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Postvaccine genetic structure of Streptococcus pneumoniae serotype 19A from children in the United States.
J Infect Dis. 2005 Dec 01; 192(11):1988-95.JI

Abstract

BACKGROUND

The introduction of the 7-valent conjugate pneumococcal vaccine (PCV7) in children may result in serotype replacement. We estimated the rate of increase of invasive pneumococcal disease (IPD) caused by serotype 19A in children <5 years old and determined the genetic composition of these isolates.

METHODS

Cases of IPD between July 1999 and June 2004 were identified through the Active Bacterial Core Surveillance. Serotype 19A isolates obtained from children <5 years old between January 2003 and June 2004 were characterized by serotyping, antibiotic susceptibility testing, and pulsed-field gel electrophoresis (PFGE). Select isolates representing homologous PFGE clusters were subjected to multilocus sequence typing, and eBURST was used to delineate clonal groups.

RESULTS

Between July 1999 and June 2004, the overall rate of IPD decreased from 23.3 to 13.1 cases/100,000 population (P<.00001). In children <5 years old, the rate decreased from 88.7 to 22.4 cases/100,000 population (P<.00001), whereas the rate in persons > or =5 years old decreased from 18.4 to 12.4 cases/100,000 population (P<.0001). The rate of serotype 19A IPD in children <5 years old increased significantly from 2.6 cases/100,000 population in 1999-2000 to 6.5 cases/100,000 population in 2003-2004; this was accompanied by significant increases in penicillin nonsusceptibility (P=.008) and multidrug resistance (P=.002) among serotype 19A isolates. As was observed during the pre-PCV7 era, clonal complex (CC) 199 predominated within serotype 19A, representing approximately 70% of invasive serotype 19A isolates from children <5 years old during 2003-2004. New serotype 19A genotypes were observed during 2003-2004, including 6 CCs that were not found among pneumococcal serotype 19A isolates during surveillance in 1999.

CONCLUSION

Serotype 19A is, at present, the most important cause of IPD by replacement serotypes, and it is increasingly drug resistant. CC199 is the predominant CC among type 19A serotypes in children <5 years old. Our data suggest that some of the increase in rates of infection with serotype 19A may be due to serotype switching within certain vaccine type strains.

Authors+Show Affiliations

Division of Bacterial and Mycotic Diseases, Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

16267772

Citation

Pai, Rekha, et al. "Postvaccine Genetic Structure of Streptococcus Pneumoniae Serotype 19A From Children in the United States." The Journal of Infectious Diseases, vol. 192, no. 11, 2005, pp. 1988-95.
Pai R, Moore MR, Pilishvili T, et al. Postvaccine genetic structure of Streptococcus pneumoniae serotype 19A from children in the United States. J Infect Dis. 2005;192(11):1988-95.
Pai, R., Moore, M. R., Pilishvili, T., Gertz, R. E., Whitney, C. G., & Beall, B. (2005). Postvaccine genetic structure of Streptococcus pneumoniae serotype 19A from children in the United States. The Journal of Infectious Diseases, 192(11), 1988-95.
Pai R, et al. Postvaccine Genetic Structure of Streptococcus Pneumoniae Serotype 19A From Children in the United States. J Infect Dis. 2005 Dec 1;192(11):1988-95. PubMed PMID: 16267772.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Postvaccine genetic structure of Streptococcus pneumoniae serotype 19A from children in the United States. AU - Pai,Rekha, AU - Moore,Matthew R, AU - Pilishvili,Tamara, AU - Gertz,Robert E, AU - Whitney,Cynthia G, AU - Beall,Bernard, AU - ,, Y1 - 2005/11/01/ PY - 2005/05/27/received PY - 2005/07/01/accepted PY - 2005/11/4/pubmed PY - 2006/1/20/medline PY - 2005/11/4/entrez SP - 1988 EP - 95 JF - The Journal of infectious diseases JO - J Infect Dis VL - 192 IS - 11 N2 - BACKGROUND: The introduction of the 7-valent conjugate pneumococcal vaccine (PCV7) in children may result in serotype replacement. We estimated the rate of increase of invasive pneumococcal disease (IPD) caused by serotype 19A in children <5 years old and determined the genetic composition of these isolates. METHODS: Cases of IPD between July 1999 and June 2004 were identified through the Active Bacterial Core Surveillance. Serotype 19A isolates obtained from children <5 years old between January 2003 and June 2004 were characterized by serotyping, antibiotic susceptibility testing, and pulsed-field gel electrophoresis (PFGE). Select isolates representing homologous PFGE clusters were subjected to multilocus sequence typing, and eBURST was used to delineate clonal groups. RESULTS: Between July 1999 and June 2004, the overall rate of IPD decreased from 23.3 to 13.1 cases/100,000 population (P<.00001). In children <5 years old, the rate decreased from 88.7 to 22.4 cases/100,000 population (P<.00001), whereas the rate in persons > or =5 years old decreased from 18.4 to 12.4 cases/100,000 population (P<.0001). The rate of serotype 19A IPD in children <5 years old increased significantly from 2.6 cases/100,000 population in 1999-2000 to 6.5 cases/100,000 population in 2003-2004; this was accompanied by significant increases in penicillin nonsusceptibility (P=.008) and multidrug resistance (P=.002) among serotype 19A isolates. As was observed during the pre-PCV7 era, clonal complex (CC) 199 predominated within serotype 19A, representing approximately 70% of invasive serotype 19A isolates from children <5 years old during 2003-2004. New serotype 19A genotypes were observed during 2003-2004, including 6 CCs that were not found among pneumococcal serotype 19A isolates during surveillance in 1999. CONCLUSION: Serotype 19A is, at present, the most important cause of IPD by replacement serotypes, and it is increasingly drug resistant. CC199 is the predominant CC among type 19A serotypes in children <5 years old. Our data suggest that some of the increase in rates of infection with serotype 19A may be due to serotype switching within certain vaccine type strains. SN - 0022-1899 UR - https://www.unboundmedicine.com/medline/citation/16267772/Postvaccine_genetic_structure_of_Streptococcus_pneumoniae_serotype_19A_from_children_in_the_United_States_ L2 - https://academic.oup.com/jid/article-lookup/doi/10.1086/498043 DB - PRIME DP - Unbound Medicine ER -