Okinawa Prefectural Nanbu Medical Center & Children’s Medical Center, Okinawa, Japan;
Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan;
Nakamura Clinic Pediatric, Dermatology and Internal Medicine, Okinawa, Japan;
Awase Daiichi Clinic, Okinawa, Japan;
Syuri Child Clinic, Okinawa, Japan;
Wanpaku Clinic, Okinawa, Japan;
The Okinawa Society of Child Health, Okinawa, Japan;
Nasopharynx; Carriage; Pneumococcal; Conjugate; Vaccine; Japan; Young; Children;