Pneumonia vaccine, also known as pneumococcal vaccine, is a type of immunization that helps protect against infections caused by Streptococcus pneumoniae bacteria. These infections can lead to pneumonia, meningitis, and sepsis. There are two types of pneumococcal vaccines: pneumococcal conjugate vaccine (PCV13) and pneumococcal polysaccharide vaccine (PPSV23), which protect against different strains of the bacteria.