A Cheap, Safe, Readily Available Way to Keep Children Out of the Hospital

Two new strategies to prevent RSV, the most common cause of pediatric hospitalizations, are now available. But a third strategy, which has always been available, is rarely mentioned.

Respiratory syncytial virus (RSV) infects the nose and throat, causing runny nose and cough; it infects the windpipe and vocal cords, causing croup; it infects the small breathing tubes (otherwise known as bronchiolitis), causing wheezing; and it infects the lungs, causing pneumonia. Every year in the United States, RSV causes 1.5 million out-patient visits, 500,000 emergency department visits, 60,000 to 80,000 hospitalizations, and 100 to 300 deaths. RSV is the single most common reason that children in the United States are hospitalized. Most of those who are hospitalized are less than 6 months old and previously healthy.

To prevent this devastating illness, on August 3, 2023, the CDC recommended a drug called nirsevimab (trade name Beyfortus): a long-acting monoclonal antibody that is 80 percent effective at preventing hospitalizations and 90 percent effective at preventing intensive care unit admissions. Nirsevimab is administered as a single, intramuscular, low-volume injection and can be given at the same time as vaccines. The CDC recommended nirsevimab for all babies less than 8 months of age to be given before the winter RSV season.

Nirsevimab isn’t cheap, costing $495 for babies for a single dose. Although private insurers should cover the cost of this monoclonal antibody—and the Vaccine for Children’s Program should cover the cost for those who are uninsured or underinsured—reimbursement will likely be challenging over the next couple of years. Also, the product is currently in short supply, restricting its use to only those at highest risk.  

Six weeks later, on September 22, 2023, the CDC recommended another product to prevent RSV; a vaccine made by Pfizer to be given to a mother during pregnancy; specifically between 32 and 36 weeks’ gestation. Antibodies induced in the mother would then be actively transported across the placenta, protecting the baby for the first 4 to 6 months of life. Like nirsevimab, the maternal vaccine is 80 percent effective at preventing severe RSV for the first 3 months of life and 70 percent for the first 6 months.

Safety of the maternal vaccine, however, was a concern. Pfizer’s vaccine was tested in a 7,000-person trial before licensure. About 3,500 women received the RSV vaccine and 3,500 received placebo. Thirty-three more cases of prematurity occurred in the vaccine group than the placebo group. While these differences weren’t statistically significant, they were concerning.

There is, however, a third way to prevent RSV that is cheap, safe, readily available, and highly effective: breastfeeding. A recent review of 19 studies from 12 countries involving more than 16,000 infants found that exclusive breastfeeding significantly reduced the incidence of out-patient visits, emergency department visits, hospitalizations, length of hospital stay, and need for intensive care. For this reason, both the World Health Organization (WHO) and UNICEF recommend that breastfeeding begin in the first hour of life and continue exclusively for the first 6 months.

Breastfeeding provides a low-tech, safe, and inexpensive way to prevent RSV. Unfortunately, when it comes to preventing this devastating infection, you almost never hear about it.