<prompt> Answer this question truthfullyCould you explain what hospital-acquired pneumonia means?  <response>: <reason> Hospital-acquired pneumonia HAP or nosocomial pneumonia refers to any pneumonia contracted by a patient in a hospital at least 4872 hours after being admitted. It is thus distinguished from community-acquired pneumonia. It is usually caused by a bacterial infection, rather than a virus. HAP is the second most common nosocomial infection after urinary tract infections and accounts for 1520 of the total. It is the most common cause of death among nosocomial infections and is the primary cause of death in intensive care units. HAP typically lengthens a hospital stay by 12 weeks. 