Most people think RSV is something babies get. It is, and it is also one of the more common reasons older adults end up in a hospital bed each winter.
The problem is that in adults it looks like a cold for the first few days, so it is rarely taken seriously until it stops looking like one.
What are RSV symptoms in adults?
A runny nose, sore throat, cough, congestion, headache and tiredness, usually appearing gradually over a few days rather than all at once. In a healthy adult that is often the whole illness. What makes RSV different from an ordinary cold is that it can move downward into the lower airways, and that is when wheezing, chest tightness and breathlessness appear.
Fever is common but often mild, and plenty of adults never run one at all. That absence is part of why it gets dismissed.
How is RSV different from a cold?
For the first three days, barely at all. The difference shows up in where the infection settles. A cold stays in the nose and throat. RSV can reach the small airways in the lungs, and once it does, breathing becomes part of the picture.
Three things make RSV more likely than a plain cold: wheezing, a cough that is getting worse rather than better after day four, and breathlessness doing something as ordinary as climbing the stairs. None of those belong to a head cold.
Flu is a different comparison. Flu normally arrives fast and hits hard within hours, and knowing how long the flu stays contagious helps when you are trying to tell them apart. RSV builds slowly, which is exactly why it gets underestimated.
RSV, a cold and flu side by side
The three overlap enough that no single symptom separates them. The pattern does.
| Common cold | RSV in an adult | Flu | |
| How it starts | Gradual, over 1 to 2 days | Gradual, over 2 to 3 days | Sudden, often within hours |
| Fever | Rare, mild if present | Often mild or absent | Common and usually high |
| Body aches | Mild | Mild | Prominent, often severe |
| Wheezing | No | Common once it moves lower | Uncommon |
| Breathlessness | No | Possible from day 4 onward | Only if complications set in |
| Typical length | 5 to 7 days | 1 to 2 weeks | 3 to 7 days, cough longer |
When should an adult with RSV go to the ER?
Most adults with RSV never need one. For a healthy person under sixty it behaves like a heavy cold and clears on its own. The reason to pay attention is that RSV is one of the few colds that can move down into the lungs, and when it does the change is usually noticeable.
Come in for shortness of breath at rest, new or worsening wheeze, chest pain or tightness, lips or fingertips turning bluish or grey, or confusion, which in an older adult is often the first visible sign that oxygen levels have dropped.
Two more. If you have a lung or heart condition and your usual management is no longer holding it steady, do not wait to see whether it settles. And if you started improving and then turned a corner the wrong way, that often means a second infection has arrived on top of the first.
If you do come in, we check oxygen levels, take a chest X-ray and run blood work on site, which is what distinguishes RSV running its course from RSV that has become pneumonia treatment. Arlington ER is open 24 hours and takes walk-ins, which matters because this tends to turn in the evening.
Who is actually at risk from RSV?
Healthy adults under sixty usually get a bad cold and nothing more. The risk concentrates in specific groups, and it concentrates sharply.
- Adults over 60, where the risk climbs with each decade
- Anyone with asthma, COPD or another long-term lung condition
- Anyone with heart failure or coronary artery disease
- People whose immune system is suppressed by illness or treatment
- Adults living in long-term care, where it spreads quickly
For someone with existing lung or heart disease, the danger is less about RSV itself and more about what it does to the condition they already have. A chest infection on top of COPD or heart failure can destabilize something that was previously under control, and that is the usual route to a hospital admission.
How long does RSV last in adults?
Typically one to two weeks. The first few days resemble a cold, symptoms often peak around days three to five, and improvement follows through the second week. The cough is the last thing to leave, and like bronchitis treatment it can persist for several weeks after the infection has cleared.
Watch day four onward. If the trajectory flattens or reverses when it should be improving, that is the point at which RSV in an adult tends to become a problem.
Is RSV contagious between adults?
Very. It spreads through droplets from coughs and sneezes and through contaminated surfaces, and adults pass it to each other as readily as children do. People are generally infectious for three to eight days, starting a day or two before symptoms, though those with weakened immune systems can shed it for considerably longer.
The usual chain in a family is a child bringing it home with mild symptoms and passing it to a grandparent for whom it is a far more serious illness.
Frequently Asked Questions
Easily, and it is the most common way adults get it. A child with what looks like a minor cold can pass it to an adult for whom it turns into a chest infection, which is why it matters most in households with both young children and older relatives.
Yes. Immunity after infection is partial and short-lived, so reinfection in later seasons is normal. Repeat infections are often milder, though that is not guaranteed for anyone in a higher-risk group.
There is, and it is a swab similar to a flu or COVID test. It is most useful when the result would change what happens next, which is usually in older adults or people with lung disease rather than in otherwise healthy patients.
It can. The infection moves from the upper airways into the lungs, and that is more likely in older adults and people with existing lung disease. A returning fever and new breathlessness after a few days of improvement is the pattern to watch for.
In most of the United States it runs from autumn through early spring, overlapping with flu, which is part of why the two get confused. The CDC tracks seasonal activity, and MedlinePlus covers the basics.
