Respiratory syncytial virus (RSV) is a common germ that can infect the nose, throat, lungs, and breathing passages.

For most healthy children and adults, RSV can result in mild, cold-like symptoms. But RSV can be serious and even life-threatening to babies, seniors, and people with weakened immune systems or underlying lung or heart disease.

Though many people have never heard of this virus, “RSV is so common that pretty much everyone gets it by the time they are 2 years old,” says Denise McCulloch, MD, MPH, an infectious disease physician-scientist at the University of Washington School of Medicine in Seattle.

RSV circulates in most parts of the country from November to April — the so-called “RSV season” — and typically peaks in January and February. But the arrival of COVID-19 in 2020 upended RSV’s usual pattern.

• Runny nose
• Congestion
• Mild headache
• Sore throat
• Cough
• Fever
• Tiredness

Symptoms generally last three to seven days, though a cough can linger for a couple of weeks.

Contact your doctor right away if your baby or child:

• Has breathing difficulty
• Is irritable and cannot or will not take a bottle or breast
• Is younger than 3 months old and has a fever
• Shows signs of dehydration, such as a dry mouth, crying without tears, and less frequent urination (fewer wet diapers)

RSV spreads easily. When someone who is infected coughs or sneezes, virus-containing droplets become airborne. “If you’re standing within six feet of that person, the virus can enter your body through your eyes, nose, or mouth,” says Dr. Michaels.

You can also get RSV by touching something an infected person touched, such as a doorknob or a toy, then touching your eyes, nose, or mouth. The virus can last on hard surfaces for many hours.

Virtually everyone gets RSV at least once and sometimes more than once. “Because you don’t develop a perfect immune response, you can get reinfected,” Michaels notes. “The first infection, however, is usually the worst.”

Young children who attend childcare centers or who have siblings in school are at a higher risk of exposure and infection. When kids bring RSV home, parents often get it, too. “For adults, it’s usually no big deal,” says Michaels. “You have a cold, and you don’t really know it’s different from any other viral infection. That’s because our airways are bigger, and we’ve seen it before.”

But for some babies, children, and adults, RSV can lead to serious lung infection, breathing problems, and hospitalization. “Infants are particularly vulnerable to severe RSV infection in the first two months of life,” Dr. McCulloch notes. Other people who are at risk for developing severe or life-threatening RSV include:

• Premature infants
• Young children born with heart or lung disease
• Children or adults with weakened immune systems due to diseases like cancer or treatments like chemotherapy
• Children who have neuromuscular disorders, such as muscular dystrophy
• Adults with heart or lung disease
• Older adults, especially those age 65 and up

Your doctor may suspect RSV based on symptoms and the amount of RSV currently circulating in your community.

To make a definitive diagnosis and rule out other respiratory illnesses like the common cold, the flu, or COVID-19, your doctor may order an antigen (rapid) test or a PCR (polymerase chain reaction) test for RSV.

If more severe illness is suspected, your doctor may order imaging tests, such as a chest X-ray or computerized tomography (CT) scan to check the lungs for signs of infection.

For at-home testing, the U.S. Food and Drug Administration (FDA) has authorized a kit from Labcorp that lets people determine whether they have RSV, COVID-19, or flu by swabbing their noses and sending the sample to a lab for PCR analysis.

Prognosis of RSV

Doctors do not routinely prescribe medication for RSV, although immunocompromised patients may receive the antiviral drug ribavirin or intravenous immunoglobulin.

But if you are sick or are caring for another adult or a child who is infected, there are some RSV home remedies that can ease discomfort:

• For adults, encourage drinking by keeping a supply of water at the bedside. For a baby with RSV, continue nursing or bottle-feeding as usual; suction their noses first to help with breathing.
• Try using a cool-mist vaporizer to soothe dry nasal passages (be sure to keep the device clean to prevent the growth of bacteria or mold).
• Apply saline nasal drops to help loosen mucus.
• Adults with fever and children older than six months can take an over-the-counter pain and fever reducer, such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin). Never give aspirin to children as it has been linked to a very rare but dangerous condition called Reye’s syndrome.

There are a number of steps you can take to reduce your risk of getting and spreading RSV.

During RSV season (or whenever RSV is circulating at especially high levels in your community), be sure to:

• Wash your hands frequently (for at least 20 seconds), and teach kids the importance of hand-washing. If soap and water isn’t available, use sanitizer with at least 60 percent alcohol.
• Avoid touching your eyes, nose, and mouth, and encourage kids to avoid doing this as well.
• Avoid close contact with those who are sick.
• Don’t share or allow kids to share cups, toys, or bottles.
• Clean high-touch surfaces like doorknobs and countertops with virus-killing disinfectant.
• Don’t smoke, and avoid exposure to secondhand smoke. Babies who are exposed to tobacco smoke (even from close contact with a smoker’s clothing) have a higher risk of getting severe RSV, Michaels notes.
• Consider wearing a face mask when around people you don’t live with, especially in indoor public areas.

For infants at high risk of severe RSV, including babies born prematurely or who have congenital lung disease or heart defects, doctors use a protective medication called Synagis (palivizumab), which is a monoclonal antibody (an immune system protein that is created in the lab). The drug, which is given as a monthly injection for five months, can help prevent severe RSV infection.

The U.S. Food and Drug Administration (FDA) also recently approved the monoclonal antibody drug Beyfortus (nirsevimab) for babies born during or entering their first RSV season as well as vulnerable children up to age 2.

Vaccines for RSV

After years of research — and many setbacks — some RSV vaccines have crossed the finish line.

The FDA approved three RSV vaccines for adults 60 and older: Mresvia, Arexvy, and Abrysvo. Arexvy can also be given to individuals between the ages of 50 and 59 who are at high risk of developing the illness.

The FDA also approved Abrysvo as a maternal vaccine that can protect infants from RSV before they are even born. It is administered to pregnant women, who develop and pass along antibodies to their babies in the uterus. Infants are highly protected against severe RSV-related disease from birth to age 6 months.

Vaccinating mothers, who can pass the antibodies on to their babies, is a strategy already used with flu and pertussis (whooping cough), McCulloch notes.

• The mother was not vaccinated against RSV while pregnant
• The status of the mother’s RSV vaccination is uncertain
• The child was born within 14 days of the mother’s RSV vaccination

• American Indian/Alaska Native children
• Children with chronic lung disease of prematurity who need medical support during the six months prior to the start of their second RSV season
• Children with severe immunocompromise
• Children with severe cystic fibrosis

However, you should speak with your healthcare provider about what is best for you and/or your child.

Most healthy adults and children handle RSV well, but complications can occur if the virus spreads to the lower respiratory tract.

For both children and adults, RSV can also make chronic health problems worse. For example, those with asthma may experience asthma attacks as a result of RSV infection, notes McCulloch.

Adults with congestive heart failure or chronic obstructive pulmonary disease may experience more severe symptoms or exacerbations triggered by RSV, she adds.

While some research suggests that having severe RSV as a baby can increase a child’s risk of developing asthma, it’s not clear if the connection is one of cause and effect. “We don’t know if kids get asthma because they had severe RSV or if it’s because this child, who was going to have asthma, was more at risk of having RSV because of lung disease,” Michaels explains.

For individuals 65 and over, RSV typically causes anywhere from 60,000 to 160,000 hospitalizations and from 6,000 to 10,000 deaths each year.