevent the reintroduction of malaria from 2035 onward³.

The number of malaria cases is again declining (31% lower in 2021 than in 2017), but this trend is not homogeneous across the country (Fig. 1c). In Mato Grosso and Roraima, cases increased by 727% and 110%, respectively, between 2017 and 2021. In addition, the distribution of cases by the locality (a small geographical unit used by the NMCP) where the infection originated has changed since 2017 (Fig. 1c). Cases in urban, rural and settlement localities have declined since 2017, but those in artisanal mining and Indigenous localities have increased by 257% and 62%, respectively. This shift in the distribution of cases by locality does not result from a failure in the NMCP’s activities. It is a consequence of the dismantling of environmental agencies and changes in environmental legislation implemented during the government of President Bolsonaro, which relaxed environmental protection and violated Indigenous rights. Those changes increased illegal deforestation and artisanal mining, which are major drivers of malaria transmission in the Amazon. Between 2019 and 2022, 45,568 km² of forest were removed (an area larger than the size of Rio de Janeiro state); 2021 witnessed 13,038 km² of deforestation, the highest annual rate since 2006. Much of this deforestation and mining occurred in Indigenous lands. In 2021, the area of artisanal mining in Indigenous lands was 102.5% higher than in 2018 and represented 11% of all artisanal mining areas in the Amazon.

Fig. 1: Protected areas, airstrips and malaria in the Brazilian Amazon.

a, Locations of Indigenous lands, conservation units and airstrips, highlighting those that are within 5 km of a mining area. Airstrips outside the map boundaries were included because they may directly affect areas in the Amazon. b, Annual parasite index (API) in 2021, calculated as confirmed malaria cases per 1,000 people. Municipalities in white reported no locally acquired cases. API categories: very low risk, API < 1; low risk, 1 ≥ API < 10; medium risk, 10 ≥ API < 50; high risk, API ≥ 50. c, Percentage distributions of confirmed malaria cases by type of locality (mining, Indigenous, urban, rural and settlement) and the total number of cases reported between 2003 and 2022. Data for 2022 are preliminary and thus subject to change. A locality is a small geographical area used by the NMCP — a municipality is divided into several localities. The primary y axis shows percentages and is the same for all graphs. The secondary y axis shows the number of cases, with different scales for each state.

Deforestation and artisanal mining also contribute to other problems: an increase in respiratory conditions as PM_2.5 particles are emitted from forest fires; malnutrition due to contamination of water and food with mercury used in artisanal mining; infectious and neurological diseases associated with mercury poisoning; and violence, especially homicide and rape. All of these effects are now impacting the Yanomami people, who are facing severe malnutrition, the worst ever reported among Indigenous communities in the Americas, with malaria also widespread⁴ (Fig. 1b). The Yanomami Indigenous land is the largest in Brazil, spans two states (Roraima and Amazonas) and borders Venezuela. It also contains the third-largest area of artisanal mining in Indigenous lands and the largest number of airstrips (75), 34% of which are within 5 km of a mining area, according to Mapbiomas (https://mapbiomas.org/) (Fig. 1a). Despite several reports and alerts sent to the Federal Prosecutor’s Office, the National Indigenous People Foundation (Funai) and the Army, it would appear that President Bolsonaro did not take action to prevent what now became a humanitarian crisis⁵.

The consequences of inaction and environmental destruction are a threat to malaria elimination. In Roraima, malaria cases reported in artisanal mining and Indigenous localities increased by 65,166.7% and 410.8% between 2017 and 2021, respectively. In Amazonas, those figures were 84.4% and 7.5%. In 2021, 46.5% of all malaria cases within Indigenous localities in Brazil, and 30.5% of those in artisanal mining localities, originated in municipalities that include Yanomami territory. Although 2022 data are preliminary, malaria cases in artisanal mining localities in Roraima correspond to 55% of cases so far reported in the state (an 84% increase from the previous year). In 2021, 91.9% of all artisanal mining areas in the Amazon were in the states of Pará and Mato Grosso. Between 2017 and 2021, malaria cases in Indigenous and artisanal mining localities increased by 152.5% and 217.1% in Pará, respectively. In Mato Grosso those figures were 5,022.2% and 30,221.43% (Fig. 1c). Mining is associated with high mobility of people, which increases malaria transmission⁶. In Brazil, 95.3% of cases in Indigenous localities were locally acquired and only 4.7% were imported in 2021, but in artisanal mining localities, 53.2% of the cases were imported. Considering the municipalities that include Yanomami lands, 95.5% of cases in Indigenous localities were locally acquired, and 93.4% of those in artisanal mining areas were imported.

Under this scenario, eliminating malaria in Brazil will demand both health and environmental interventions. Current NMCP efforts, despite the challenges of the past four years, have contributed to a decline of malaria in some localities but have not mitigated transmission in Indigenous and mining localities. Four priority issues are critical to put Brazil on the path to malaria elimination. First, revoke legislation that facilitated deforestation and mining expansion, and remove mining activities from Indigenous lands (this has started in the Yanomami land, but must be extended to the rest of the Amazon). Second, strengthen malaria surveillance so that it becomes a core intervention, as proposed in the third pillar of the Global Technical Strategy for Malaria 2016–2030⁷; the network of community health agents can become a powerful tool to support rapid diagnosis, proper treatment and monitoring of case importation. Third, immediately target critical areas, as the top 10 municipalities in cases reported in Indigenous localities account for 72.9% of all cases in those localities, while the top 10 in artisanal mining localities account for 93.4%. Finally, incorporate deforestation alerts into NMCP routine surveillance, data analytics and response activities.

President Lula da Silva, having taken office in January 2023, now has a unique window of opportunity to put Brazil on the path to malaria elimination, and at the same time send a message and become an inspiration to other countries that include parts of the Amazon and aim to eliminate malaria. Whether Brazil will move toward elimination or not depends on governmental support, NMCP’s actions, environmental conservation actions and respect for Indigenous rights. The Amazon, and the Indigenous people, cannot wait any longer⁸.