Respiratory syncytial virus (RSV) is a common virus that causes acute respiratory infection, ranging from the common cold to more serious illness.

Symptoms of RSV are similar to flu and COVID-19:

RSV Symptoms

• Fever
• Cough
• Congestion (runny nose)
• Sneezing
• Wheezing
• Decrease in appetite

For very young infants with RSV, the main symptoms may be:

• Irritability
• Less activity
• Difficulty breathing

Flu Symptoms

• Fever and/or chills
• Cough
• Congestion (runny or stuffy nose)
• Sore throat
• Body aches or muscle pain
• Headache
• Tiredness (fatigue)
• Gastrointestinal symptoms like nausea, vomiting or diarrhea (more common in children than adults)

COVID-19 Symptoms

• Shortness of breath or difficulty breathing
• Fever and/or chills
• Cough
• Congestion (runny or stuffy nose)
• Sore throat
• Muscle or body aches
• Headache
• Tiredness (fatigue)
• Gastrointestinal symptoms like nausea, vomiting or diarrhea
• New loss of taste or smell

Because there is overlap between the symptoms of RSV, COVID-19 and flu, the only way to know if you have RSV is to get tested for the virus that causes RSV. If you have symptoms of RSV, flu or COVID-19, talk to your primary care clinician about testing.

Who Is At Risk for RSV

Infants and older adults are at the greatest risk for severe illness and complications from RSV, including hospitalization.

According to the Centers for Disease Control and Prevention (CDC), in children in the U.S. who are under the age of 1, RSV is the most common cause for bronchiolitis and pneumonia. These infections of the lungs can cause severe inflammation. If your child is at high risk for serious RSV illness and under the age of 2, they may qualify for a monthly antibody injection to help prevent RSV. Talk to your child’s physician if you have questions.

Adults can get RSV, but they typically have mild symptoms and recover in a week or two.

— Northwestern Medicine Internal Medicine/Pediatrics Physician Alin K. Abraham, MD