Respiratory syncytial virus can cause a viral respiratory infection that affects the lungs and respiratory tract in both adults and children.
The illness caused by this virus, pronounced “sin-SISH-ul,” can be as mild as a common cold, but in severe cases may need hospitalization.
Serious cases are most likely to occur in very young children and those with a compromised immune system or certain chronic diseases.
Respiratory syncytial virus (RSV) is a highly contagious virus that affects the respiratory system.
Most children will have been exposed to RSV by the time they reach 2 years old.
Among adults, it is most likely to affect older adults
The virus is a common cause of various respiratory complaints.
Symptoms can be mild, like those of a cold. However, if it affects the lower respiratory tract, it bronchiolitis and pneumonia can develop.
In 1 to 2 percent of infants below the age of 6 months with RSV will need to spend time in the hospital.
RSV is highly contagious and it spreads through droplet transmission. When a person with the infection coughs or sneezes, secretions from their respiratory tract containing the virus are passed out into the air.
RSV can survive for hours on surfaces such as tabletops, hands and clothing, making it easy for the virus to be transmitted from person to person.
A person is usually contagious for 3 to 8 days, but young children and those with a weakened immune system may still be able to pass it on for up to 4 weeks, even after their symptoms disappear.
Those at highest risk for complications or severe symptoms include:
- infants who were born preterm
- those aged younger than 2 years
- older adults
- adults or children with a weakened immune system
- people with congenital heart or chronic lung diseases
- those with other existing medical conditions, such as asthma
Infection is more likely among those who have a child or sibling in daycare or school.
Early symptoms in children and infants include:
- a runny nose
- reduced appetite
- a cough which may be followed by wheezing
Very young infants may show different symptoms from older children or adults, including:
- irritability
- lack of activity
- reduce appetite
- apnea, or pausing for breath while sleeping
RSV can be dangerous in infants, especially in:
- those born pre-term
- infants under the age of 6 months
- those under 2 years with lung, heart, or neuromuscular problems
- children with a weakened immune system
However, most children experience an RSV before the age of 2 years without having any serious problems.
Symptoms are normally seen 3 to 8 days following exposure to the virus.
Children and infants will usually recover within 1 to 2 weeks, but RSV can continues to spread for longer in those aged under 6 months and people with a weakened immune system.
Symptoms of RSV include:
- runny nose
- coughing
- sneezing
- sore throat
- mild headache
- decreased appetite
- fever
- wheezing, rapid breathing and other breathing difficulties
- irritability and decreased activity in infants
- short, shallow and rapid breathing in infants
- blue color to skin (cyanosis).
Possible complications include:
- pneumonia
- bronchiolitis
- middle ear infection
- asthma
- recurrent RSV infections
Occasional recurrences of RSV after an initial infection are common.
Hospitalization can be required in severe cases. This enables health workers to:
- monitor symptoms, especially breathing problems
- offer advanced forms of treatment and medical support, if needed
Bronchiolitis is a lower respiratory tract infection that can result from RSV. It commonly affects those under 2 years old.
The airways become inflamed and infected. The following symptoms may occur:
- fever
- dry, persistent cough
- feeding problems
- wheezing
Most cases are not serious, but if your child has difficulty breathing or feeding, if they have a high temperature, or if they seem tired or irritable, you should call a doctor.
A doctor will carry out a obtain a medical history and carry out a physical examination. This will include a lung evaluation and possibly oxygenation status, using pulse oximetry.
The doctor does not usually need to distinguish between RSV and other viruses, such as other common cold viruses.
However, if a child is very young, is likely to be hospitalized, or has other health conditions, they may decide to make a specific diagnosis and arrange for additional testing to rule out other infections.
These may include laboratory blood tests, chest X-rays, and possibly laboratory evaluation of nasal secretions.
In mild cases, treatment will aim to relieve symptoms.
Measures to improve comfort may include:
- using a cool mist humidifier
- using bulb suction for mucus
- providing increased fluid intake
- maintaining an upright position
- administering nasal saline drops
- possibly, offering acetaminophen, if there is a fever
In severe cases, hospital treatment may include:
- oxygen supplementation
- the removal of mucus from the respiratory tract
- intubation in cases of respiratory failure or severe apnea
In rare cases, inhaled medications such as nebulized bronchodilators may also used. These medications are of limited benefit in treating RSV infection, including bronchiolitis, and are not routinely used.
These medications may include:
- ribavirin (Virazole), an antiviral
- epinephrine, either inhaled or injected, to help relieve symptoms
RSV infections tend to resolve within 1 to 2 weeks, even in severe cases that have required hospitalization.
The best way to prevent the spread of RSV is to follow good hygiene practices.
Handwashing: Always wash your hands after coming into contact with anyone with cold-like symptoms and before coming into contact with a child. This can also help children learn the importance of handwashing.
Keeping surfaces clean: The risk of spreading RSV can be reduced by cleaning surfaces such as toys, tables, and handles.
Coughs and sneezes: Children can be encouraged to cover the mouth when coughing or sneezing, preferably with a handkerchief, or to sneeze into the elbow, to avoid getting droplets on the hand.
Other tips include:
- discouraging sharing of cups and other utensils
- limiting contact with those who have cold-like symptoms
- avoiding smoking and exposure to second-hand smoke
For infants who are at a higher risk of complications if they contract RSV, monthly RSV antibody injections (palivizumab) may be recommended during the RSV season, which tends to be during the winter months in the U.S.