Rapid pneumococcal evolution in response to clinical interventions.

Journal article

Epidemiological studies of the naturally transformable bacterial pathogen Streptococcus pneumoniae have previously been confounded by high rates of recombination. Sequencing 240 isolates of the PMEN1 (Spain(23F)-1) multidrug-resistant lineage enabled base substitutions to be distinguished from polymorphisms arising through horizontal sequence transfer. More than 700 recombinations were detected, with genes encoding major antigens frequently affected. Among these were 10 capsule-switching events, one of which accompanied a population shift as vaccine-escape serotype 19A isolates emerged in the USA after the introduction of the conjugate polysaccharide vaccine. The evolution of resistance to fluoroquinolones, rifampicin, and macrolides was observed to occur on multiple occasions. This study details how genomic plasticity within lineages of recombinogenic bacteria can permit adaptation to clinical interventions over remarkably short time scales.

Authors: Croucher, N; Harris, SR; Fraser, C; Quail, M; Burton, J

• Publication status: Published
• Journal: Science (New York, N.Y.)
• Volume: 331
• Issue: 6016
• Pages: 430-434
• Publication date: 2011-01-01
• DOI: 10.1126/science.1198545
• EISSN: 1095-9203
• ISSN: 0036-8075
• Language: English
• Keywords: Streptococcus Phages; Serotyping; DNA Transposable Elements; Pneumococcal Infections; Phylogeography; Molecular Epidemiology; Adaptation, Physiological; Genome, Bacterial; Streptococcus pneumoniae; Recombination, Genetic; Pneumococcal Vaccines; Drug Resistance, Multiple, Bacterial; Humans; Polymorphism, Single Nucleotide; Selection, Genetic; Evolution, Molecular; Prophages; Anti-Bacterial Agents; Antigenic Variation; Phylogeny