A baby sucks it's thumb following a temperature check.

Respiratory Syncytial Virus (RSV) is a common but potentially serious virus, especially for infants and young children. Most kids will encounter it by age 2, and while it often mimics a cold, it can cause severe symptoms, particularly in infants under 1 year old, and those born prematurely or with lung or heart conditions.

January is often peak time for RSV in the US, with cases surging from October to March. This seasonal uptick requires extra precautions, as symptoms can escalate from mild cold-like signs to serious breathing difficulties.

“If your child shows signs of RSV, like wheezing, rapid breathing, or a 'caving' chest, it’s important to alert your pediatrician," said Victoria Regan, MD, a pediatrician with Children’s Memorial Hermann Pediatrics.

The New RSV Vaccine for Infants and Young Children

To better protect infants from RSV, the FDA approved a new monoclonal antibody treatment called Nirsevimab. The new immunization reduces severity rather than preventing RSV altogether, offering critical protection for infants during peak season. RSV is a virus, so antibiotics are not effective against it.

The Centers for Disease Control and Prevention (CDC) recommends Nirsevimab for babies under 8 months at the start of RSV season, ideally within the first week for newborns born during that time. For infants up to 24 months with high-risk health conditions, a second dose may be needed in the next RSV season.

This antibody treatment lowers the risk of severe RSV, helping prevent complications like bronchiolitis and pneumonia and the need for hospitalization. It’s a key tool in keeping vulnerable infants safe during their highest-risk years.

Myths vs. Facts About RSV

Myth: RSV is only a winter virus.
Fact: RSV can occur year-round, though it’s most common from November to February.

Myth: Only babies and young children are at risk.
Fact: Though RSV is most dangerous for infants, adults can also experience severe RSV complications, especially those over 65.

Myth: The virus is always mild.
Fact: While RSV often appears as a mild respiratory illness with symptoms like fever, cough and congestion, it can worsen quickly in young children, especially those under 1 year old. The virus tends to reach peak symptoms around days 2 to 5. During this time, it’s essential to monitor hydration, as fluid intake can help thin mucus and make breathing easier.

Myth: Like a cold or flu, RSV becomes non-contagious within a day after the fever breaks, and symptoms last at most a week.
Fact: While RSV symptoms may improve within a week or two, individuals can remain contagious for up to a month after infection. Practicing good hygiene—like regular handwashing and disinfecting surfaces—is crucial.

Myth: RSV is only transmitted through respiratory droplets.
Fact: RSV can live on hard surfaces—such as doorknobs, changing tables and crib rails—for hours, making good hand hygiene essential.

RSV is a serious virus, especially during peak season, but with immunizations and good hygiene, parents have more ways to protect their children from severe outcomes.

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