TY - JOUR
T1 - Molecular epidemiology of Bordetella pertussis in the Philippines in 2012-2014
AU - Tohoku-RITM Collaborating Research Team
AU - Galit, Salvacion Rosario L.
AU - Otsuka, Nao
AU - Furuse, Yuki
AU - Almonia, Daryl Joy V.
AU - Sombrero, Lydia T.
AU - Capeding, Rosario Z.
AU - Lupisan, Socorro P.
AU - Saito, Mariko
AU - Oshitani, Hitoshi
AU - Hiramatsu, Yukihiro
AU - Shibayama, Keigo
AU - Kamachi, Kazunari
PY - 2015/6/1
Y1 - 2015/6/1
N2 - Objectives: The present study was designed to determine the genotypes of circulating Bordetella pertussis in the Philippines by direct molecular typing of clinical specimens. Methods: Nasopharyngeal swabs (NPSs) were collected from 50 children hospitalized with pertussis in three hospitals during 2012-2014. Multilocus variable-number tandem repeat analysis (MLVA) was performed on the DNA extracts from NPSs. B. pertussis virulence-associated allelic genes (. ptxA, prn, and fim3) and the pertussis toxin promoter, ptxP, were also investigated by DNA sequence-based typing. Results: Twenty-six DNA extracts yielded a complete MLVA profile, which were sorted into 10 MLVA types. MLVA type 34 (MT34), which is rare in Australia, Europe, Japan, and the USA, was the predominant strain (50%). Seven MTs (MT29, MT32, MT33, and MT283-286, total 42%) were single-locus variants of MT34, while two (MT141 and MT287, total 8%) were double-locus variants of MT34. All MTs had the combination of virulence-associated allelic genes, ptxP1-. ptxA1-. prn1-. fim3A. Conclusions: The B. pertussis population in the Philippines comprises genetically related strains. These strains are markedly different from those found in patients from other countries where acellular pertussis vaccines are used. The differences in vaccine types between these other countries and the Philippines, where the whole-cell vaccine is still used, may select for distinct populations of B. pertussis.
AB - Objectives: The present study was designed to determine the genotypes of circulating Bordetella pertussis in the Philippines by direct molecular typing of clinical specimens. Methods: Nasopharyngeal swabs (NPSs) were collected from 50 children hospitalized with pertussis in three hospitals during 2012-2014. Multilocus variable-number tandem repeat analysis (MLVA) was performed on the DNA extracts from NPSs. B. pertussis virulence-associated allelic genes (. ptxA, prn, and fim3) and the pertussis toxin promoter, ptxP, were also investigated by DNA sequence-based typing. Results: Twenty-six DNA extracts yielded a complete MLVA profile, which were sorted into 10 MLVA types. MLVA type 34 (MT34), which is rare in Australia, Europe, Japan, and the USA, was the predominant strain (50%). Seven MTs (MT29, MT32, MT33, and MT283-286, total 42%) were single-locus variants of MT34, while two (MT141 and MT287, total 8%) were double-locus variants of MT34. All MTs had the combination of virulence-associated allelic genes, ptxP1-. ptxA1-. prn1-. fim3A. Conclusions: The B. pertussis population in the Philippines comprises genetically related strains. These strains are markedly different from those found in patients from other countries where acellular pertussis vaccines are used. The differences in vaccine types between these other countries and the Philippines, where the whole-cell vaccine is still used, may select for distinct populations of B. pertussis.
KW - Bordetella pertussis
KW - Genotype
KW - Multilocus variable-number tandem repeat analysis
KW - Philippines
KW - Virulence-associated allelic gene
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U2 - 10.1016/j.ijid.2015.04.001
DO - 10.1016/j.ijid.2015.04.001
M3 - Article
C2 - 25861926
AN - SCOPUS:84928338180
VL - 35
SP - e24-e26
JO - International Journal of Infectious Diseases
JF - International Journal of Infectious Diseases
SN - 1201-9712
ER -