Silva Guilherme Gonzaga da, Lopez Vinicius Marques, Vilarinho Ana Carolina, Datto-Liberato Felipe H, Oliveira Carlo José Freire, Poulin Robert, Guillermo-Ferreira Rhainer
Lestes Laboratory, Center of Entomology and Experimental Biology, Federal University of Triangulo Mineiro - UFTM, Uberaba, MG, Brazil; Federal University of Sao Carlos - UFSCar, São Carlos, SP, Brazil.
Lestes Laboratory, Center of Entomology and Experimental Biology, Federal University of Triangulo Mineiro - UFTM, Uberaba, MG, Brazil; Graduate Program in Entomology, University of Sao Paulo - USP, Ribeirão Preto, SP, Brazil.
Int J Parasitol. 2024 Mar;54(3-4):139-145. doi: 10.1016/j.ijpara.2023.10.002. Epub 2023 Nov 7.
Vector species richness may drive the prevalence of vector-borne diseases by influencing pathogen transmission rates. The dilution effect hypothesis predicts that higher biodiversity reduces disease prevalence, but with inconclusive evidence. In contrast, the amplification effect hypothesis suggests that higher vector diversity may result in greater disease transmission by increasing and diversifying the transmission pathways. The relationship between vector diversity and pathogen transmission remains unclear and requires further study. Chagas disease is a vector-borne disease most prevalent in Brazil and transmitted by multiple species of insect vectors of the subfamily Triatominae, yet the drivers of spatial variation in its impact on human populations remain unresolved. We tested whether triatomine species richness, latitude, bioclimatic variables, human host population density, and socioeconomic variables predict Chagas disease mortality rates across over 5000 spatial grid cells covering all of Brazil. Results show that species richness of triatomine vectors is a good predictor of mortality rates caused by Chagas disease, which supports the amplification effect hypothesis. Vector richness and the impact of Chagas disease may also be driven by latitudinal components of climate and human socioeconomic factors. We provide evidence that vector diversity is a strong predictor of disease prevalence and give support to the amplification effect hypothesis.
媒介物种丰富度可能通过影响病原体传播率来推动媒介传播疾病的流行。稀释效应假说预测，更高的生物多样性会降低疾病流行率，但证据尚无定论。相比之下，放大效应假说表明，更高的媒介多样性可能通过增加和多样化传播途径导致更大的疾病传播。媒介多样性与病原体传播之间的关系仍不明确，需要进一步研究。恰加斯病是一种在巴西最为流行的媒介传播疾病，由锥蝽亚科的多种昆虫媒介传播，但对其对人类种群影响的空间变异驱动因素仍未得到解决。我们测试了锥蝽物种丰富度、纬度、生物气候变量、人类宿主种群密度和社会经济变量是否能预测覆盖巴西全境的5000多个空间网格单元中的恰加斯病死亡率。结果表明，锥蝽媒介的物种丰富度是恰加斯病所致死亡率的良好预测指标，这支持了放大效应假说。媒介丰富度和恰加斯病的影响也可能受气候和人类社会经济因素的纬度成分驱动。我们提供的证据表明，媒介多样性是疾病流行率的有力预测指标，并支持放大效应假说。
