Sequencing penA Gene of Strains with Decreased Susceptibility to Penicillin (PenI) Improves Typing of Meningococcal Isolates

摘要

Background: In Italy, the percentage of PenI strains increased from 24% in 2002 to 41% in 2007. In particular, after the emergence of the C:2b:P1.5,2 ST-8 complex/Cluster A4, as predominant clones of PenI strains, during the last two years we observed its gradual decrease together with the increase of serogroup B, W135 and Y PenI strains belonging to different clonal complexes. The mosaicism of the penA gene due to alterations mainly confined in the 3’ region has been used to monitor the penA changes among strains to improve typing of meningococci isolated over time.