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

Is it possible for chickens infected with low pathogenicity avian influenza to be the source of a virus for a flock infected with highly pathogenic avian influenza (HPAI)?

1. No, only high pathogenicity viruses can spread

2. Yes, low pathogenicity can lead to high pathogenicity

3. It depends on the environmental conditions

4. No, they do not interact

The correct answer is: Yes, low pathogenicity can lead to high pathogenicity

Chickens infected with low pathogenicity avian influenza have the potential to contribute to the emergence of highly pathogenic avian influenza (HPAI) viruses. Low pathogenicity avian influenza viruses can mutate over time, particularly under selective pressures such as those created by widespread infections or vaccinations. This mutation can result in the virus acquiring traits that enhance its virulence, transforming a previously mild strain into a highly pathogenic one. This process is known as reassortment, where genetic material from different strains of the influenza virus combines, leading to a more virulent variant. In a flock where low pathogenicity avian influenza is present, continued infection and interaction among chickens can foster an environment conducive to such genetic changes, highlighting the intricate relationship between low and high pathogenicity strains. Understanding this risk is crucial for biosecurity measures in poultry management, as it underscores the need for surveillance and control of both low and high pathogenic strains. This concept is vital for preventing outbreaks that can have devastating effects on poultry health and industry economics.