Intermediate forest cover and malaria risk in an Amazon deforestation frontier

Autor(es)

Laporta, Gabriel Z. ; Valle, Denis ; Prist, Paula R. ; Ilacqua, Roberto C. ; Santos, Thais C. ; Madeira, Fernanda P. ; Silva, Glauco M. ; Brilhante, Andreia F. ; Nolan, Melissa S. ; Speranca, Marcia A.

• Tipo de documento: Artigo Científico
• Fonte: Acta Tropica; v. 269, p. 8-pg., 2025-09-01.

Resumo

Malaria exposure risk, measured by anopheline infection rates, appears highest in Amazonian landscapes with approximately 50 % remaining forest cover, a common condition across the region. However, the effects of landscape configuration on the density of infected vectors and human malaria incidence remain poorly understood. A pilot natural experiment was carried out across 40 sites in a deforestation frontier in Acre state, Brazilian Amazon, where malaria is endemic. Sites were selected to represent a gradient of forest cover and deforestation levels under controlled conditions. We collected data on mosquito vectors (abundance and infection rates) and human malaria infections to assess how landscape structure influences transmission. Sites with intermediate forest cover, often associated with high fragmentation, exhibited higher Nyssorhynchus mosquito abundance and greater anopheline infection rates, leading to increased risk of Plasmodium vivax and P. falciparum infections. All human infections detected were asymptomatic (n = 16), representing a persistent reservoir for transmission and a major obstacle to malaria elimination. Our findings suggest that malaria transmission may persist where intermediate forest cover dominates, even with antimalarial drug-based interventions. Elimination strategies should integrate radical cure treatments with alternative vector control approaches, especially for outdoor-biting Nyssorhynchus anophelines. Depending on the amount of existing forest cover, landscape-based strategies (forest conservation/restoration payments) may help naturally regulate vector populations and support both malaria elimination and Amazon rainforest preservation. (AU)

• Processo FAPESP: 21/06669-6 - Coorte de paisagens zoonóticas sob efeito de desmatamento e mudanças no uso da terra na Amazônia
• Beneficiário: Gabriel Zorello Laporta
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores - Fase 2
• Processo FAPESP: 22/10392-2 - Eco-epidemiologia de doenças infecciosas em paisagens da Região Amazônica sob efeito de desmatamento: implicações na saúde única
• Beneficiário: Marcia Aparecida Speranca
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 23/08053-8 - Estimativas de perdas florestais com sensoriamento remoto e drone multiespectral em paisagens zoonóticas sob efeito de desmatamento na Amazônia
• Beneficiário: Roberto Cardoso Ilacqua
• Modalidade de apoio: Bolsas no Brasil - Doutorado