This article in the Journal of Public Health Policy determines the rates and costs of hospitalizations related to opportunistic premise plumbing pathogens. The authors found that between 1991 and 2006, more than 617,000 hospitalizations related to three common plumbing pathogens resulted in around $9 billion in Medicare payments - an average of $600 million a year. The costs may now exceed $2 billion for 80,000 cases per year.