Preventing RSV in Babies: A Scientific Milestone — August 2023 News Brief

Respiratory syncytial virus (RSV) is a common infection in babies and young children. Virtually all children will be infected with RSV by their second birthday. Most infections are mild, causing congestion and cough, but some can be severe, leading to hospitalizations and even death. The children most susceptible to severe disease include premature infants; babies up to 12 month of age; children with conditions like cystic fibrosis, chronic lung disease due to prematurity, or weakened immune systems; and those of Alaskan Native or American Indian races.

Historically, it has been difficult to protect babies and young children from RSV, but in 2023, the Centers for Disease Control and Prevention (CDC) recommended the use of a monoclonal antibody preparation, called nirsevimab (Beyfortus™), to protect the most susceptible infants against RSV. In this video, Dr. Paul Offit, Director of the Vaccine Education Center, discusses this new product as well as its effectiveness in clinical trials, who should receive it and when.


Preventing RSV in babies: A scientific milestone

Paul Offit, MD: Hi, my name is Paul Offit. I'm talking to you today from the Vaccine Education Center at the Children's Hospital of Philadelphia. It's August 17th, 2023. Well, a couple of weeks ago, on August the 3rd of 2023, the Centers for Disease Control and Prevention, or CDC, made an announcement. They had decided to approve a drug called nirsevimab; the trade name is Beyfortus. It's a monoclonal antibody directed against a virus called respiratory syncytial virus, or RSV. And this monoclonal antibody has now been added to the routine vaccine schedule even though, technically, it's not a vaccine, it's a monoclonal antibody directed against the virus.

So, what is RSV? Respiratory syncytial virus is a virus that can infect the lining of the nose and throat, causing congestion and cough. It can infect the windpipe, causing croup. It can infect the small breathing tubes, causing something called bronchiolitis, which causes asthma. And it can infect the lungs, causing pneumonia. It is a common respiratory infection of children. Every year in this country, there are 1.5 million outpatient visits caused by this virus. There's about 500,000 emergency department visits. There's between 60,000 and 80,000 hospitalizations, and most of those hospitalizations, 80% of those hospitalizations, are in otherwise healthy children. And there's about 100 to 300 deaths.

Now, nirsevimab has been tested in studies and found to be about 80% effective at preventing hospitalization and about 90% effective at preventing intensive care unit visits. Plus, it's long-acting, it works for at least five months and probably longer, and is recommended to be given prior to the RSV season, which usually starts around October, peaks around December and January, and then fades around March.

So, the CDC made two recommendations. The first recommendation for the first RSV season was for any child less than 8 months of age, any child, should get this product, and they can get it at the same time as a vaccine, right before the RSV season.

For the second season, for children 8 to 19 months of age, the CDC recommended this vaccine only for certain high-risk groups, not for all children. So, they recommended it for children who had cystic fibrosis, children who had chronic lung disease due to prematurity, children who are immune compromised, or children who are either Alaskan Native or American Indian.

This is an important product. I think it will dramatically lessen probably the most common reason children are hospitalized during the winter.

Thank you.

Related Centers and Programs: Vaccine Education Center