RSV in older adults typically starts with mild, cold-like symptoms: cough, stuffy or runny nose, fever, and decreased appetite. That’s the full list for many people, and it can look so ordinary that RSV often goes unrecognized. But in adults over 65, the virus carries real risk. During the 2022-2023 season alone, an estimated 93,000 adults aged 65 and older were hospitalized with RSV in the United States, and roughly 5,500 of them died in the hospital.
Early Symptoms That Resemble a Cold
After exposure to the virus, symptoms typically appear within 3 to 5 days. The initial phase looks like any upper respiratory infection: a runny or stuffy nose, a persistent cough, low-grade fever, and reduced appetite. You might also feel generally run down. At this stage, there’s nothing distinctive about RSV compared to a dozen other viruses circulating in fall and winter.
Most healthy adults clear the infection within one to two weeks. But in older adults, particularly those over 75, the virus is more likely to move deeper into the lungs and become something more serious.
When Symptoms Move to the Lungs
The shift from a mild upper respiratory infection to a lower respiratory tract illness is the key danger with RSV in older adults. When the virus reaches the smaller airways and lung tissue, it can cause bronchiolitis (inflammation of the small airways) or pneumonia. Signs that the infection is progressing include:
- Wheezing or audible rattling when breathing
- Shortness of breath, especially with minimal activity or at rest
- Rapid, shallow breathing
- Worsening cough that becomes deeper or more frequent
- Visible effort to breathe, such as flaring nostrils or using chest and neck muscles
- Bluish tint around the lips or fingernails, signaling low oxygen
These symptoms can develop gradually over several days. In some cases, what starts as sniffles and fatigue escalates into a medical emergency within a week. Adults aged 75 and older face the steepest risk: they accounted for nearly 59,000 hospitalizations and close to 4,000 in-hospital deaths during the 2022-2023 RSV season, roughly double the numbers seen in the 65-to-74 age group.
How RSV Worsens Existing Conditions
One reason RSV is so dangerous in older adults is that it doesn’t just cause its own set of symptoms. It can destabilize chronic conditions that were previously well managed. In people with COPD, RSV often triggers what looks like an acute flare-up: worsening shortness of breath, increased sputum production, and more frequent or severe coughing. In people with congestive heart failure, RSV can push the heart into decompensation, causing fluid buildup in the lungs, swelling in the legs, rapid heart rate, and sudden weight gain from retained fluid.
In both situations, the underlying viral infection may go completely unrecognized. The patient and their doctors may attribute everything to a COPD exacerbation or heart failure flare, never testing for RSV. This means the true burden of RSV in older adults is likely underestimated.
How RSV Differs From Flu and COVID-19
All three viruses cause cough, fever, and congestion, which is why they’re so easy to confuse. But there are patterns that can help you tell them apart.
Flu tends to hit suddenly and hard. Body aches, chills, headache, and fatigue are prominent from the start, often before respiratory symptoms fully develop. RSV, by contrast, tends to be more gradually respiratory in nature. Cough and nasal congestion dominate, while body aches and headaches are less common. COVID-19 has the broadest symptom profile of the three, potentially including loss of smell or taste, gastrointestinal symptoms like nausea and diarrhea, and a longer incubation period of 2 to 14 days compared to RSV’s 3 to 5 days or the flu’s 1 to 4.
None of these patterns are reliable enough for a definitive answer on their own. Testing is the only way to confirm which virus you’re dealing with, and many clinics now offer combination tests that check for all three at once.
Who Faces the Highest Risk
Not every older adult faces equal risk from RSV. The people most likely to develop severe illness include those over 75, adults with chronic lung disease like COPD or asthma, those with congestive heart failure, people with weakened immune systems (from cancer treatment, organ transplant, or other causes), and residents of nursing homes or long-term care facilities where the virus spreads easily in close quarters.
If you fall into any of these categories, even a mild cold during RSV season (typically late fall through early spring) deserves closer attention than you might normally give it.
Vaccination Reduces Severe Illness
RSV vaccines approved for adults 60 and older have shown strong protection against the kind of severe lower respiratory illness that leads to hospitalization. A meta-analysis of clinical trials found that vaccination reduced the risk of lower respiratory tract disease by about 81% during the first RSV season after the shot. Protection does decrease over time, dropping to around 61% by the second season, but that still represents meaningful protection against the most dangerous outcomes.
The vaccines don’t necessarily prevent you from catching RSV or developing mild cold symptoms. Their primary value is in keeping a routine infection from becoming a life-threatening one.
Warning Signs That Need Immediate Attention
If you or someone you’re caring for has RSV symptoms and develops any of the following, seek medical care promptly: difficulty breathing or shortness of breath that’s getting worse, a bluish color to the lips or face, confusion or unusual drowsiness (which can signal low oxygen levels), inability to keep fluids down, or symptoms that improve and then return worse than before. That last pattern, a brief improvement followed by rapid decline, can indicate a secondary bacterial infection like pneumonia developing on top of the viral illness.