Kozakiewicz Christopher P, Burridge Christopher P, Funk W Chris, Craft Meggan E, Crooks Kevin R, Fisher Robert N, Fountain-Jones Nicholas M, Jennings Megan K, Kraberger Simona J, Lee Justin S, Lyren Lisa M, Riley Seth P D, Serieys Laurel E K, VandeWoude Sue, Carver Scott
School of Natural Sciences University of Tasmania Hobart TAS Australia.
Department of Biology Colorado State University Fort Collins CO USA.
Evol Appl. 2020 Feb 20;13(8):1806-1817. doi: 10.1111/eva.12927. eCollection 2020 Sep.
Urban development has major impacts on connectivity among wildlife populations and is thus likely an important factor shaping pathogen transmission in wildlife. However, most investigations of wildlife diseases in urban areas focus on prevalence and infection risk rather than potential effects of urbanization on transmission itself. Feline immunodeficiency virus (FIV) is a directly transmitted retrovirus that infects many felid species and can be used as a model for studying pathogen transmission at landscape scales. We investigated phylogenetic relationships among FIV isolates sampled from five bobcat () populations in coastal southern California that appear isolated due to major highways and dense urban development. Divergence dates among FIV phylogenetic lineages in several cases reflected historical urban growth and construction of major highways. We found strong FIV phylogeographic structure among three host populations north-west of Los Angeles, largely coincident with host genetic structure. In contrast, relatively little FIV phylogeographic structure existed among two genetically distinct host populations south-east of Los Angeles. Rates of FIV transfer among host populations did not vary significantly, with the lack of phylogenetic structure south-east of Los Angeles unlikely to reflect frequent contemporary transmission among populations. Our results indicate that major barriers to host gene flow can also act as barriers to pathogen spread, suggesting potentially reduced susceptibility of fragmented populations to novel directly transmitted pathogens. Infrequent exchange of FIV among host populations suggests that populations would best be managed as distinct units in the event of a severe disease outbreak. Phylogeographic inference of pathogen transmission is useful for estimating the ability of geographic barriers to constrain disease spread and can provide insights into contemporary and historical drivers of host population connectivity.
城市发展对野生动物种群之间的连通性有重大影响，因此很可能是影响野生动物病原体传播的一个重要因素。然而，大多数对城市地区野生动物疾病的调查都集中在患病率和感染风险上，而不是城市化对传播本身的潜在影响。猫免疫缺陷病毒（FIV）是一种直接传播的逆转录病毒，可感染许多猫科动物物种，可作为研究景观尺度上病原体传播的模型。我们调查了从南加州沿海五个短尾猫种群中采集的FIV分离株之间的系统发育关系，这些种群由于主要高速公路和密集的城市发展而显得孤立。在几个案例中，FIV系统发育谱系之间的分歧日期反映了历史上的城市发展和主要高速公路的建设。我们在洛杉矶西北部的三个宿主种群中发现了很强的FIV系统地理结构，这在很大程度上与宿主的遗传结构一致。相比之下，在洛杉矶东南部两个遗传上不同的宿主种群中，FIV系统地理结构相对较少。宿主种群之间FIV的传播率没有显著差异，洛杉矶东南部缺乏系统发育结构不太可能反映种群之间频繁的当代传播。我们的结果表明，宿主基因流动的主要障碍也可以作为病原体传播的障碍，这表明碎片化种群对新型直接传播病原体的易感性可能降低。宿主种群之间FIV的交换不频繁表明，在严重疾病爆发时，最好将种群作为不同的单位进行管理。病原体传播的系统地理推断有助于估计地理障碍限制疾病传播的能力，并可以深入了解宿主种群连通性的当代和历史驱动因素。
