Mycoplasma gallisepticum infection dynamics in a house finch population:: seasonal variation in survival, encounter and transmission rate
Mycoplasma gallisepticum infection dynamics in a house finch population:: seasonal variation in survival, encounter and transmission rate
复制标题
DOI：
10.1111/j.0021-8790.2004.00840.x
复制
发表时间：
2004-07-01
影响因子：
4.8
通讯作者：
Cooch, EG
中科院分区：
文献类型：
--
作者：
Faustino, CR;Jennelle, CS;Cooch, EG
1.我们认为，一个新出现的病原体（鸡毒支原体爱德华和Kanarek）的影响，在人口的一个新的主机（家雀，Carpodacus mexicanus穆勒）的明显的生存，遇到和过渡率。我们使用了一个多状态分析的标记遇到数据从单独标记的鸟类。个别鸟类被归类为一个特定的疾病“状态”，状态之间的转换率，条件是明显的生存，类似于新的感染率和感染后恢复。我们假设M。鸡毒败血症感染将减少受感染个体的表观存活率，并且这种减少的幅度将作为宿主生理条件的函数而变化（在我们的分析中，其特征在于包括人口统计学和环境替代物作为协变量）。我们发现一致支持的假设，M。鸡毒败血症感染导致感染个体的表观存活率较低，并且恢复率（从感染到未感染）大于该人群的感染率。我们还发现了强有力的证据表明，感染者比未感染者更不可能遇到。虽然我们预测性别和温度（生理条件的代理）可以解释我们数据中很大比例的变化，但这两个因素对表观生存率，遭遇率和状态转换率的影响很小。我们的分析确定了几个可能对野外疾病研究很重要的因素。首先，疾病状态分配可能是不确定的，这可能使参数估计复杂化。其次，在我们的研究中，受感染者的接触率相对于未受感染者较低，反映了受感染者可能的行为变化。低遭遇率降低了估计参数的精度，特别是对于多状态模型。最后，我们的研究结果（和标记-再捕获模型一般）假设个别鸟类之间的独立性。然而，我们意识到，在家雀（以及许多鸟类）中有一种社会结构。这种非独立性的会计可能是特别重要的情况下，状态转换直接关系到社会接触的模式。
1. We considered the impact of an emerging pathogen (Mycoplasma gallisepticum Edward and Kanarek) on apparent survival, encounter and transition rates in a population of a novel host (the house finch, Carpodacus mexicanus Muller). We used a multistate analysis of mark-encounter data from individually marked birds. Individual birds were categorized to a particular disease 'state'; transition rates among states, conditional on apparent survival, were analogous to rates of new infection and recovery from infection. We hypothesized that M. gallisepticum infection would reduce the apparent survival of infected individuals, and that the magnitude of this reduction would vary as a function of the physiological condition of the host (which was characterized in our analyses by including a demographic and an environmental surrogate as covariates).2. We found consistent support for the hypothesis that M. gallisepticum infection resulted in lower apparent survival among infected individuals, and that recovery rates (from infected to non-infected) were greater than infection rates in this population. We also found strong evidence indicating that infected individuals were less likely to be encountered than were non-infected individuals. Although we predicted that both sex and temperature (proxies for physiological condition) would explain a significant proportion of the variation in our data, only marginal influences of both factors on apparent survival, encounter and state transition rates were detected.3. Our analyses identified several factors that may be important to studies of disease in the wild. First, disease state assignment may be uncertain, which can complicate parameter estimation. Secondly, encounter rate for infected individuals in our study was low relative to that for non-infected individuals, reflecting possible behavioural changes in infected individuals. Low encounter rates reduces precision of estimated parameters, especially for multistate models. Finally, our results (and mark-recapture models in general) assume independence among individual birds. However, we are aware that there is a social structuring in house finches (and in general for many bird species). Accounting for such non-independence may be especially important for situations where the state transitions are directly related to the pattern of social contact.