Respiratory syncytial virus (RSV) causes infections of the lungs and respiratory tract. It's so common that most children have been infected with the virus by age 2. Respiratory syncytial (sin-SISH-ul) virus can also infect adults.
In adults and older, healthy children, RSV symptoms are mild and typically mimic the common cold. Self-care measures are usually all that's needed to relieve any discomfort.
RSV can cause severe infection in some people, including babies 12 months and younger (infants), especially premature infants, older adults, people with heart and lung disease, or anyone with a weak immune system (immunocompromised).
Signs and symptoms of respiratory syncytial virus infection most commonly appear about four to six days after exposure to the virus. In adults and older children, RSV usually causes mild cold-like signs and symptoms. These may include:
RSV infection can spread to the lower respiratory tract, causing pneumonia or bronchiolitis -- inflammation of the small airway passages entering the lungs. Signs and symptoms may include:
Infants are most severely affected by RSV. Signs and symptoms of severe RSV infection in infants include:
Most children and adults recover in one to two weeks, although some might have repeated wheezing. Severe or life-threatening infection requiring a hospital stay may occur in premature infants or in anyone who has chronic heart or lung problems.
Because RSV and coronavirus disease 2019 (COVID-19) are both types of respiratory viruses, some symptoms of RSV and COVID-19 can be similar. In children, COVID-19 often results in mild symptoms such as fever, runny nose and cough. For adults with COVID-19, symptoms may be more severe and may include trouble breathing.
Having RSV may lower immunity and increase the risk of getting COVID-19 -- for kids and adults. And these infections may occur together, which can worsen the severity of COVID-19 illness.
If you have symptoms of a respiratory illness, your doctor may recommend testing for COVID-19.
Seek immediate medical attention if your child -- or anyone at risk of severe RSV infection -- has difficulty breathing, a high fever, or a blue color to the skin, particularly on the lips and in the nail beds.
Respiratory syncytial virus enters the body through the eyes, nose or mouth. It spreads easily through the air on infected respiratory droplets. You or your child can become infected if someone with RSV coughs or sneezes near you. The virus also passes to others through direct contact, such as shaking hands.
The virus can live for hours on hard objects such as countertops, crib rails and toys. Touch your mouth, nose or eyes after touching a contaminated object and you're likely to pick up the virus.
An infected person is most contagious during the first week or so after infection. But in infants and those with weakened immunity, the virus may continue to spread even after symptoms go away, for up to four weeks.
By age 2, most children will have been infected with respiratory syncytial virus, but they can get infected by RSV more than once. Children who attend child care centers or who have siblings who attend school are at a higher risk of exposure and reinfection. RSV season -- when outbreaks tend to occur -- is the fall to the end of spring.
People at increased risk of severe or sometimes life-threatening RSV infections include:
Complications of respiratory syncytial virus include:
No vaccine exists for respiratory syncytial virus. But these lifestyle habits can help prevent the spread of this infection:
The medication palivizumab (Synagis), given in the form of a shot (injection), can help protect certain infants and children 2 years old and younger who are at high risk of serious complications from RSV. High-risk children in this age group include those who:
The first injection is given at the start of the RSV season, with monthly injections given during the season. This medication only helps prevent RSV infection. It does not help treat it once symptoms develop.
Talk with your child's doctor to find out if your child would benefit from this medication and to learn more about it. This medication is not recommended for healthy children or for adults.
Scientists continue working to develop a vaccine to protect against RSV.
Your doctor may suspect respiratory syncytial virus based on the findings of a physical exam and the time of year the symptoms occur. During the exam, the doctor will listen to the lungs with a stethoscope to check for wheezing or other abnormal sounds.
Laboratory and imaging tests aren't usually needed. However, they can help diagnose RSV complications or rule out other conditions that may cause similar symptoms. Tests may include:
Treatment for respiratory syncytial virus generally involves self-care measures to make your child more comfortable (supportive care). But hospital care may be needed if severe symptoms occur.
Your doctor may recommend an over-the-counter medication such as acetaminophen (Tylenol, others) to reduce fever. (Never give aspirin to a child.) Use of nasal saline drops and suctioning may help clear a stuffy nose. Your doctor may prescribe antibiotics if there's a bacterial complication, such as bacterial pneumonia.
Keep your child as comfortable as possible. Offer plenty of fluids and watch for signs of loss of body fluids (dehydration), such as dry mouth, little to no urine output, sunken eyes, and extreme fussiness or sleepiness.
If the RSV infection is severe, a hospital stay may be necessary. Treatments at the hospital may include:
An inhaler (bronchodilator) or steroids are not proved to be helpful in treating RSV infection.
You may not be able to shorten the length of a respiratory syncytial virus infection, but you can try to relieve some signs and symptoms.
If your child has RSV, do your best to comfort or distract him or her -- cuddle, read a book or play a quiet game. Other tips for relieving symptoms are:
Unless severe symptoms result in an emergency room (ER) visit, you're likely to start by seeing your family doctor or your child's doctor. Here's some information to help you get ready for your appointment, and know what to expect from your doctor.
Before your appointment, you may want to make a list of:
Questions to ask your doctor may include:
Don't hesitate to ask any additional questions you may think of during your appointment.
Your doctor is likely to ask you a number of questions, such as:
Your doctor will ask additional questions based on your responses, symptoms and needs. Preparing and anticipating questions will help you make the most of your time with the doctor.
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