Airborne transmission of polyoma virus.

Polyoma virus (PV) infection was transmitted through the air of an animal laboratory. Mice free of detectable antibodies to PV were exposed for 1 month to the airborne environment of laboratories housing naturally infected mice. The seroconversion rate was 75% (24/32), as measured by hemagglutination inhibition. Control mice, housed in the sterile atmosphere of a mass air flow cabinet (MAFC) in the same laboratory, had a seroconversion rate of 15.8% (3/19). Airborne transmission occurred bia PV aerosois, generated by the handling of contaminated bedding, cages, and mice during weekly housekeeping. Length of exposure to PV aerosols correlated with seroconversion. One- and 3-hour exposures resulted in seroconversion rates of 40% (6/15) and 72% (23/32), respectively. Seroconversion rates of mice continuously housed in MAFC totaled 5% (2/40). Checkerboarding mice free of detectable antibodies with mice given 10(5) mean tissue culture infective doses of PV ip resulted in an airborne infection rate of 50% (15/30) in a conventionally ventilated room during a 12-week study. The airborne transmission rate was 10% (3/30) when experiments were performed in a mass air flow room with a vertical air velocity of 30 feet/minute was used. Antibodies to PV could not be detected in any of 138 human sera, including sera from 29 animal-care technicians who handled PV-infected mice and 15 personnel who had worked with the virus.