Editor’s note: This blog was updated Oct. 26, 2023 to include the most recent RSV immunization information.
COVID-19, flu and respiratory syncytial virus (RSV) cases are being seen across the United States.
They’re all highly-contagious respiratory infections caused by viruses. These infections typically affect the lungs, airways, sinuses or throat. While they’re seen year-round, there’s often a significant increase during fall and winter when people tend to spend more time inside. This allows viruses to pass more easily between people. Dry, cold air allows viruses to survive longer and cause more illness.
The three can be difficult to tell apart because they share many symptoms. However, knowing the difference can help you best determine the course of treatment.
The viruses share similar symptoms
RSV symptoms typically mirror that of a common cold, including runny nose, fatigue, cough and sore throat. More serious infections can cause difficulty breathing or wheezing.
“RSV poses a serious threat to older adults, especially those with heart or lung disease,” said Dr. Edward Belongia, an infectious disease epidemiologist at Marshfield Clinic Research Institute. “It is well-known to cause breathing problems in infants, but we now know it also can cause serious illness in adults.”
People most vulnerable to severe RSV infection include infants, children with lung diseases, people ages 65 and older and people with weakened immune systems.
Both COVID and flu viruses can cause symptoms similar to RSV. This includes fever, chills, headache, cough, muscle aches, fatigue, shortness of breath, runny nose and sore throat. Doctors often rely on laboratory testing to identify the specific virus, since treatment options are different.
Seek medical care early if you have a high risk condition such as heart disease, lung disease or diabetes and if you have the flu or COVID. People with certain chronic diseases may have a higher risk of complications from the flu or COVID.
The best way to know for certain what virus is causing your symptoms is to get tested.
“Early testing is important if you might have COVID or the flu,” said Dr. Belongia. “Treatment is most effective when started soon after symptoms begin.”
Testing for COVID and the flu uses nasal swabs, but the tests are different.
If you have flu-like symptoms or know you have been exposed to COVID and need to be tested, contact your provider or the Health System 24-hour Nurse Line at 844-342-6276 that can provide screening information and schedule testing, if needed.
While there is no treatment for RSV, a test is available. Knowing whether you have RSV may affect the precautions you decide to take in your home, such as staying away from infants if you are sick.
Vaccines are available for COVID, flu and RSV
Immunizations were recently developed for RSV to provide needed protection against the dangerous virus. The Centers for Disease Control and Prevention (CDC) recommends immunizations for adults age 60 and older, pregnant women between 32-36 weeks pregnant and newborns and high-risk infants less than 19 months of age.* **
Vaccinations also are available to help prevent COVID-19 and influenza.
Health care providers can prescribe Paxlovid for some people with COVID, including those at a higher risk for severe illness. The treatment is for mild-to-moderate COVID in adults and children, 12 years and older, who have a positive test for COVID and who are at a high risk for progression to severe COVID, including hospitalization or death.
For those battling flu, there are treatments available to reduce the length of flu symptoms, including Tamiflu.
*Marshfield Clinic Health System and the nation is seeing shortages of the infant immunization. The maternal vaccination may be the preferred option to protect infants against RSV.
**Coverage for the RSV immunizations may change depending on your insurance carrier. You are encouraged to call your insurance carrier prior to making an appointment to receive your vaccine.