Genetic variability of <i>Bordetella pertussis</i> and its role in vaccine prevention of pertussis

Abstract

In many countries of the world despite the extensively vaccination against pertussis has increased the incidence of the whooping cough in all age group of the population. The MLST, MLVA and CGH investigations revealed the differences in genotypes between the vaccine strains B.pertussis and the circulating isolates B.pertussis in consequence of adaptation of the bacterium B.pertussis to the immunized hosts. It is lead to waning immynity and outbreak of incidence of pertussis. The mutations in the genes encoding the major virulence factors, the allelic polimorfism and decreasing the genome size of B.pertussis strains are the basis of the B.pertussis adaptation to the immunized hosts and dependent on the type of the vaccine used for immunization Programme. In countries that use acellular pertussis vaccine for vaccination programme the dominant isolates genotypes are: ptxА1-ptxС2- ptxР3-prn2- tcfA2-1-fim3-2 и ptxА1- ptxС2- ptxР3-prnА2- tcfA2- fim2-1- fim3-1, and that use the cellular pertussis vaccine the dominant isolates genotypes are ptxА1-ptxС1- ptxР1-prn1- tcfA2- fim2-2 fim3-1 и ptxА1- ptxС1- ptxР1- prn2- tcfA2- fim2-1- fim3-1. The constant monitoring of the genotypes of isolates B.pertussis is necessary to reveal the dominant genotypes and include them in the national immunization programme in combination with vaccine strains B.pertussis.

Keywords

• pertussis
• <i>b. pertussis</i> vaccine strains
• <i>b. pertussis</i> circulating strains
• isolate
• dominant genotypes
• genes