• Vaccine Ontology ID: VO_0000672
• Type: Inactivated or "killed" vaccine
• Antigen: Heat-killed shigella flexneri strain 2a (Chakrabarti et al., 1999).
• Preparation: Each vacccine consisted of 10 ml of heat-killed bacteria, and each contained 10^11 CFU of bacteria (Chakrabarti et al., 1999).
• Virulence: Protection from diarrhea and dysentary following oral immunization was 100% .

Rabbit Response

• Host Strain: New Zealand white
• Vaccination Protocol: 25 male New Zealand white rabbits were given 10 ml of broth culture containing 10^11 CFU of the heat-killed bacteria. The vaccines were administered through injection of the colon. The rabbits were imminized for seven days, and were administered a total of 5 doses (Chakrabarti et al., 1999).
• Persistence: Not noted.
• Immune Response: The immune response can only be speculated upon, but it is believed that protective immunity to Shigella may by conferred by serum IgG antibodies to the O-specific polysaccaride of their lipopolysaccarides. There is also evidence that infection also confers type-specific immunity to LPS (Chakrabarti et al., 1999).
• Side Effects: Side effects included bloody diarrhea and dysentary (Chakrabarti et al., 1999).
• Challenge Protocol: Challenge specifics were not specifically noted.
• Efficacy: Challenge was only demonstrated using the same strain present inthe vaccine, and was eveidenced by lack of diarrhea. Death following challenge was 2.5 fold higher for non-immunized rabbits, but this was not significant (Chakrabarti et al., 1999).