Transboundary Emerging and Exotic Animal Disease/ Exotic Animal Disease Practice Exam

What is a primary risk factor for the introduction of classical swine fever to the U.S.?

1. Ticks on feral swine

2. Hitchhiking mosquitoes from infected areas

3. Importation of breeding stock from Canada

4. Infected non-clinical pigs and contaminated meat

The correct answer is: Infected non-clinical pigs and contaminated meat

The introduction of classical swine fever (CSF) to the U.S. primarily hinges on the risk presented by infected non-clinical pigs and contaminated meat. Non-clinical pigs can carry the virus without showing obvious symptoms, making it difficult to detect and manage. These pigs can be a silent reservoir for the disease, potentially facilitating its transmission to domestic swine populations if they come into contact. Furthermore, contaminated meat products pose a significant risk as they may harbor the virus, and if fed to pigs or if they come into contact with swine environments, the virus can spread rapidly. While other factors like ticks, mosquitoes, and the importation of breeding stock do carry risk, they are less significant compared to the direct risks from infected animals and contaminated products. Ticks and mosquitoes have limited host interaction and transmission capabilities for CSF compared to the potential impact of asymptomatic carriers and contaminated food sources, which can directly lead to outbreaks in swine populations. Importation of breeding stock also requires stringent health measures and inspections, thus reducing the likelihood of disease introduction via this route compared to the more insidious threat posed by infected non-clinical pigs and contaminated meat.