Mycobacterium avium-intracellulare is prevalent in AIDS patients. In an effort to determine the source of this infection, hospital water systems were sampled. The water contained chlorine. What is the usual method of transmission for Mycobacterium? What is the probable source of infection in hospitals? How can such nosocomial infections be prevented?

Percentage of samples with M. avium
Hot water	Cold water	
February	88%	February	22%
June	50%	June	11% 
Additional Requirements 

Level of Detail: Show all work 
Other Requirements: needs to be approximately 125 words