Host density and habitat structure influence host contact rates and Batrachochytrium salamandrivorans transmission
Host density and habitat structure influence host contact rates and Batrachochytrium salamandrivorans transmission
复制标题
DOI：
10.1038/s41598-020-62351-x
复制
发表时间：
2020-03-27
影响因子：
4.6
通讯作者：
Gray, Matthew J.
中科院分区：
文献类型：
--
作者：
Malagon, Daniel A.;Melara, Luis A.;Gray, Matthew J.
Batrachochytrium salamandrivorans（Bsal）是一种对蝾螈具有高致病性的入侵性病原菌。在这个系统中建模感染动态可以促进积极主动的努力，以减轻这种病原体对北美物种的影响。鉴于其广泛的分布和高丰度，东部蝾螈（Notophthalmus viridescens）有可能显着影响Bsal流行病学。我们设计的实验是：1）估计不同宿主密度和栖息地结构下的接触率; 2）估计从感染者到易感者的传播概率。使用这些实验中产生的数据的参数估计，我们使用微分方程系统为蝾螈种群建模感染和疾病结果。我们发现，主机接触率是密度依赖性的，并增加栖息地结构减少接触。即使在感染的早期阶段，蝾螈之间接触Bsal传播的可能性也非常高（>90%）。我们的模拟显示Bsal在病原体引入后在个体之间快速传播，感染流行率在一个月内超过90%，蝾螈在三个月内死亡率>80%。在复杂生境和简单生境中，东方蝾螈的Bsal基本繁殖率（R-0）分别为1.9和3.2。虽然降低宿主密度和增加栖息地的复杂性可能会减少传播，这些管理策略可能是无效的，在阻止Bsal入侵东部蝾螈种群，由于这个物种的超易感性。
Batrachochytrium salamandrivorans (Bsal) is an emerging invasive pathogen that is highly pathogenic to salamander species. Modeling infection dynamics in this system can facilitate proactive efforts to mitigate this pathogen's impact on North American species. Given its widespread distribution and high abundance, the eastern newt (Notophthalmus viridescens) has the potential to significantly influence Bsal epidemiology. We designed experiments to 1) estimate contact rates given different host densities and habitat structure and 2) estimate the probability of transmission from infected to susceptible individuals. Using parameter estimates from data generated during these experiments, we modeled infection and disease outcomes for a population of newts using a system of differential equations. We found that host contact rates were density-dependent, and that adding habitat structure reduced contacts. The probability of Bsal transmission given contact between newts was very high (>90%) even at early stages of infection. Our simulations show rapid transmission of Bsal among individuals following pathogen introduction, with infection prevalence exceeding 90% within one month and >80% mortality of newts in three months. Estimates of basic reproductive rate (R-0) of Bsal for eastern newts were 1.9 and 3.2 for complex and simple habitats, respectively. Although reducing host density and increasing habitat complexity might decrease transmission, these management strategies may be ineffective at stopping Bsal invasion in eastern newt populations due to this species' hyper-susceptibility.