The Heterogeneity of Endemic Community Pediatric Group A Streptococcal Pharyngeal Isolates and Their Relationship to Invasive Isolates

• Published in: The Journal of infectious diseases 2002-04, Vol.185 (7), p.915-920
• Main Authors: Haukness, Heather A., Tanz, Robert R., Thomson, Richard B., Pierry, Deirdre K., Kaplan, Edward L., Beall, Bernard, Johnson, Dwight, Hoe, Nancy P., Musser, James M., Shulman, Stanford T.
• Format: Article
• Language: English
• Subjects: Adolescent; Alleles; Bacterial diseases; Bacterial Proteins - genetics; Biological and medical sciences; Child; Child, Preschool; Electrophoresis; Electrophoresis, Gel, Pulsed-Field; Endemic Diseases; Epidemiology; Exotoxins - genetics; Gels; Genetic Variation; Human bacterial diseases; Humans; Infant; Infant, Newborn; Infections; Infectious diseases; Major Articles; Medical sciences; Membrane Proteins - genetics; Nursing homes; Pediatrics; Pharyngitis; Pharynx - microbiology; Serotyping; Staphylococcal infections, streptococcal infections, pneumococcal infections; Streptococcal Infections - epidemiology; Streptococcal Infections - microbiology; Streptococcus pyogenes; Streptococcus pyogenes - classification; Streptococcus pyogenes - genetics; Streptococcus pyogenes - isolation & purification; Streptococcus pyogenes - pathogenicity; Toxins
• ISSN: 0022-1899; 1573-6613; 1537-6613
• DOI: 10.1086/339407

By use of molecular techniques, the genetic heterogeneity of 63 community pediatric pharyngeal group A streptococcal (GAS) isolates circulating within a 3-week period were compared with 17 contemporaneous invasive pediatric isolates. Pharyngitis isolates represented 16 pulsed-field gel electrophoresis (PFGE) patterns with 12 emm serotypes, and invasive isolates represented 10 PFGE patterns with 9 emm serotypes. One-fourth of the pharyngeal isolates (16/63) were identical to at least 1 invasive isolate; conversely, 10 (59%) of 17 invasive isolates were identical to at least 1 pharyngeal strain. sic allele analysis of emm1 strains demonstrated additional heterogeneity and overlap. More pharyngeal (71%) than invasive isolates (35%) were positive for both speA and speC (P < .02). Many pharyngitis GAS strains circulate simultaneously. Most invasive pediatric GAS strains are identical to acute pharyngitis strains; thus, childhood pharyngitis is a major reservoir for strains with invasive potential. Pharyngeal isolates were more likely to be speA and speC positive than were the invasive isolates.