Respiratory Syncytial Virus (RSV), a common virus spread through close contact with an infected person coughing and sneezing, or touching objects such as toys or door knobs that have the virus on them.

Already, RSV is so common that nearly 100% of children are infected with the virus by age two. Most people, including infants, develop only mild symptoms similar to that of a common cold, but for some it can be severe and even life threatening. 

Dr. Juanita Mora, a leading U.S. allergist and American Lung Association Spokesperson talked with KRLD's John Liddle about why experts are concerned that RSV could return to pre-pandemic levels.

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