Symptoms

Signs and symptoms of respiratory syncytial virus infection most commonly appear about four to six days after exposure to the virus. In adults and older children, RSV usually causes mild cold-like signs and symptoms. These may include:

• Congested or runny nose
• Dry cough
• Low-grade fever
• Sore throat
• Sneezing
• Headache

In severe cases

RSV infection can spread to the lower respiratory tract, causing pneumonia or bronchiolitis — inflammation of the small airway passages entering the lungs. Signs and symptoms may include:

• Fever
• Severe cough
• Wheezing — a high-pitched noise that's usually heard on breathing out (exhaling)
• Rapid breathing or difficulty breathing — the person may prefer to sit up rather than lie down
• Bluish color of the skin due to lack of oxygen (cyanosis)

Infants are most severely affected by RSV. Signs and symptoms of severe RSV infection in infants include:

• Short, shallow and rapid breathing
• Struggling to breathe — chest muscles and skin pull inward with each breath
• Cough
• Poor feeding
• Unusual tiredness (lethargy)
• Irritability

Most children and adults recover in one to two weeks, although some might have repeated wheezing. Severe or life-threatening infection requiring a hospital stay may occur in premature infants or in anyone who has chronic heart or lung problems.

RSV and COVID-19

Because RSV and coronavirus disease 2019 (COVID-19) are both types of respiratory viruses, some symptoms of RSV and COVID-19 can be similar. In children, COVID-19 often results in mild symptoms such as fever, runny nose and cough. For adults with COVID-19, symptoms may be more severe and may include trouble breathing.

Having RSV may lower immunity and increase the risk of getting COVID-19 — for kids and adults. And these infections may occur together, which can worsen the severity of COVID-19 illness.

If you have symptoms of a respiratory illness, your doctor may recommend testing for COVID-19.

When to see a doctor

Seek immediate medical attention if your child — or anyone at risk of severe RSV infection — has difficulty breathing, a high fever, or a blue color to the skin, particularly on the lips and in the nail beds.