Which of the following is an example of active surveillance for avian influenza?

• A. Environmental fecal sampling year-round, targeted
• B. Active surveillance of apparently healthy birds via hunter harvest on flyways
• C. Morbidity/mortality monitoring year-round
• D. Syndromic data collection from hospitals

Answer: (B)

Active surveillance means proactively collecting data from a defined population to detect disease, even when individuals don’t show symptoms. Sampling apparently healthy birds through hunter harvest along migratory flyways fits this because it’s a planned, ongoing effort to obtain specimens from healthy-looking birds to monitor for avian influenza across key populations and routes. This approach seeks to detect the pathogen in the population before clinical signs or outbreaks occur, giving a clearer picture of prevalence and distribution.

In contrast, morbidity/mortality monitoring relies on reports of illness or death to signal problems, which is more reactive and depends on detected disease events rather than a proactive sampling plan. Syndromic data collection from hospitals targets human or veterinary clinical presentations, not birds, and environmental fecal sampling, while useful, collects material from the environment rather than directly sampling individual birds’ health status. This makes the hunter-harvest, healthy-bird sampling the quintessential example of active surveillance for avian influenza.