Antigenic divergence of Bordetella pertussis isolates in Taiwan.
In recent studies, antigenic divergence has been observed in Bordetella pertussis circulating isolates. We collected 80 Bordetella pertussis isolates in Taiwan from 1998 to 2004 and analyzed them using a combination of pulsed-field gel electrophoresis (PFGE) and sequencing of the ptxS1 and prn genes. The incidence of pertussis increases every 3 years, and most of the isolates prevalent since 1998 have expressed nonvaccine ptxS1A and prn2 alleles. Through PFGE analysis, all isolates could be classified into four major groups, and the incidence of these groups exhibited a correlation with the prn allele expressed by the isolates. We found that PFGE is more discriminative than gene sequencing, since it could divide the isolates expressing the prn2 allele into two groups: one group circulating from 1998 to 2001 and another group circulating from 2001 to 2004. The transition between the two groups in 2000 coincided with an outbreak of 326 cases. This research indicates that the antigenic divergence of B. pertussis circulating isolates has evolved over time in Taiwan. Such information will have implications for vaccine policy in Taiwan.
Yao
Shu-Man
SM
Laboratory for Bacteriology and Mycology, Center for Research and Diagnostics, Taipei, Taiwan.
Lin
Yu-Chi
YC
Chou
Chen-Ying
CY
Chen
Ying-Yan
YY
Hsiao
Miao-Ju
MJ
Chen
Hour-Young
HY
Yan
Jer-Jea
JJ
Su
Hsun-Pi
HP
Li
Shu-Ying
SY
D000483:Alleles; D000940:Antigenic Variation / Q000235:genetics*; D001483:Base Sequence; D001886:Bordetella pertussis / Q000145:classification / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D005798:Genes, Bacterial; D006801:Humans; D013624:Taiwan; D014917:Whooping Cough / Q000382:microbiology*