Frequent Transmission of Streptococcus pneumoniae Serotype 35B and 35D, Clonal Complex 558 Lineage, across Continents and the Formation of Multiple Clades in Japan

Abstract

Streptococcus pneumoniae is a common bacterial pathogen that causes infections in children worldwide, even after administration of the pneumococcal conjugate vaccine. S. pneumoniae serotype 35B, especially the clonal complex 558 (CC558) lineage, has emerged globally following implementation of the 13-valent pneumococcal conjugate vaccine. Serotype 35B strains are also associated with multidrug resistance to both β-lactams and non-β-lactam drugs.

Serotype replacement and an increase in non-encapsulated isolates among community-acquired infections of Streptococcus pneumoniae during post-vaccine era in Japan

“…Serotype 35B has emerged and expanded in various regions of the world, including Japan [ 5 , 6 , [22] , [23] , [24] ]. The increase is indicated to be due to clonal expansion of clonal complex (CC) 558, which is less susceptible to β-lactam antibiotics, and carries transposons containing macrolide- and tetracycline-resistant genes [25] and rrgC gene encoding an adhesin Pilus-1 [23] .…”

Ultrastructural, metabolic and genetic determinants of the acquisition of macrolide resistance byStreptococcus pneumoniae

“…Invasive and nasopharyngeal Spn strains carrying Tn 916 -related ICEs, including Tn 2009 and other ICEs, have been identified in China, Italy, Venezuela, USA, Spain, and the UK 28, 29, 32, 33 . Moreover, ∼90% of emergent Spn vaccine escape strains of serotype 35B and 35D, isolated in Japan, carry macrolide and tetracycline resistance determinants in Tn 916 -related ICEs; of these 75% Spn strains carried MEGA in Tn 2009 34 . Vaccine escape serotype 3 strains clonal complex (CC180) clade II, isolated in the USA and Hong Kong, carry ermB and tetM in a 36.7 kb Tn 916 -related ICE 35 .…”