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

Which routes are responsible for the transmission of highly pathogenic avian influenza (HPAI) and virulent Newcastle's disease (vND)?

1. Only respiratory droplets

2. Feces and respiratory secretions

3. Via insects and other biological vectors

4. Only through contaminated water

The correct answer is: Feces and respiratory secretions

The correct response highlights the key transmission routes for highly pathogenic avian influenza (HPAI) and virulent Newcastle's disease (vND). Both of these diseases are transmitted primarily through feces and respiratory secretions, which are critical for understanding how these pathogens spread within and between bird populations. Feces can contain high viral loads, leading to environmental contamination. Infected birds shed the virus through their feces, and once it contaminates surfaces or feed, susceptible birds can become infected when they encounter the virus directly or indirectly. Additionally, respiratory secretions play a crucial role, as birds can transmit HPAI and vND during close contact through respiratory droplets. These droplets can remain viable in the environment, enabling further transmission. While other routes of transmission like contaminated water or vectors might contribute in specific scenarios, they are not the primary means by which these diseases spread across bird populations. As such, focusing on feces and respiratory secretions provides a more comprehensive understanding of the main pathways through which HPAI and vND propagate among birds, which is critical for managing and preventing outbreaks.