A multivalent vaccine is one that can protect against multiple strains of a pathogen. Synonyms for multivalent vaccine include polyvalent vaccine, combination vaccine, and multicomponent vaccine. Polyvalent vaccine refers specifically to a vaccine that can protect against different strains of the same disease, while combination and multicomponent vaccines protect against different diseases. Other synonyms for multivalent vaccine can include mixed vaccines or blended vaccines. Multivalent vaccines are particularly useful when there are multiple strains of a pathogen or when multiple diseases are prevalent in a community. They are often used in vaccination campaigns to protect large groups of people from a variety of diseases.