Data on hamster LD50 from Leptospira and its impact on Title 9, Codified Federal Regulations Sections 113.102–113.103 test validity

These data and analyses support the research article “Re-evaluating the LD50 requirements in the codified potency testing of veterinary vaccines containing Leptospira serogroups Icterohaemorrhagiae and Canicola in the United States” (Walker et al., 2018). Validity and disposition requirements submitted to the Center for Veterinary Biologics (CVB) are provided for serials (numbered lots) of commercial product potency tested for serogroups Canicola and Icterohaemorrhagiae in support of the Virus-Serum-Toxin Act (VSTA). Time course data for hamster loss after challenge with various concentrations of Leptospira during codified potency testing are also presented. The dose of Leptospira lethal to 50% of hamsters (LD50) was calculated by the Dragstedt-Behrens method for the in vivo data collected, and the equation is described here.