Prevalence of pilus encoding islets among acute otitis media Streptococcus pneumoniae isolates from Israel.

Abstract

We evaluated the distribution of the two known Streptococcus pneumoniae pilus encoding islets (PI-1 and PI-2) among a panel of 113 acute otitis media clinical isolates from Israel. PI-1 was present in 30.1% (n = 34) of the isolates tested, and PI-2 was present in 7% (n = 8). In addition, we found that: (i) the PI positive isolates, 50% of which belong to the international clones Spain(9V)-3 (ST156) and Taiwan(19F)-14 (ST236), correlate with the genotype (as determined by multilocus sequence typing) but not with the serotype; (ii) PI-2 was not present in the absence of Pl-1; and (iii) the frequency of PI-1 was higher among antibiotic-resistant isolates.