Pneumococcal carriage and invasive disease in children before introduction of the 13-valent conjugate vaccine: comparison with the era before 7-valent conjugate vaccine. - Sharma D; Baughman W; Holst A; Thomas S; Jackson D; da Gloria Carvalho M; Beall B; Satola S; Jerris R; Jain S; Farley MM; Nuorti JP (The Pediatric infectious disease journal, 2013)