Wednesday, May 22, 2013

Colds and the Flu - Introduction

Table of Contents

Introduction


Upper respiratory tract infections affect the air passages in the nose, ears, and throat.

Throat anatomy
Structures of the throat include the esophagus, trachea, epiglottis, and tonsils.

Structures of the throat include the esophagus, trachea, epiglottis, and tonsils.

The infections can be caused by viruses, bacteria, or other microscopic organisms. In most cases, these infections lead to colds or mild influenza (flu) and are temporary and harmless. In rare cases, flu can be severe, or the infections may turn into pneumonia.

Organisms that cause these upper respiratory tract infections are generally spread by:

  • Direct contact (such as hand-to-mouth)
  • Coughing or sneezing

Review Date: 01/29/2011
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)