 <unk> : During the 1940s the cause , method of communication and treatment of infectious <unk> was not well understood . <unk> began with COs working at psychiatric hospitals and was expanded to a major research project with 30 to 60 test subjects at the University of Pennsylvania and Yale University . The men were <unk> with infected blood plasma , swallowed nose and throat <unk> and the human body <unk> of infected patients , and drank contaminated water . 
