Accession Number:

ADA099273

Title:

Respiratory Tularemia: Comparison of Selected Routes of Vaccination in Fischer 344 Rats,

Descriptive Note:

Corporate Author:

ARMY MEDICAL RESEARCH INST OF INFECTIOUS DISEASES FREDERICK MD

Personal Author(s):

Report Date:

1981-05-08

Pagination or Media Count:

28.0

Abstract:

Fischer 344 rats were given attenuated live vaccine strain LVS of Francisella tularensis by small particle aerosol, intranasal i.n. instillation, or by intraperitoneal i.p., intramuscular i.m., or subcutaneous s.c. injection. All of the vaccinated rats developed subclinical infection by 3 days after exposure, which cleared by day 28. Temporal patterns and concentrations of the LVS organisms within the hosts were dependent upon the route a vaccination. Pathologic alterations were limited to minimal lung lesions in aerosol vaccinated rats and mild splenitis in i.p. vaccinated rats. Agglutinins to LVS were detected in the serum of each vaccinated animal and in the brochoalveolor wash fluids of 66 of the aerosol-vaccinated rats. The agglutinins appeared to be exclusively of the immunoglobulin M class. Regardless of route of vaccine administration, all vaccinated rats survived an aerosol challenge of 5.3 log10 cells of virulent F. tularensis while all non-vaccinated rats died. Systemic infection did not occur in the vaccinated rats. Pulmonary infection, however, was not prevented in the vaccinated rats following aerosol challenge, but proliferation of the virulent F. tularensis organisms in the lungs was significantly lower P less than or equal to 0.01, analysis of variance than that which occurred in the control animals. These studies demonstrate the utility of the inbred Fischer 344 rat as a model for further investigations of F. tularensis infection and its associated immune response. Author

Subject Categories:

  • Medicine and Medical Research

Distribution Statement:

APPROVED FOR PUBLIC RELEASE