Foreign Animal Disease Research Unit, Agriculture Research Service, US Department of Agriculture, Plum Island Animal Disease Center, Greenport, NY 11944, USA.
Vet J. 2012 Aug;193(2):456-63. doi: 10.1016/j.tvjl.2012.01.012. Epub 2012 Feb 17.
A novel direct contact transmission model for the study of foot-and-mouth disease virus (FMDV) infection of swine was utilized to investigate transmission characteristics of three FMDV strains belonging to serotypes A, O and Asia1. Each strain demonstrated distinct transmission characteristics and required different exposure times to achieve successful contact transmission. While a 4h exposure was sufficient for strain A24 Cruzeiro (A24Cru), both O1 Manisa and Asia1 Shamir transmission required 18 h or more. Viral excretion levels from donors (for all three strains) and virus present in room air (for A24Cru and O1 Manisa) were evaluated and associated with clinical signs and observed transmission pattern. Although all directly inoculated donor animals showed acute FMD, A24Cru had the highest levels of viral shedding in saliva and nasal swabs followed by O1 Manisa and Asia1 Shamir. Virus levels in room air were higher and were detected longer for A24Cru than for O1 Manisa. These results provide direct evidence for important strain-specific variation in transmission characteristics and emphasize the need for thorough evaluation of different FMDV viral strains using a well defined contact transmission methodology. This information is critical for vaccine and biotherapeutic efficacy testing, pathogenesis and disease modeling of FMDV transmission.
我们利用一种新型的直接接触传播模型来研究口蹄疫病毒（FMDV）对猪的感染，该模型用于研究三种血清型 A、O 和 Asia1 的 FMDV 菌株的传播特征。每种菌株都表现出不同的传播特征，并且需要不同的暴露时间来实现成功的接触传播。虽然 A24Cruzeiro（A24Cru）菌株的 4 小时暴露就足以实现，但 O1 Manisa 和 Asia1 Shamir 菌株的传播则需要 18 小时或更长时间。我们评估了供体（所有三种菌株）的病毒排出水平和室内空气中的病毒（对于 A24Cru 和 O1 Manisa），并将其与临床症状和观察到的传播模式相关联。尽管所有直接接种的供体动物都表现出急性口蹄疫，但 A24Cru 在唾液和鼻腔拭子中的病毒脱落水平最高，其次是 O1 Manisa 和 Asia1 Shamir。A24Cru 室内空气中的病毒水平更高，且检测到的时间也比 O1 Manisa 更长。这些结果为传播特征的重要菌株特异性变异提供了直接证据，并强调需要使用定义明确的接触传播方法对不同的 FMDV 病毒株进行彻底评估。这些信息对于 FMDV 传播的疫苗和生物治疗效果测试、发病机制和疾病建模至关重要。
