RSV

Helpful resources to keep you, your family and kids safe during RSV season.

What You Need to Know Now About Respiratory Syncytial Virus (RSV) and Children

Earlier this year, the FDA approved a therapeutic to prevent severe cases of respiratory syncytial virus in children. What do you need to know about the new drug and RSV? We asked a pediatric infectious disease expert.


It’s the time of the year when holiday festivities excite us, and winter illnesses like RSV infection may sideline us.

Respiratory syncytial virus (RSV) season typically begins in the fall and peaks during winter. The virus, which features cold-like symptoms, affects people of all ages, though children are particularly prone to it. Babies — especially preterm infants, those with health issues and any infant younger than 6 months old — are at risk for hospitalization with RSV. And even though there is no specific treatment for the virus, earlier this year, the Food and Drug Administration (FDA) approved a new therapeutic in the form of a shot to prevent severe cases of RSV and hospitalization in babies and toddlers. Supply is limited but talk to your pediatrician to see if your infant is eligible for the therapeutic.

In the meantime, we spoke with Rachel Orscheln, MD, a Washington University physician at St. Louis Children’s Hospital who specializes in pediatric infectious disease, regarding everything you need to know about RSV, including when to seek medical care and what the new therapeutic is designed to do.

Orscheln: RSV stands for respiratory syncytial virus. It's one of the respiratory viruses that we see circulating in the wintertime. In the United States, RSV season starts in the fall and peaks in the wintertime, and it spreads through contact with respiratory droplets or respiratory secretions. This can happen if someone coughs or sneezes on you, or, for parents, if you’re dealing with a child who has lots of respiratory secretions. This infection can also transmit if people's respiratory secretions get on objects like doorknobs, and then you touch those and touch your eyes, nose or mouth. The symptoms of RSV typically begin about four to six days after you’re exposed and infected with the virus. To avoid getting RSV, avoid people who are sick, and avoid taking infants into crowded indoor areas during RSV season.

There are no specific signs or symptoms that distinguish RSV from other respiratory viral infections. The symptoms can include: fever, runny nose, coughing, sneezing and wheezing. In younger infants and other people with chronic medical conditions, you can see increased effort to breathe. Sometimes infants present with only irritability, decreased activity or apnea, which is pausing in their breathing.

A PCR or an antigen test via a nasal swab.

Signs in a child that would prompt the need for additional medical care might include rapid breathing, pulling of the muscles and using accessory muscles like the abdominal muscles to breathe. This might be noticeable when a child is unable to take their bottle or nurse because of their breathing. Any bluish discoloration of the lips would prompt the need for immediate care. Any child with difficulty breathing should be seen and evaluated urgently.

St. Louis Children’s Hospital has six pediatric ER locations across the St. Louis and southern Illinois region. For milder cases, Washington University Children’s After Hours locations provide convenient medical care for your child’s illnesses and injuries as a faster alternative to ERs when your pediatrician’s office is closed. For most cases, children can be seen here or in a BJC Medical Group Convenient Care, rather than in the ER.

It’s likely due to many factors, but young children have smaller airways. When inflammation occurs, that impedes their breathing. Also, when experiencing the infection for the first time, as an infant, symptoms tend to be the most severe because you don’t have preexisting immunity.

It’s generally related to increased work to breathe: breathing too rapidly, drop in their oxygen saturation and respiratory pauses. Sometimes that contributes to the inability to drink liquids, either to nurse or to take a bottle, so that leads to concerns of dehydration.

In very young infants, especially those less than 30 days old, any fever is a reason to be evaluated and potentially admitted to the hospital because, in that age group, it's not possible to distinguish a fever due to RSV from a fever caused by a serious bacterial infection.

All parents of infants under 8 months of age during their first RSV season should talk to their pediatrician about it.

If the infant’s birth mother was vaccinated at the recommended gestation of between 32 and 36 weeks, and the birth took place at least two weeks after vaccination, the infant is protected from RSV.

There are also certain kids between the ages of 8 and 19 months with increased risk for severe RSV, due to underlying conditions, who would be eligible for this.

Eligibility guidelines can change depending on supply, so check with your pediatrician if you are uncertain.

It's not going to prevent all infections, but it does reduce the chances that a child will need to see a doctor or be hospitalized for RSV. In clinical trials, this [RSV therapeutic] was 74.5 percent effective in preventing lower respiratory tract infection requiring medical attention and 62.1 percent effective in preventing hospitalization. So, it reduces severe illness and reduces hospitalization but doesn't prevent it altogether.

The side effects in the clinical trials were mostly the kind of things we typically see with immunization: pain, redness or swelling at the injection site. There were no serious allergic reactions, but it is possible that someone could be allergic. It was generally well-tolerated and safe.

For most healthy infants, it’s only given during the first RSV season. For kids who are at risk of more severe disease, they can get a second dose between 8 and 19 months of age during their second RSV season.

If you look in the medical literature, there’s been recognition that severe RSV in childhood is associated with long-term complications, including impaired lung function, recurrent wheezing and asthma. However, this is just an association as it remains unclear whether RSV caused the complications, or whether, conversely, those conditions were always present and made worse by RSV.

Parents are encouraged to ask their pediatrician if their children are eligible for the new RSV therapeutic. Need help finding a pediatrician? Use our online search feature to find a doctor who is accepting new patients near you.

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