Signs and symptoms of respiratory syncytial virus infection typically 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 include:
- Congested or runny nose
- Dry cough
- Low-grade fever
- Sore throat
- Mild headache
In severe cases
Respiratory syncytial virus can lead to a lower respiratory tract illness such as pneumonia or bronchiolitis — an inflammation of the small airway passages entering the lungs. Signs and symptoms may include:
- Severe cough
- Wheezing — a high-pitched noise that's usually heard on breathing out (exhaling)
- Rapid breathing or difficulty breathing, which may make the child prefer to sit up rather than lie down
- Bluish color of the skin due to lack of oxygen (cyanosis)
Infants are most severely affected by RSV. They may markedly draw in their chest muscles and the skin between their ribs, indicating that they're having trouble breathing, and their breathing may be short, shallow and rapid. They may cough. Or they may show few, if any, signs of a respiratory tract infection, but will eat poorly and be unusually lethargic and irritable.
Most children and adults recover from the illness in one to two weeks. But in young babies, infants born prematurely, or infants or adults who have chronic heart or lung problems, the virus may cause a more severe — occasionally life-threatening — infection that requires hospitalization.
When to see a doctor
Most cases of respiratory syncytial virus infection aren't life-threatening.
Seek immediate medical attention if your child — or anyone at risk of severe disease — experiences difficulty breathing, runs a high fever or turns blue, particularly on the lips and in the nail beds.
Respiratory syncytial virus enters your body through your eyes, nose or mouth. It spreads easily when infectious respiratory secretions — such as those from coughing or sneezing — are inhaled or passed to others through direct contact, such as shaking hands.
The virus can also live for hours on objects such as countertops and toys. Touch your mouth, nose or eyes after touching a contaminated object, and you're likely to acquire the virus.
An infected person is most contagious in the first few days after infection, but respiratory syncytial virus may spread for up to a few weeks after the start of infection.
By age 2, most children will have been infected with respiratory syncytial virus. Children who attend child care centers or who have siblings who attend school are at a higher risk of exposure. Susceptibility is also greater during the peak RSV season, which typically begins in the fall and ends in the spring.
People at increased risk of severe — sometimes life-threatening — infections include:
- Infants younger than 6 months of age
- Younger children, especially under 1 year of age, who were born prematurely or who have an underlying condition, such as congenital heart or lung disease
- Children with weakened immune systems, such as those undergoing chemotherapy or transplantation
- Infants in crowded child care settings
- Older adults
- Adults with asthma, congestive heart failure or chronic obstructive pulmonary disease
- People with immunodeficiency, including those with certain transplanted organs, leukemia or HIV/AIDS
Complications of respiratory syncytial virus include:
- Hospitalization. When respiratory syncytial virus infection causes severe illness, hospitalization may be required so that doctors can monitor and treat breathing problems and give intravenous (IV) fluids. Most at risk of hospitalization are babies younger than 6 months old, babies who are born prematurely, and babies with congenital heart or lung disease.
- Pneumonia or bronchiolitis. When the respiratory syncytial virus moves from your upper respiratory tract to your lower respiratory tract, inflammation of the lungs (pneumonia) or the lungs' airways (bronchiolitis) can result. This complication can be quite serious in infants, young children, immunocompromised individuals, or people with chronic heart or lung disease.
- Middle ear infection. When microorganisms infiltrate the space behind the eardrum, a middle ear infection (otitis media) can result. This happens most frequently in infants and young children.
- Asthma. There may be a link between severe respiratory syncytial virus and the chance of developing asthma later in life.
- Recurring infections. Once you've been infected with the virus, it's common to have an occasional recurrence of RSV, usually in the form of a common cold. Although subsequent infections typically aren't as severe as the first, they can be serious in older adults or people with chronic heart or lung disease.
No vaccine exists for respiratory syncytial virus. But common-sense precautions can help prevent the spread of this infection:
- Wash your hands frequently. Do so particularly before touching your baby, and teach your children the importance of hand-washing.
- Avoid exposure. Limit your infant's contact with people who have fevers or colds. This is especially important in premature babies and all infants in the first two months of life.
- Keep things clean. Make sure countertops are clean in the kitchen and bathrooms, especially when someone in your family has a cold. Discard used tissues right away.
- Don't share drinking glasses with others. Use your own glass or disposable cups when you or someone else is sick. Label each person's cup.
- Don't smoke. Infants who are exposed to tobacco smoke have a higher risk of contracting RSV and potentially more-severe symptoms. If you do smoke, never do so inside the house or car.
- Wash toys regularly. Do this especially when your child or a playmate is sick.
The medication palivizumab (Synagis) can help protect children under age 2 who are at high risk of serious complications when they get RSV, such as those born prematurely or with congenital heart or lung disease.
The medicine is given monthly for five months during the peak season. The medication isn't helpful in treating respiratory syncytial virus infection once it has developed.
Scientists are working to find a vaccine against the respiratory syncytial virus not only in infants but also in older adults and high-risk adults.