Pneumococcal refers to infections caused by the bacterium Streptococcus pneumoniae, which can lead to serious illnesses such as pneumonia, meningitis, and bloodstream infections. This bacterium is commonly found in the respiratory tract and can spread through respiratory droplets when an infected person coughs or sneezes. Vaccines are available to help prevent pneumococcal infections, particularly in vulnerable populations like young children, the elderly, and individuals with weakened immune systems. The two main types of pneumococcal vaccines are the pneumococcal conjugate vaccine (PCV) and the pneumococcal polysaccharide vaccine (PPSV), both of which aim to reduce the risk of severe disease.