Based on the provided information, it can be concluded that the reduction in pertussis incidence in recent decades in many countries is directly linked to the widespread use of vaccines against this disease. However, there are other factors that may influence the situation.
### Key Points:
1. **Vaccine Development:**
- Japan developed a cell-free vaccine DTP (vaccine for diphtheria, tetanus, and pertussis), which causes less immune response compared to traditional vaccines.
- Russia has developed the first Russian combined adult vaccine aDTpaP-M, which showed high efficacy without serious side effects.
2. **Vaccine Effectiveness:**
- Vaccination provides protection up to 73% in the first year after administration and decreases to 34% four years later.
- Mass prevention using vaccines significantly reduces pertussis incidence.
3. **Disease Statistics:
- In England, 433 cases of pertussis were identified among children under 3 months old in 2023, 889 cases among children aged from 1 to 4 years and 8856 cases among teenagers and adults over 15 years old.
- In Sweden, after discontinuing the DTP vaccine, the number of sudden infant deaths increased, indicating the importance of vaccination.
4. **Research and Myths:
- Despite some research on side effects such as post-vaccination seizure syndrome, the overall efficacy and safety of pertussis vaccines are confirmed by numerous studies.
### Conclusion:
Vaccination is a key factor in reducing pertussis incidence. Despite certain myths and concerns, scientific data shows high vaccine effectiveness and minimal risk of serious side effects.
It's important for parents to understand the importance of vaccination before school to ensure protection against pertussis for their children.