Molecular Characterization of Pneumococcal Nasopharynx Isolates Collected from Children during Their First 2 Years of Life
AUTOR(ES)
Sluijter, Marcel
FONTE
American Society for Microbiology
RESUMO
Pneumococcal colonization was studied in 19 children monitored from birth through the age of 2 years. For this purpose, pneumococcal isolates were characterized by capsular typing, restriction fragment end labeling (RFEL), and penicillin-binding protein (PBP) genotyping. Fifty-eight isolates were collected and were found to belong to 10 capsular types, 31 RFEL types, and 7 PBP genotypes. Thirty-nine percent of the isolates had reduced susceptibility to penicillin. All seven highly resistant strains (MICs, >1 μg/ml) were identical to the pandemic clone 23F. Children were culture positive between one and eight times at 13 scheduled visits. Although the infants were frequently recolonized with different strains, colonization with one particular strain often persisted for several months. Isolation of a previously detected capsular type was common, and the chromosomal homogeneity tended to be high when it occurred. Horizontal transfer of capsular genes between strains of different RFEL types was demonstrated in one child. The ecological advantage of transfer of capsular genes is unclear unless survival of the organism on a mucosal surface may be linked to immunoprotective pressure against particular capsular types.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=105026Documentos Relacionados
- Cohort Study of Guinean Children: Incidence, Pathogenicity, Conferred Protection, and Attributable Risk for Enteropathogens during the First 2 Years of Life
- Rotavirus-inhibitory activity in serial milk samples from Mexican women and rotavirus infections in their children during their first year of life.
- Molecular Characterization of Avian Paramyxovirus 1 Isolates Collected from Cormorants in Canada from 1995 to 2000
- Molecular Characterization of Isolates of Waterborne Cryptosporidium spp. Collected during an Outbreak of Gastroenteritis in South Burgundy, France
- 3D analysis of effects of primary surgeries in cleft lip/palate children during the first two years of life