2 
no precautions in the handling of air, sewage, refuse, laundry, or access to 
the laboratory. The ventilated safety cabinet, which is the principal safety 
device to protect the laboratory worker from exposures to infectious agents, 
was not commercially available until 1950. It also is significant that the 
National Institutes of Health did not have a research laboratory specifically 
designed to provide safe conditions for research with infectious agents until 
1947 (2). 
Nevertheless, it has not been possible to find reports of laboratory- 
attributed infection in persons who never were in the laboratory building or 
who were not associated in some way with the laboratory. Reports of infection 
by association include (1) Q fever from unsterilized laboratory clothing in 
six employees in a commercial laundry (3), (2) two persons involved in 
laundry, cleaning, and contact with a technician in a rooming house during 
a laboratory outbreak of Q fever (3), (4) Q fever in a switchboard operator 
in a nearby building - extent of contact with laboratory personnel is unknown 
(5), (4) Q fever in a wife whose husband was believed not to have taken the 
required shower before going home (6), (5) facial anthrax lesion in the wife 
of a bacteriologist during a time (January 1946) when there were several 
laboratory cutaneous infections (6,7), and (6) nine hospitalized and 26 non- 
hospital ized cases of Q fever in employees of a rendering plant that processed 
Q fever-infected guinea pig carcasses from a laboratory (8). No other 
laboratory-associated cases were found, although there are a few instances 
of a wife becoming infected after her husband contracted an occupational 
illness, and several infections of visitors. 
The preponderance of Q fever reflects the unusual stability of the 
etiologic agent and the small amount required to infect man (1 to 10 micro- 
organisms), although the same low human infective dosage also applies to the 
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