Respiratory Syncytial Virus Infection (RSV)

Respiratory Syncytial Virus (RSV) Overview

Respiratory syncytial (sin-SISH-uhl) virus, or RSV, is a respiratory virus that infects the lungs and breathing passages. Most otherwise healthy people recover from RSV infection in 1 to 2 weeks. However, infection can be severe in some people, such as certain infants, young children, and older adults. In fact, RSV is the most common cause of bronchiolitis (inflammation of the small airways in the lung) and pneumonia in children under 1 year of age in the United States. In addition, RSV is more often being recognized as an important cause of respiratory illness in older adults.

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Learn about Respiratory Syncytial Virus

RSV is the most common cause of bronchiolitis and pneumonia among infants and children under 1 year of age.

Respiratory syncytial virus (RSV) is a contagious viral disease that can lead to serious health problems—especially for young children and older adults.

About RSV

Clinical Information

Research & Surveillance

Fast Facts

Almost all children will be infected with RSV by their second birthday.
RSV causes respiratory illness in infants and young children, and is the most important cause of bronchiolitis.
In the U.S., RSV infections generally occur during fall, winter, and early spring.

Data and Statistics

Chart: Duration of RSV Season, by U.S. Department of Health and Human Services Region and Florida, July 2010- June 2011 (listed by region number, or state, and headquarter city in order from earliest to latest RSV season start date): Florida onset: mid-August 2011; offset: early March 2012. Region 3 (Philadelphia) onset: late October 2011; offset: late March 2012. Region 2 (New York) onset: mid-November 2011; offset: mid-March 2012. Region 6 (Dallas) onset: mid-November 2011; offset: late March 2012. Region 1 (Boston) onset: early December 2011; offset: early March 2012. Region 4 (Atlanta) onset: early December 2011; offset: late March 2012. Region 5 (Chicago) onset: early December 2011; offset: late April 2012. Region 9 (San Francisco) onset: mid-December 2011; offset: early May 2012. Region 10 (Seattle) onset: late December 2011; offset: late April 2012. Region 8 (Denver) onset: early January 2012; offset: mid-May 2012. Region 7 (Kansas City) onset: mid-January 2012; offset: mid-April 2012.

More Data & Statistics

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