University of Florida, Florida Medical Entomology Laboratory, Vero Beach, FL, USA.
University of Florida, Wildlife Ecology and Conservation, Gainesville, FL, USA.
Commun Biol. 2021 Jun 28;4(1):804. doi: 10.1038/s42003-021-02347-z.
The composition of wildlife communities can have strong effects on transmission of zoonotic vector-borne pathogens, with more diverse communities often supporting lower infection prevalence in vectors (dilution effect). The introduced Burmese python, Python bivittatus, is eliminating large and medium-sized mammals throughout southern Florida, USA, impacting local communities and the ecology of zoonotic pathogens. We investigated invasive predator-mediated impacts on ecology of Everglades virus (EVEV), a zoonotic pathogen endemic to Florida that circulates in mosquito-rodent cycle. Using binomial generalized linear mixed effects models of field data at areas of high and low python densities, we show that increasing diversity of dilution host (non-rodent mammals) is associated with decreasing blood meals on amplifying hosts (cotton rats), and that increasing cotton rat host use is associated with increasing EVEV infection in vector mosquitoes. The Burmese python has caused a dramatic decrease in mammal diversity in southern Florida, which has shifted vector host use towards EVEV amplifying hosts (rodents), resulting in an indirect increase in EVEV infection prevalence in vector mosquitoes, putatively elevating human transmission risk. Our results indicate that an invasive predator can impact wildlife communities in ways that indirectly affect human health, highlighting the need for conserving biological diversity and natural communities.
野生动物群落的组成可以对人畜共患病媒介传播病原体的传播产生强烈影响，通常群落多样性更高的情况下，媒介中的感染率较低（稀释效应）。引入的缅甸蟒蛇 Python bivittatus 正在美国佛罗里达州南部消灭大型和中型哺乳动物，对当地社区和人畜共患病病原体的生态产生影响。我们调查了入侵捕食者对佛罗里达州地方性人畜共患病病原体——沼泽埃博拉病毒（EVEV）生态的影响，该病毒在蚊子-啮齿动物循环中传播。我们使用高和低蟒蛇密度区域的现场数据的二项式广义线性混合效应模型，表明稀释宿主（非啮齿类哺乳动物）多样性的增加与扩增宿主（棉鼠）血液餐的减少有关，而棉鼠宿主利用率的增加与传播媒介蚊子中的 EVEV 感染增加有关。缅甸蟒蛇的引入导致佛罗里达州南部的哺乳动物多样性急剧减少，这导致了媒介宿主向 EVEV 扩增宿主（啮齿动物）的利用发生转变，从而间接增加了 EVEV 在媒介蚊子中的感染率，推测会增加人类传播的风险。我们的研究结果表明，入侵捕食者可以以间接影响人类健康的方式影响野生动物群落，突出了保护生物多样性和自然群落的必要性。
