Provided are methods for rapidly inactivating a pathogen, or for producing a vaccine composition containing an inactivated noninfectious pathogen having retained antigenicity and/or immunogenicity, comprising exposing the pathogen to a chemical inactivating agent (e.g., one or more chemical oxidizing, alkylating or crosslinking agents) in the presence of inorganic polyatomic oxyanions in an amount and for a time sufficient to render the pathogen noninfectious while enhancing retention of pathogen antigenicity and/or immunogenicity relative to that retained by contacting the pathogen with the chemical inactivating agent alone. The methods are broadly applicable to pathogens having RNA or DNA genomes (e.g., including viruses, bacteria, fungi, and parasites). Also provided are vaccine compositions (medicaments) containing a pathogen inactivated by exposure to a an inactivating agent in the presence of elevated concentrations of inorganic polyatomic oxyanions, and methods for eliciting an immune response in a subject by administering the vaccine compositions.
