Resistance to Viral Challenge in the Days Immediately Following Vaccination
Abstract
Mice vaccinated with 17D yellow fever virus, intracerebrally challenged from 1 to 4 days later with the French viscerotropic strain of yellow fever, were substantially protected; when the challenge was with a neurotropic strain, Asibi, no protection was observed. The former strain was slow to invade and cause death with an average survival time 2 to 2 1/2 times longer than that of Asibi strain. Challenge with a small dose of VEE virus of mice vaccinated with JE vaccine revealed a moderate but significant protection 24 hours, but not seven days, after vaccination; this is another example of non-specific early resistance after vaccination. Cytoxan given repeatedly at the time of vaccination and challenge to inhibit early non-specific resistance after vaccination. It would seem that with an adequate model it can be shown that this early resistance is independent of the immune system. Resistance following vaccination of guinea pigs with EEE virus is apparent in animals challenged three or more days later; with an earlier challenge resistance seems to exist but the small numbers of animals permitted no statistically significant estimates. The vaccine, when effective, blocks the production of antibodies; observations have been made with EEE and JE viruses.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1974
- Accession Number
- AD0782906
Entities
People
- Jordi Casals-ariet
Organizations
- Yale University