Bordetella pertussis Strains Circulating in Europe in 1999 to 2004 as Determined by Pulsed-Field Gel Electrophoresis

Abstract

and United Kingdom, were analyzed by pulsed-field gel electrophoresis (PFGE), and their PFGE profiles were compared with those of isolates collected in 1999 (n ‫؍‬ 102). The 255 isolates produced 59 distinct PFGE profiles. Among the 153 isolates from 2004, 36 profiles were found, while within the 102 isolates from 1999, 33 profiles were detected. One PFGE profile, BpSR11, was dominant (30% to 50%) in all countries except Denmark (10%) and Poland (0%). In comparison with 1999, there was an increase in BpSR11 prevalence in Finland in 2004 from 5% to 40%, coinciding with a major incidence peak. Some other PFGE profiles seemed to be associated with limited dissemination. Poland was the only country in which the most common actual European PFGE profiles were not found. In a dendrogram analysis, all common PFGE profiles were identified within PFGE group IV, and BpSR11 clustered together with PFGE subgroup IV␤. Compared to the 1999 isolates, PFGE group V representative for pertactin variant prn3 strains had disappeared, and a new cluster was seen. In conclusion, some PFGE profiles, such as BpSR11, evidently have a higher capacity to spread, suggesting increased fitness to the present immunological environment. It is therefore of major interest to continue with surveillance programs of B. pertussis isolates, as both waning vaccine-derived immunity and strain variation may play a role in the persistence of pertussis.

Strain Variation among Bordetella pertussis Isolates Circulating in Poland after 50 Years of Whole-Cell Pertussis Vaccine Use

“…Vaccine-driven evolution in the B. pertussis population measured by genetic and antigenic shifts is still hypothesized (5,13,19,29,32,33,34,36,42) since it was first suggested by Khattak et al (23,24). Epidemiological surveys of B. pertussis strains on the genome and gene levels have found recent isolates distinct from vaccine strains or isolates circulating before the 1990s in many countries using different typing methods (5,8,13,14,18,19,29,30,43).…”

“…Epidemiological surveys of B. pertussis strains on the genome and gene levels have found recent isolates distinct from vaccine strains or isolates circulating before the 1990s in many countries using different typing methods (5,8,13,14,18,19,29,30,43). PFGE, multilocus sequence typing, and multilocus variable-number tandem repeat analysis have found some B. pertussis lineages to be more successful at disseminating and/or related to the increase of incidence in some countries (2,3,12,19,25,38). Among many available methodologies capable of tracking genetic differences among isolates, PFGE has been the chosen reference method for epidemiological surveys (2,31), since it is the most discriminatory (4).…”

Resurgence of pertussis calls for re-evaluation of pertussis animal models

“…Coinciding with the observed increase of pertussis in various vaccinating countries, antigenic mutations were noted in circulating B. pertussis strains all over the world [32,39,40]. In The Netherlands, a country with an overall high vaccination coverage of more than 95%, the rise in pertussis notifications in the 1990s concurred highly with the switch in the Ptx promoter (ptxP) region from the ptxP1 allele to the ptxP3 allele [41].…”

Efficacy and effectiveness of acellular pertussis vaccines: a 20-year Swedish experience

“…A shift of antigenic properties of B. pertussis virulence factors may be essential for the susceptibility of the human population to infection. For this reason, a European research program for the collection of strains and strain characterization, EUpertstrain, has been established [21]. Hopefully, new technology will provide another layer of information concerning adaptation of B. pertussis to the host.…”