Routine childhood immunizations represent one of the greatest achievements in public health, preventing millions of deaths annually from infectious diseases such as measles, mumps, rubella, pertussis, Haemophilus influenzae type b, and polio. Maintaining high community vaccination rates (≥ 95%) is vital for shielding immunocompromised individuals who cannot receive live vaccines.
Herd Immunity Thresholds for Infectious Pathogens
| Pathogen | Basic Reproduction Number (R₀) | Herd Immunity Threshold (HIT) |
|---|---|---|
| Measles | 12 – 18 | 92% – 95% |
| Pertussis (Whooping Cough) | 12 – 17 | 92% – 94% |
| Diphtheria | 6 – 7 | 83% – 85% |
| Polio | 5 – 7 | 80% – 86% |
| Mumps | 4 – 7 | 75% – 86% |