Ventilator-associated pneumonia (VAP) is a type of lung infection that occurs in people who are on breathing machines in hospitals. As such, VAP typically affects critically ill persons that are in an intensive care unit (ICU). VAP is a major source of increased illness, and death. Persons with VAP have increased lengths of ICU hospitalization and have up to a 20-30% death rate.The diagnosis of VAP varies among hospitals and providers but usually requires a new infiltrate on chest x-ray plus two or more other factors. These factors include temperature of >38 °C or 12 × 109/ml, purulent secretions from the airways in the lung, and/or reduction in gas exchange.