Respiratory viruses are common in children under 5, particularly those who attend daycare or are exposed to tobacco smoke. Most cases are mild, but for some children, an ordinary cold or flu can quickly turn into respiratory syncytial virus (RSV). Severe cases may require emergency department treatment or hospitalization.

Here’s how it happens:

  • Cold or flu germs get into the child’s nose, mouth or eyes either through the air or direct contact with germ-laden hands, toys or eating utensils.
  • The germs settle in the upper respiratory tract: nose, eyes, sinuses, mouth and upper throat.
  • When the immune system is working efficiently, the sticky mucus that lines your nasal passages and sinuses traps the germs, while tiny hairs called cilia sweep it out of the airways.
  • If germs take hold and infection sets in, your immune system sends extra blood cells to the nasal passages, leaving them swollen, inflamed and congested. At the same time, the nose produces extra mucus, which can overwhelm the cilia’s ability to clean things out – and leave you with a stuffed-up or runny nose.
  • From the nose, germs can spread and cause infection in ears and sinuses. Germs can also move down into the large and small airways of the lungs. This can trigger asthma or lower respiratory tract infections. 

image of a bay sleeping

What symptoms should you watch for in your child?

Contact your child’s doctor if common cold symptoms are complicated by any of the following:

  • The child is younger than three months
  • The child has ever been diagnosed with asthma or reactive airways disease
  • The child has a fever that is:
    • above 100.4° in babies under 3 months old
    • above 101° in babies 3-6 months
    • above 102° in babies older than 6 months
  • Daytime cough or cold symptoms last for more than 10 days
  • Cold symptoms come back a day or two after they seem to go away
  • The child tugs at an ear and develops an earache

These could be signs that your child has developed RSV.

Call 911 or take your child to the emergency room for any of these symptoms:

  • Wheezing (noisy breathing when exhaling)
  • Signs of trouble breathing: nostrils widening with each breath; rapid breathing; skin above or below the ribs sucking in with each breath; skin, lips or nails turning blue
  • A severe headache behind or around the eyes or the back of the neck; swelling or redness around the eyes
  • Persistent vomiting or signs of dehydration: dry or sticky mouth; few or no tears; thirst; discolored or less urine than usual

Infographic is What is RSV. Contains brief description, who is high risk, and the symptoms in infants and older children or adults.

What is Respiratory Syncytial Virus?

RSV is a common respiratory virus. By the time children are 2 or 3 years old, most have had RSV at least once, with few problems. However, for some, the virus can be life-threatening. The infection sends more babies to the hospital than any other condition. High-risk groups include:

High-risk groups include:

  • Babies less than one year who were born prematurely
  • Infants under 6 months
  • Children with asthma or reactive airways disease
  • People of any age with underlying lung, heart or immune system problems, including cancer and transplant patients

RSV tends to occur and spread in the winter and early spring. It starts as an upper respiratory infection, with familiar cold symptoms. What makes it so dangerous is its ability to quickly spread down from the nose and throat into the lower respiratory tract, where it infects and causes inflammation in the tissues of the lungs (causing pneumonia) and the tiny bronchial air tubes (causing bronchiolitis).

Inflammation is the body’s natural process for fighting infection, but in tiny infant airways or those already inflamed by asthma, it can cause increased airway obstruction and difficulty breathing.

Another danger of RSV is that a serious infection in young children increases the child’s risk of developing asthma in later years. Researchers do not know exactly why this happens. It may be a cause-and-effect reaction, where the RSV infection damages the lung, which leads to asthma; or it may just be an association, where factors that put children at risk for asthma also put them at risk for a more serious RSV infection. RSV and other viruses have also been linked to an increased risk of sensitization to allergens and development of allergies.

RSV is also common among adults, particularly those with weakened immune systems such as people with asthma or COPD, cancer patients, people with immunodeficiency or autoimmune diseases. 

Recognizing RSV Symptoms

Parents and caregivers of children with asthma, premature babies and infants – as well as older adults – need to take extra precautions during the RSV season. It’s important to recognize the warning signs of RSV and seek medical treatment as soon as possible for any of the following symptoms:

  • High fever (or low fever if immunocompromised)
  • Rapid breathing or other signs of difficulty breathing
  • Wheezing
  • Worsening, barking cough
  • Skin, lips or nails turning blue 

No Cure, But Treatment is Available

There is no medical cure for RSV. Healthcare professionals focus instead on treatments that reduce congestion and open the airways so the patient can breathe. These treatments may include over-the-counter fever reducers and pain relievers. Check with your doctor which medication is best for your child. Be sure to check age ranges for dosage instructions.

Other at-home treatments may include:

  • drinking plenty of fluids
  • nasal saline drops to relieve a stuffy nose
  • suctioning mucus for young children unable to blow their nose
  • taking a bath or sponge bath with lukewarm (not cold) water

If symptoms cannot be managed at home, the child needs to be hospitalized. Serious cases require hospital care, intravenous fluids, nebulizer medications and oxygen treatments.

Some patients may get secondary pneumonia as a result of RSV infection; this needs to be treated aggressively with antibiotics.

Some high-risk babies may qualify to receive a preventive medicine called palivizumab, given by injection every month during RSV season. Palivizumab is not a vaccine.

RSV Prevention Tips

An RSV monoclonal antibody treatment for infants and young children is now available. The treatment acts similar to a vaccine. In addition, RSV vaccines are available for adults 50+ years of age or older. Vaccines for other age groups are coming soon.

Certain lifestyle changes can help prevent RSV infection. The virus can live on hard surfaces such as doorknobs and tabletops for days. It can spread quickly through human contact, often before the infected person shows any obvious signs of the disease. To help prevent RSV:

  • Wash hands frequently, especially before eating or before handling babies
  • Wash and disinfect toys, tabletops, doorknobs and other shared surfaces
  • Avoid sharing cups, eating utensils or food
  • Avoid people with obvious cold symptoms
  • Avoid cigarette smoke, which can increase the risk of infection and severity of symptoms
  • Don’t let others handle your baby without washing their hands first


Reviewed by:
Purvi Parikh, MD, FACAAI is an adult and pediatric allergist and immunologist at Allergy and Asthma Associates of Murray Hill in New York City. She is on faculty as Clinical Assistant Professor in both departments of Medicine and Pediatrics at New York University School of Medicine.