What Is RSV?

Respiratory Syncytial Virus Causes RSV Sickness

Cropped image of mother examining baby boy's temperature in bed
Getty Images/Lisa Wikstrand

Respiratory syncytial virus, or RSV, is the virus that causes RSV, with symptoms that resemble a mild cold in most older children and adults. In some babies, however, RSV can cause serious illness.

RSV is very common in children; most have been infected with it by age 2.

People at high risk for serious RSV infection also include the elderly, adults with lung or heart disease, and anyone whose immune system is very weak and less able to fight off infection.

What Are the Symptoms of RSV Infection?

They're very similar to those of a cold and can include:

  • Fever
  • Runny nose
  • Sore throat
  • Mild headache
  • Cough
  • Wheezing

How Is RSV Spread?

RSV is spread through contact and droplet transmission. Anyone who comes into contact with the nasal or oral secretions of someone infected with RSV can become infected -- and transmit it to others as well.

What Is the Treatment?

For most children and adults, RSV infection causes only cold-like symptoms, so the treatment is no different than treating any other cold.

However, in some people, especially babies, RSV can cause difficulty breathing, and treatment may include oxygen therapy, breathing treatment (inhaling medication in mist form using a nebulizer), or mechanical ventilation.

Because RSV treatment is based on symptom severity, anyone with RSV who begins having trouble breathing should seek medical attention immediately.

"How Can I Tell if My Baby Is Having Trouble Breathing?"

Older children and adults who are having breathing problems can say so, but babies can't. Signs of difficulty breathing in babies (especially those less than 6 months old) include:

Nasal flaring. This is wide flaring of the nostrils in and out with each breath. (Think of how an angry bull looks.)

Retracting. The baby's skin around the rib cage pulls in deeply with each breath -- so deeply that each rib visibly stands out, giving a "skeletal" effect.

Excessive Congestion. The infant may seem to be almost constantly choking or gagging on secretions.

Difficulty Feeding. True difficulty sucking -- not just a decrease in the amount the child is eating -- may indicate difficulty breathing. This may also be the case if the infant seems to choke and gag while sucking on a bottle or breastfeeding, or if he or she seems hungry but then gets frustrated and cries when trying to eat.

How Can RSV Be Prevented?

There is no vaccine against RSV, although researchers are hard at work trying to develop one. At this time, the best way to prevent RSV infection is to use good hand hygiene.

Here are some important things you can do to help protect your infant against RSV infection:

  • Make sure anyone who touches your baby washes his or her hands first.
  • Keep your baby away from anyone who is sick, especially with cold symptoms or a fever.
  • Keep your baby away from crowds and large groups.
  • Keep your baby away from tobacco smoke and secondhand smoke.
  • Whenever possible, especially if your baby is at high risk for RSV infection, limit his or her participation in childcare during flu season.
  • Everyone in your household and babies 6 months old and older should get a flu shot every year as soon as they are available.

Other tips for preventing common illnesses, such as covering your mouth when you cough or sneeze, also help minimize others' risk of catching or spreading RSV. Of course, this is most important for those at highest risk.

An Added Precaution to Consider

An injected medication called Synagis is available to help boost the immune system for very premature babies and other infants at high risk for RSV. It's typically given monthly during flu season until the child reaches his or her second birthday. Synagis is not a vaccine, but if your child is at very high risk for RSV infection, your pediatrician may discuss this option with you.

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Article Sources

  • "Respiratory Syncytial Virus." National Center for Infectious Diseases. Respiratory and Enteric Viruses Branch (Jan 21, 2005). Centers for Disease Control and Prevention (Dec 30, 2007).
  • Meissner CH, Long SS. "Revised indications for the use of palivizumab and respiratory syncytial virus immune globulin intravenous for the prevention of respiratory syncytial virus infections." Pediatrics. 2003;112(6):1447.
  • Parenting Corner Q&A: RSV, Feb 2007. "What is RSV and how can I protect my child from getting it?" American Academy of Pediatrics (Dec 30, 2007).
  • “Respiratory syncytial virus.” MayoClinic.Org (2014).