Which of the following is NOT a criterion of a successful eradication program?

• A. Small host range
• B. Acceptability to industry
• C. Effective diagnostic test for ID of carriers
• D. Large host range

Answer: (D)

Eradication programs succeed best when there are only a few species or populations that can harbor the pathogen, because a narrow host range limits reservoirs and transmission routes, making surveillance and elimination much more feasible. If the pathogen can infect many hosts, control becomes vastly more complex and unlikely to achieve zero incidence, since you’d have to monitor and interrupt transmission across multiple species and environments. Another essential element is acceptability to industry, which ensures that farmers and others will implement and sustain the necessary interventions. A reliable diagnostic test to identify carriers is also crucial, so you can detect infections early, isolate or remove affected animals, and accurately track progress. When a disease has a large host range, this combination of surveillance, industry cooperation, and effective testing becomes much harder to achieve, so a large host range is not a criterion that supports eradication.