Plowright Raina K, Manlove Kezia R, Besser Thomas E, Páez David J, Andrews Kimberly R, Matthews Patrick E, Waits Lisette P, Hudson Peter J, Cassirer E Frances
Department of Microbiology and Immunology, Montana State University, 109 Lewis Hall, Bozeman, MT, 59717, USA.
Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, 99164, USA.
Ecol Lett. 2017 Oct;20(10):1325-1336. doi: 10.1111/ele.12829. Epub 2017 Sep 4.
Superspreading, the phenomenon where a small proportion of individuals contribute disproportionately to new infections, has profound effects on disease dynamics. Superspreading can arise through variation in contacts, infectiousness or infectious periods. The latter has received little attention, yet it drives the dynamics of many diseases of critical public health, livestock health and conservation concern. Here, we present rare evidence of variation in infectious periods underlying a superspreading phenomenon in a free-ranging wildlife system. We detected persistent infections of Mycoplasma ovipneumoniae, the primary causative agent of pneumonia in bighorn sheep (Ovis canadensis), in a small number of older individuals that were homozygous at an immunologically relevant genetic locus. Interactions among age-structure, genetic composition and infectious periods may drive feedbacks in disease dynamics that determine the magnitude of population response to infection. Accordingly, variation in initial conditions may explain divergent population responses to infection that range from recovery to catastrophic decline and extirpation.
超级传播，即一小部分个体对新感染的贡献不成比例的现象，对疾病动态有着深远影响。超级传播可通过接触、传染性或传染期的差异而出现。后者很少受到关注，但它驱动着许多关乎公共卫生、家畜健康和保护的重大疾病的动态变化。在此，我们展示了在一个自由放养的野生动物系统中，超级传播现象背后传染期存在差异的罕见证据。我们在一小部分年龄较大且在一个免疫相关基因位点纯合的个体中检测到了绵羊肺炎支原体（大角羊肺炎的主要病原体）的持续感染。年龄结构、基因组成和传染期之间的相互作用可能会驱动疾病动态中的反馈，从而决定种群对感染的反应程度。因此，初始条件的差异可能解释了种群对感染的不同反应，这些反应范围从恢复到灾难性衰退和灭绝。
