The full name of the 23-valent vaccine is 23-valent pneumococcal vaccine, and the 23-valent pneumococcal vaccine is usually administered in one dose, while high-risk groups can receive two doses. The 23-valent pneumococcal vaccine is usually given as a single dose and is usually indicated for young children over 2 years of age with recurrent pneumonia and for those at high risk of developing pneumonia. 23-valent pneumococcal vaccine provides protection of more than 92% and has a good safe immunity for up to five years. Systematic revaccination is not recommended for those who have already received pneumococcal vaccine. However, if a person is at high risk for pneumococcal infection, a 2nd dose is recommended. People at high risk for pneumonia include those who live or work in environments with a high risk for streptococcus, people with nephrotic syndrome, kidney failure, or organ transplantation, and people with HIV infection. The 23-valent pneumococcal vaccine is a self-funded vaccine, which is a free vaccine relative to the national immunization program. It is not a mandatory vaccine required by the state, and is voluntary, so parents can selectively vaccinate their babies.