RSV (respiratory syncytial virus) is not the common cold, but it often looks exactly like one. In healthy adults, RSV typically causes the same runny nose, sore throat, headache, and low-grade fever you’d expect from any cold virus. The difference is what RSV can do when it moves deeper into the lungs, especially in babies, older adults, and people with chronic health conditions.
The confusion makes sense. The “common cold” isn’t one virus. It’s a label for mild upper respiratory infections caused by over 200 different viruses. Rhinovirus is the most frequent culprit, but RSV, adenovirus, and others all cause colds too. So RSV can absolutely give you a cold. The problem is that it doesn’t always stop there.
How RSV and a Typical Cold Overlap
In healthy adults and older children, RSV and rhinovirus infections can be clinically indistinguishable. Both produce congestion, coughing, a sore throat, and general fatigue. Both typically resolve in one to two weeks without treatment. A study comparing the two viruses in young children found their clinical features “may be indistinguishable” based on symptoms alone, and the same holds true for adults with healthy immune systems.
This is why most people who get RSV never know it. They assume they caught a cold, ride it out, and move on. For the majority of infections, that’s a perfectly fine outcome.
Three Signs It Might Be RSV, Not a Cold
While most RSV infections feel like a standard cold, a few patterns can hint that RSV is the cause rather than rhinovirus or another mild virus.
- Wheezing. A whistling sound when you breathe is a hallmark of RSV. It happens because the virus inflames the smaller airways in your lungs. Wheezing is uncommon with a typical cold.
- Symptoms that worsen instead of improving. Colds generally peak around day three or four and then gradually improve. With RSV, symptoms sometimes intensify over the first week rather than fading.
- A persistent or worsening cough with chest tightness. Because RSV tends to affect the lower respiratory tract more aggressively than rhinovirus, coughing can feel deeper and more forceful.
A blood test or mouth swab can confirm RSV. PCR-based tests are highly sensitive and can diagnose RSV in anyone. Rapid antigen tests are also available and give quicker results, though they’re slightly less accurate. Doctors typically order testing only when symptoms aren’t improving or when someone is at higher risk for complications.
Why RSV Is More Dangerous Than a Cold
The real distinction between RSV and a garden-variety cold isn’t the sniffles. It’s how often RSV progresses to serious lower respiratory infections like bronchiolitis (inflammation of the small airways) and pneumonia. Among babies and toddlers under age 2 who catch RSV for the first time, up to 40% develop one of these complications. By contrast, rhinovirus infections in young children are mild about 73% of the time, while only about 30% of RSV cases in infants stay mild.
Hospitalization data reinforces the gap. In the 2024-25 RSV season, roughly 8.5 out of every 1,000 infants under 8 months old were hospitalized with confirmed RSV. For children aged 8 to 19 months, the rate was about 10.6 per 1,000. These numbers actually represent a significant drop from pre-pandemic seasons, likely due to new preventive treatments, but they still reflect a virus that regularly sends thousands of young children to the hospital each year.
Older adults face their own risks. RSV can trigger dangerous flare-ups of chronic lung disease, heart failure, and asthma. Adults with weakened immune systems are particularly vulnerable.
How RSV Spreads
RSV spreads the same way colds do: through respiratory droplets from coughs and sneezes, direct contact like kissing or handshakes, and touching contaminated surfaces then touching your face. People with RSV are usually contagious for 3 to 8 days and can start spreading the virus a day or two before symptoms appear. Infants and immunocompromised individuals can shed the virus for 4 weeks or longer, even after they feel better.
Treatment Is the Same as a Cold (Usually)
There’s no antiviral medication routinely used for RSV. Like a cold, most infections resolve on their own within one to two weeks. The treatment approach is identical to what you’d do for any respiratory virus: manage fever and pain with acetaminophen or ibuprofen, stay hydrated, and rest. Never give aspirin to children.
The difference comes when RSV moves into the lungs. Babies who develop bronchiolitis may need supplemental oxygen or IV fluids in a hospital. People with asthma or chronic lung disease may need treatment for flare-ups triggered by the infection. For most healthy adults, though, the recovery experience is no different from getting over a cold.
Who Should Get an RSV Vaccine
Unlike the common cold, RSV now has vaccines. The CDC recommends a single dose of RSV vaccine for all adults 75 and older, and for adults aged 50 to 74 who have conditions that raise their risk of severe illness. Those conditions include chronic heart disease, chronic lung disease, severe obesity (BMI of 40 or higher), diabetes with organ damage, weakened immune systems, and residence in a nursing home.
Three vaccines are currently available for adults 50 and older, with no preference among them. The vaccine works best when given in late summer or early fall, before RSV season peaks. It’s a one-time dose, not an annual shot.
For infants, preventive antibody treatments given either to babies directly or to pregnant mothers during the third trimester have helped cut hospitalization rates nearly in half compared to pre-pandemic seasons.
Warning Signs in Babies and Young Children
Because RSV starts out looking like a cold, parents often wonder when to worry. The key signals are difficulty breathing, visible effort to pull air in (you may see the skin between the ribs pulling inward with each breath), and refusal to drink fluids. In very young infants under 6 months, RSV can cause apnea, which is pauses in breathing lasting more than 10 seconds. Any of these signs warrants immediate medical attention.
Symptoms that get worse rather than better after the first few days are also a red flag, particularly in children under 2 who haven’t had RSV before.