It's long been feared that computer viruses or malware would someday disrupt critical infrastructure like hospitals.  And it looks like it's finally happened. According to an Atlanta Journal-Constitution article on Dec. 9, the Gwinnett Medical Center in Gwinnett County, Ga., had to divert patients to other hospitals after a system-wide virus shut down patient registration at its campuses in Lawrenceville and Duluth.  The effects were felt throughout the system for all of last weekend. According to the article, “the infection, an ‘I.T. service interruption virus,’ has affected systems intermittently.”  Like other businesses that rely on computers, viruses frequently occur in hospitals, but this is the first reported incident in which a virus had such a widespread effect on an entire hospital system. Computer-security experts at a number of information-assurance companies in Silicon Valley are paying careful attention to the incident, and how this latest virus has affected Gwinnett and its patients.