ABSTRACT
Acute lower respiratory tract infections include tracheobronchitis and pneumonia. More than 10 million office visits for bronchitis are made annually in the United States. Twothirds of these cases are treated with antibiotics, accounting for at least 10% of all out patient antibiotic prescriptions. There are approximately 4 million cases of communityacquired pneumonia in the United States each year, leading to more than 500,000 hospital admissions. Pneumonia is the sixth leading cause of death in the United States and results in more fatalities than any other infection. The estimated economic burden of pneumonia exceeds $20 billion per year in direct treatment costs and loss of wages.
