Re-emergence of the type 1 pilus among Streptococcus pneumoniae isolates in Massachusetts, USA

G Regev-Yochay, WP Hanage, K Trzcinski… - Vaccine, 2010 - Elsevier
G Regev-Yochay, WP Hanage, K Trzcinski, SL Rifas-Shiman, G Lee, A Bessolo, SS Huang…
Vaccine, 2010Elsevier
Pneumococcal type 1 pilus proteins have been proposed as potential vaccine candidates.
Following conjugate pneumococcal vaccination, the prevalence of the pneumococcal type 1
pilus declined dramatically, a decline associated with the elimination of vaccine-type (VT)
strains. Here we show that between 2004 and 2007, there has been a significant increase in
pilus prevalence, now exceeding rates from the pre-conjugate vaccine era. This increase is
primarily due to non-VT strains. These emerging piliated non-VT strains are mostly novel …
Pneumococcal type 1 pilus proteins have been proposed as potential vaccine candidates. Following conjugate pneumococcal vaccination, the prevalence of the pneumococcal type 1 pilus declined dramatically, a decline associated with the elimination of vaccine-type (VT) strains. Here we show that between 2004 and 2007, there has been a significant increase in pilus prevalence, now exceeding rates from the pre-conjugate vaccine era. This increase is primarily due to non-VT strains. These emerging piliated non-VT strains are mostly novel clones, with some exceptions. The rise in pilus type 1 frequency across multiple distinct genetic backgrounds suggests that the pilus may confer an intrinsic advantage.
Elsevier