Pregnancy abnormalities among personnel at a virological laboratory

Observations on an increased spontaneous abortion rate initiated a study among personnel working at a laboratory for diagnostic virology. Personnel at a bacteriological laboratory and at another virological laboratory served as controls. Seventy-seven female employees at the laboratory for virology were interviewed, as well as 91 at the bacteriology laboratory and 45 women at another virological laboratory. A significantly increased perinatal death rate was found among the virology personnel, with no apparent clustering over the time period studied. A higher serum titer against common viruses was found among employees actively working with patient sera. A model experiment demonstrated the risk for aerosolization of serum samples during processing. No evidence of a relationship between chemical work environment factors and the increased perinatal death rate was found. It is concluded that the factor in the working environment most closely related to the increased perinatal death rate was exposure to viral aerosols.