Communicable Diseases and Public Health: Viruses, Bacteria, and Parasites This web-based case study describes four public health scenarios featuring communicable diseases: norovirus, Methicillin-resistant Staphylococcus aureus (MRSA). meningococcal meningitis, and gastroenteritis. Each case study presents information on disease causes, symptoms, transmission, treatment, prognosis, and prevention. The case study is broken down into six modules: 1) Introduction; 2) Nursing Home Malaise; 3) A Rash of Team Infections; 4) After-School Illness; 5) Retreat from Health; and 6) Conclusion. (2005) Audience: General Public Health Format(s): Web-based