Brunner J L, Schock D M, Collins J P
School of Life Sciences, Arizona State University, Tempe, Arizona 85287-4501, USA.
Dis Aquat Organ. 2007 Sep 14;77(2):87-95. doi: 10.3354/dao01845.
Transmission is central to pathogen fitness and strongly influences the impact of pathogens on host populations. Particularly important to transmission dynamics is the distinction between direct transmission requiring close physical contact (e.g. bumping, fighting, or coughing) and indirect transmission from environmental sources such as contaminated substrates. We present data from 4 experiments addressing the form, routes, and timing of transmission of Ambystoma tigrinum virus (ATV) among tiger salamanders Ambystoma tigrinum nebulosum. Our data suggest that ATV is efficiently transmitted by direct interactions between live animals (bumping, biting and cannibalism) as well as by necrophagy and indirectly via water and fomites. Determining which form of transmission is most important in nature is essential for understanding transmission at the population level. Our experiments also revealed an important temporal aspect of infectiousness: larval salamanders become infectious soon after exposure to ATV and their propensity to infect others increases with time. These results begin to clarify the mechanisms and dynamics of ATV transmission and lead to key questions that need to be addressed in future research.
传播对于病原体的适应性至关重要，并强烈影响病原体对宿主种群的影响。对于传播动态而言，特别重要的是区分需要密切身体接触的直接传播（例如碰撞、打斗或咳嗽）和来自受污染基质等环境源的间接传播。我们展示了来自4个实验的数据，这些实验涉及虎纹钝口螈病毒（ATV）在虎螈Ambystoma tigrinum nebulosum之间的传播形式、途径和时间。我们的数据表明，ATV可通过活体动物之间的直接相互作用（碰撞、撕咬和同类相食）以及食尸行为有效传播，也可通过水和污染物间接传播。确定哪种传播形式在自然环境中最为重要，对于理解种群水平的传播至关重要。我们的实验还揭示了传染性的一个重要时间方面：幼体蝾螈在接触ATV后不久就具有传染性，并且它们感染其他个体的倾向会随着时间增加。这些结果开始阐明ATV传播的机制和动态，并引出了未来研究中需要解决的关键问题。
