The U.S. Centers for Disease Control and Prevention (CDC) recently issued a health advisory warning about an unusual, sharp increase in the number of respiratory syncytial virus (RSV) cases this summer, particularly across southern states. With this reported increase, the agency calls for more widespread RSV testing in those with respiratory symptoms but a negative COVID-19 test.

RSV is a very common and contagious respiratory virus that spreads easily from person to person through coughing, sneezing, and touching contaminated surfaces. The virus is so pervasive that nearly all children have been exposed to it by the time they are 2 years old.

Normally, RSV is seasonal in the U.S., with outbreaks occurring in the fall and winter, and decreasing in early spring. This year, however, the CDC has observed an increasing number of reported cases since late March across several states, including Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, New Mexico, North Carolina, Oklahoma, South Carolina, Tennessee, and Texas. Since these outbreaks are not following the typical seasonal pattern, it is not possible to predict how long the outbreaks will continue or where they will occur, notes the CDC.

This unusual, out-of-season jump in cases is likely due to Americans self-isolating last fall and winter during the COVID-19 pandemic. Fewer people were exposed to RSV but now are contracting the virus as they go back to workplaces and schools, and begin to socialize again. With the virus spreading more easily now, infants who were not exposed during the fall and winter months are getting the infection as toddlers and as older children.

The recent health advisory also reminds individuals to stay home and away from others if they feel ill, even if they have a negative COVID-19 test. Taking other precautions, such as washing hands frequently, covering coughs and sneezes, and disinfecting surfaces, also helps limit the spread of RSV, especially to those who are most vulnerable.

While many adults show no symptoms and most people recover from an RSV infection without specific treatment, the illness can be serious in infants, young children, and the elderly.

  • In the U.S., RSV is the most common cause of pneumonia and bronchiolitis (inflammation and congestion of the lung’s small airways) in children less than a year old.
  • Each year, about 58,000 children younger than age 5 are hospitalized due to RSV, and there are roughly 100-500 deaths in this age group.
  • In adults aged 65 and older, RSV leads to about 177,000 hospitalizations and 14,000 deaths.

Other people at high risk for a severe RSV infection include those with weakened immune systems or long-term conditions, such as chronic lung and heart disease, and the illness can cause the condition to worsen. For instance, RSV infections may trigger more frequent attacks in those with asthma or may aggravate symptoms such as shortness of breath, heart palpitations, and rapid pulse in people with congestive heart failure.

With this alert, healthcare providers and caregivers can be more vigilant for symptoms of RSV during the coming summer months. Common symptoms include runny nose, sneezing, coughing, which can progress to wheezing, and fever. Infants with RSV may also show fussiness, poor feeding, and pauses while breathing (apnea). Seek immediate medical care for any child–or for anyone–who experiences severe symptoms such as difficulty breathing, high fever, and/or bluish skin, lips or nail beds.

Since RSV symptoms can overlap with those of COVID-19 and other respiratory illnesses, testing for RSV can help establish a diagnosis. Knowing which virus is causing the illness can help guide treatment. Those at high risk can be monitored closely and may be hospitalized if symptoms worsen. Infants and young children at high risk of severe RSV illness may be given medication that can help to lower that risk.

While no vaccine is available yet to protect against RSV, scientists are currently working to develop one.


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