13 
or micronized microbial dry powder, and aerosol challenge of animals from 
mice to monkeys, is a demonstration that a combination of Class I cabinets 
and Class III gastight cabinets, together with all the usual secondary 
barriers, can reduce the number of, but cannot prevent, laboratory 
infections when highly infective organisms are handled as aerosols. This 
modern brick building, with 38,600 square feet of space, was completed in 
May, 1953. It contained 14 ventilated Class I steel cabinets 60 inches wide, 
and 5 steel 72-inch wide animal -transfer cabinets to use in conjunction with 
ventilated steel animal cages. There were more than 200 linear feet of 
Class III gastight cabinets, a pneumatic tube system to convey small animals 
from aerosol exposure chambers, of the Reyniers type, to the animal caging 
rooms, and a complex optical system to bring in sunlight to study the effect 
of its various wave lengths upon microbial aerosols. 
Infections were as follows: 1953 - 1 brucellosis; 1954 - 3 tularemia, 
2 Q fever; 1955 - 2 Q fever, 2 Venezuelan encephalitis (VEE); 1956 - 
2 tularemia; 1957 - 1 brucellosis, 1 VEE; 1958 - 3 tularemia, 1 cutaneous 
coccidioidomycosis from an accidental syringe inoculation; 1959-68 - no 
infections; 1969 - 2 nonhospital ized tularemia cases. 
An effective cell-free anthrax vaccine was introduced in 1952 and 
extended to craftsmen in July 1958. The introduction of live tularemia 
vaccine in June 1959, and live VEE vaccine in 1963 ended infection with 
those agents. 
The effectiveness of containment systems in Building 376 can be better 
appreciated with knowledge of the numbers of animals challenged with microbial 
aerosols, the etiologic agents under experimentation, and a realization of 
the amount of laboratory work preceding and following the aerosol izations . 
[384] 
