Strasburg Miranda, Christensen Sonja
Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824, USA.
Pathogens. 2024 Jun 28;13(7):545. doi: 10.3390/pathogens13070545.
Disease co-occurrence in wildlife populations is common yet understudied. In the case of disease-caused mortality, the mortality attributed to one disease has the potential to buffer populations against subsequent alternative disease outbreaks by reducing populations and thus contacts needed to sustain disease transmission. However, substantial disease-driven population declines may also prevent populations from recovering, leading to localized extinctions. Hemorrhagic disease (HD), a vector-transmitted, viral disease in white-tailed deer (WTD), similar to chronic wasting disease (CWD), a prion disease, has increased in frequency and distribution in the United States. However, unlike CWD, which progresses slowly, HD can cause mortality only days after infection. Hemorrhagic disease outbreaks can result in substantial localized mortality events in WTD near vector habitats such as wetlands and may reduce local deer densities and consequent CWD transmission. The objective of our study was to evaluate the potential for HD outbreaks to buffer CWD risk where the diseases co-occur. Using an agent-based modeling approach, we found that frequent, intense HD outbreaks have the potential to mitigate CWD risk, especially if those outbreaks occur shortly after CWD introduction. However, HD outbreaks that do not result in substantial WTD mortality are unlikely to impact CWD or WTD population dynamics. Severe HD outbreaks may reduce CWD cases and could present an opportunity for managers to boost CWD control initiatives in a post-HD outbreak year.
野生动物种群中疾病共发的情况很常见，但却未得到充分研究。就疾病导致的死亡率而言，一种疾病造成的死亡有可能通过减少种群数量以及维持疾病传播所需的接触，来缓冲种群抵御随后的其他疾病爆发。然而，由疾病驱动的大量种群数量下降也可能阻止种群恢复，导致局部灭绝。出血性疾病（HD）是一种通过媒介传播的白尾鹿（WTD）病毒性疾病，与朊病毒疾病慢性消耗病（CWD）类似，在美国其发病频率和分布范围都有所增加。然而，与进展缓慢的CWD不同，HD在感染后仅数天就能导致死亡。出血性疾病爆发可在湿地等媒介栖息地附近的白尾鹿中引发大量局部死亡事件，并可能降低当地鹿的密度以及随之而来的CWD传播。我们研究的目的是评估HD爆发在两种疾病共发地区缓冲CWD风险的潜力。使用基于主体的建模方法，我们发现频繁、强烈的HD爆发有可能减轻CWD风险，特别是如果这些爆发在CWD引入后不久就发生。然而，不会导致白尾鹿大量死亡的HD爆发不太可能影响CWD或白尾鹿种群动态。严重的HD爆发可能会减少CWD病例，并可能为管理者提供一个机会，在HD爆发后的年份加强CWD控制措施。
