Interference between human hepatitis A virus and an attenuated apathogenic avian virus.

The effect of an attenuated apathogenic avian bursa virus on the course of human hepatitis A viral infection was studied in marmoset monkeys. The monkeys were infected with human hepatitis A virus, then superinfected with avian bursa virus one and three weeks after initial inoculation with human hepatitis A virus. The superinfected monkeys did not show the characteristic serum glutamic pyruvic transaminase (SGPT) elevation. Also their liver biopsies showed no pathologic changes. The virus control animals exhibited six times higher SGPT enzyme elevation than the superinfected groups, and hepatitis was detected by histopathology. This experiment, as known to us, is the first in which a definite interference was documented using a nonpathogenic virus against a highly pathogenic and clinically significant human virus. This should be considered a successful experiment demonstrating that the use of an apathogenic virus for the cure of a virus-induced disease is a realistic possibility.