Factors Affecting Vaccination Programme Success

Steps:

• Identify key factors: population coverage for herd immunity, vaccine efficacy, logistics like cold chain, and public compliance.
• Evaluate each against success criteria: must enable majority immunity without major barriers.
• Match symbols to factors: ✓ for impacts success, × for minimal or no impact.
• Select row aligning with established epidemiology principles.

Why B is correct:

• Matches herd immunity requiring >80% coverage (✓), stable disease incidence not directly affecting (×), effective vaccine delivery (✓), and high acceptance rates (✓), per WHO vaccination guidelines.

Why the others are wrong:

• A: Incorrectly marks coverage as non-impact (×), ignoring herd immunity threshold.
• C: Falsely excludes coverage (×) and acceptance (×), underestimating compliance role.
• D: Misses efficacy and acceptance (× ×), violating core immunization success factors.

Final answer: B