Bacterial or viral infections of the respiratory tract
Viral illnesses are the most common cause of upper
respiratory symptoms. Symptoms of a viral illness often appear over several
hours without prior illness. Common viral illnesses include colds and the flu
Bacterial respiratory tract infections are less
common than viral infections. Bacterial infections may develop after a viral
illness such as a cold or the flu. Bacterial infections may affect the upper or
lower respiratory system, and symptoms tend to localize to one area.
Recommended Related to Lung Disease/Respiratory Problems
Your lungs work hard -- most adults take more than 20,000 breaths a day. But just how well your lungs do their job may be affected by the job you do.
Chemicals. Germs. Tobacco smoke and dirt. Fibers, dust, and even things you might not think are dangerous can damage your airway and threaten your lungs.
"The lungs are complex organs," Philip Harber, MD, MPH, professor of public health at the Mel and Enid Zuckerman College of Public Health at the University of Arizona in Tucson, tells WebMD. "Occupational...