Are vaccination programs and isolate polymorphism linked to pertussis re-emergence?

Area of Science:

• Immunology
• Microbiology
• Epidemiology

Background:

• Whooping cough (pertussis) remains endemic globally.
• Increased pertussis incidence is observed in adolescents and adults, even with high vaccination rates.
• Bordetella pertussis strains have shown genetic and phenotypic variability over time.

Purpose of the Study:

• To review current knowledge on Bordetella pertussis variability.
• To discuss the impact of B. pertussis evolution on pertussis re-emergence.
• To explore factors contributing to increased whooping cough incidence in vaccinated populations.

Main Methods:

• Literature review of studies on Bordetella pertussis isolates.
• Analysis of pertussis epidemiology in countries with varying vaccination programs.
• Examination of B. pertussis genetic and antigenic characteristics.

Main Results:

• No direct link found between B. pertussis isolate variability and specific vaccination programs, except for fimbriae shifts (Fim2 to Fim3).
• Pertussis epidemiology and transmission patterns have changed in highly vaccinated populations.
• Disease incidence has shifted from young children to adolescents and adults.

Conclusions:

• Waning protective immunity is a significant factor in pertussis re-emergence.
• Changes in transmission dynamics contribute to increased whooping cough cases in adolescents and adults.
• Further research is needed to understand the interplay between B. pertussis evolution and public health strategies.