What is sentinel surveillance in One Health and give an example.

• A. Surveillance limited to laboratory results only in hospitals.
• B. Targeted monitoring at selected sites to detect trends; example: sentinel veterinary clinics tracking influenza-like illness in animals and humans.
• C. Broad nationwide random sampling across all populations.
• D. Surveillance that ignores animal health.

Answer: (B)

Sentinel surveillance uses carefully chosen sites to continuously collect data so we can detect trends and early signals of disease without scanning every individual. By focusing on defined sentinel sites—such as specific clinics, farms, or sentinel cohorts—the system can monitor changes over time in a cost-effective way and flag outbreaks or shifts in transmission dynamics.

In One Health, this approach is especially valuable because it integrates human and animal health data at these sentinel sites. Diseases that move between animals and people, like influenza-like illness, benefit from this cross-species monitoring. An example is sentinel veterinary clinics that track influenza-like illness in animals and, when available, parallel data from humans in the same region. The pattern of illness across species at these targeted sites can reveal rising trends or spillover risk earlier than broad population sampling, enabling timely public health or veterinary interventions.

This differs from broad nationwide random sampling, which can be resource-heavy and slower to detect localized signals, and from approaches that ignore animal health, which miss crucial links in disease transmission within a One Health framework.