RSV in Babies and Young Children: Risks, Symptoms and Protection

Key points

• Respiratory syncytial virus (RSV) can be dangerous for babies and some young children.
• Before RSV immunizations, it was the leading cause of infant hospitalization in the U.S. — an estimated 58,000–80,000 children under 5 were hospitalized with it each year.
• Immunization can keep babies from getting very sick.
• Most children get RSV by age 2.

Who is most at risk of severe illness

• Infants and young children — the younger, the higher the risk
• American Indian and Alaska Native children
• Babies born prematurely
• Children with chronic lung disease or congenital heart disease
• Children with weakened immune systems
• Children with severe cystic fibrosis
• Children with neuromuscular disorders, especially those who have trouble swallowing or clearing mucus

Symptoms

RSV may start mildly and get worse a few days in. Early signs:

• runny nose
• eating or drinking less
• cough, which can progress to wheezing or trouble breathing

In babies under 6 months

Infants with RSV almost always have symptoms (adults sometimes have none). In very young babies, look for:

• irritability
• less activity
• eating or drinking less
• apnea — pauses in breathing of more than 10 seconds

Many babies with RSV have no fever.

Severe illness

Usually RSV is a mild, cold-like illness, but it can cause:

• bronchiolitis — inflammation of the small airways in the lungs
• pneumonia — infection of the lungs

Each year, two to three of every 100 babies under 3 months are hospitalized with RSV. In the hospital they may need oxygen, IV fluids if they are not eating and drinking, or mechanical ventilation. Most get better with this supportive care and go home in a few days.

When to get help

Seek medical care if your child has trouble breathing, is not drinking enough, or is getting worse.

Protecting your baby

CDC recommends one of two options:

1. An RSV vaccine for the mother during pregnancy, or
2. An RSV antibody for the baby (and some older babies).

Most babies do not need both. See CDC's guide to immunizations to protect infants.

Sources

Based on "RSV in Infants and Young Children," Centers for Disease Control and Prevention; a work of the United States government in the public domain.