Final answer:
Heptavalent pneumococcal conjugate vaccine (PCV) is recommended for children younger than 2 years and adults older than 65 years to protect against pneumococcal bacteria and reduce the risk of serious illnesses such as pneumonia and meningitis.
Step-by-step explanation:
Heptavalent pneumococcal conjugate vaccine (PCV) is recommended for children younger than 2 years and adults older than 65 years. This vaccine helps protect against several strains of the pneumococcal bacteria, which can cause illnesses such as pneumonia, meningitis, and ear infections. It is especially important for these vulnerable populations to receive the vaccine to reduce their risk of serious complications.