Immunogenicity and safety study of 23-valent pneumococcal polysaccharide vaccine revaccination among elderly individuals aged 60–70 years in Shanghai, China
BackgroundTo understand the immunogenicity and safety of the 23-valent pneumococcal polysaccharide vaccine in elderly individuals aged 60–70 years in Shanghai after revaccination.MethodsA total of 330 elderly people aged 60–70 years were recruited to s…