RSV is absolutely contagious to adults. While it’s best known as a childhood illness, respiratory syncytial virus infects people of all ages, and most adults catch it multiple times throughout their lives. For the majority of healthy adults, RSV feels like a bad cold. But for older adults and those with certain chronic conditions, it can progress to serious lower respiratory illness.
How RSV Spreads Between Adults
RSV spreads the same way most respiratory viruses do: through droplets released when an infected person coughs, sneezes, or talks. You can also pick it up by touching a contaminated surface and then touching your face. The virus enters through the eyes, nose, or mouth.
What makes RSV particularly easy to catch is the timeline. People become contagious a day or two before they show any symptoms, which means they can spread the virus without realizing they’re sick. Once symptoms appear, a person typically remains contagious for 3 to 8 days. During that window, close contact with an infected person (sharing a household, working in tight quarters, caring for a sick child) creates a clear path for transmission.
You Can Get RSV More Than Once
Unlike some viruses that grant long-lasting immunity after infection, RSV provides only short-lived, partial protection. A landmark study published in The Journal of Infectious Diseases tracked reinfection rates and found that within just over two years, 73% of participants had been infected at least twice and 47% had been infected three or more times. Even people with the highest levels of antibodies still had a 25% chance of reinfection when exposed again.
This means RSV isn’t a “one and done” virus. Your immune system does build some resistance after each infection, which tends to make subsequent bouts milder, but that protection fades relatively quickly. Adults who spend time around young children (parents, grandparents, daycare workers) are especially likely to catch it repeatedly because RSV circulates heavily in pediatric populations.
What RSV Feels Like in Adults
In most healthy adults, RSV produces symptoms that overlap heavily with the common cold: runny nose, sore throat, cough, mild headache, fatigue, and low-grade fever. This overlap is exactly why many adults never realize they’ve had RSV rather than a typical cold.
There are a few clues that can help you tell the difference. Wheezing, a whistling sound when you breathe, is a hallmark of RSV but uncommon with a standard cold. The trajectory of symptoms also matters. A cold tends to peak around day three or four and then gradually improve. With RSV, symptoms are more likely to worsen over time rather than steadily getting better. If you’re a week into what seemed like a cold and you’re feeling worse instead of recovering, RSV is a stronger possibility. A blood test or mouth swab can confirm the diagnosis if your doctor thinks it’s worth checking.
Who Faces the Greatest Risk
For a healthy 35-year-old, RSV is an unpleasant week. For certain adults, it can lead to pneumonia or bronchiolitis requiring hospitalization. The CDC identifies several groups at highest risk for severe illness:
- Adults 75 and older, whose immune response to respiratory infections naturally weakens with age
- Adults with chronic heart or lung disease, including heart failure, COPD, emphysema, and asthma
- Adults with weakened immune systems, whether from medication, cancer treatment, or an underlying condition
- Adults with severe obesity (BMI of 40 or higher)
- Adults with chronic kidney disease, liver disease, or diabetes that has caused organ damage
- Nursing home residents, where close living quarters and shared caregivers accelerate spread
If you fall into one of these categories, an RSV infection that starts with cold-like symptoms deserves closer attention, particularly if you develop difficulty breathing, a persistent high fever, or a bluish tint to your lips or fingernails.
RSV Vaccination for Adults
An RSV vaccine is now available for adults, and the CDC recommends a single dose for everyone 75 and older. Adults between 50 and 74 who have any of the high-risk conditions listed above are also recommended to get vaccinated. You don’t need medical records to prove you qualify. Simply telling your pharmacist or doctor that you have a qualifying condition is enough.
The vaccine is designed to reduce the risk of severe lower respiratory illness rather than prevent infection entirely, similar in concept to how flu vaccines work. For adults in the recommended groups, it offers meaningful protection during RSV season, which in most of the United States runs from fall through early spring.
Practical Ways to Reduce Transmission
Because RSV spreads so easily, especially before symptoms appear, prevention relies on the same basics that work against other respiratory viruses. Frequent handwashing with soap and water is the single most effective step, particularly after being in public spaces or around anyone who’s sick. Avoid touching your face with unwashed hands. If you’re the one who’s sick, coughing into your elbow and staying home during the most contagious days (the first few days of symptoms) limits how many people you expose.
Cleaning frequently touched surfaces matters too, since RSV can survive on hard surfaces for several hours. For adults caring for a sick child, this is especially relevant. Kids tend to spread RSV generously through drool, runny noses, and shared toys, making parents and grandparents the most common adult recipients of the virus.