RSV Prevention

RSV is a major cause of hospitalization for infants. Every year, multiple infants from Heritage Pediatrics are hospitalized due to this infection. Thankfully, a new product (Beyfortus) was made available that prevents RSV infection in infants. This FAQ is intended to educate your family about this new product and help you decide if it’s a good option for your child.


What is RSV and who gets it?

RSV (respiratory syncytial virus) is a seasonal respiratory virus. It is a common virus — most children (~70%) are infected in the first year of life and almost all children (~97%) are infected by 2 years of age. Thereafter, recurrent infections occur throughout life — these are typically mild due to immunity that the body’s developed from the earlier infections.


Who is at risk for severe RSV infections?

RSV is the leading cause of hospitalization in infants in the United States. Two to three percent of infants have been hospitalized with RSV. The risk of hospitalization is the greatest in the first months of life; risk declines with increasing age. Infants with the following medical conditions are at greatest risk of hospitalization from RSV: prematurity, congenital heart disease, chronic lung disease children, and immunocompromising conditions.


When is RSV season?

The RSV season in Texas generally runs from October through March, with a peak in December or January. The peak of RSV season usually precedes the peak of flu season by 1 to 2 months. This year the RSV season started in early October in Texas. The Texas Health Department releases information about RSV cases throughout the state on their website ( .


What are the symptoms of an RSV infection in infants and young children? What is the treatment?

RSV causes a lower respiratory infection called “bronchiolitis”. Young children with bronchiolitis will typically have mild runny nose and cough at the beginning of the illness, followed by cough and respiratory distress. They will often breathe faster than normal and have retractions; doctors will hear certain sounds with their stethoscope during the exam (wheezing, crackles).

There is no antiviral treatment for RSV bronchiolitis. Infants with RSV are helped by supporting their body while their immune system clears the virus. Frequent nasal suctioning, hydration, and monitoring the child’s breathing are the hallmark of caring for infants with bronchiolitis at home. Hospitalized infants with RSV are often given oxygen and IV hydration. Some hospitalized infants with RSV are given breathing treatments.


What is the new RSV prevention product? Is it effective? Is it safe?

Beyfortus (nirsevimab) is a new product developed after decades of research. It contains preformed antibodies that attach to a protein (the F protein) on the outside of the RSV virus. It is given as a single intramuscular shot. Ideally, it’s given shortly before the start of the RSV season to eligible infants.  It provides immediate and short-term protection (around 5 months). Beyfortus is more effective and provides longer protection than a currently available product (Synagis) that is only given to the most vulnerable of infants.

Information about the safety and effectiveness of Beyfortus is derived from 3 clinical trials where it was given to both term and preterm infants. The studies found that Beyfortus reduced the chance of an RSV infection by 70% and reduced the chance of an RSV-related hospitalization by 78%. The protection was greatest in the first 3 months but lasted up to 5 months. Side effects from Beyfortus were rare and mild. The side effects were similar to other injectable medications – mild rash or injection site pain or swelling.

Beyfortus was approved in Europe in November 2022 and by the US FDA in July 2023. The CDC provided recommendations for its use in August 2023.


How do I know if my child is eligible for Beyfortus?

The AAP and CDC recommend the use of Beyfortus for ALL infants under 8 months of age during RSV season. This recommendation is for both term and preterm infants and it includes children who are healthy and children with medical conditions.

For children 8 months to 19 months of age, only those with the following medical conditions are eligible – chronic lung disease of prematurity, cystic fibrosis, and severely immunocompromised.


What if the infant’s mother received an RSV vaccine during pregnancy?  Does the infant still benefit from Beyfortus?

Infants born to mothers who received the maternal RSV vaccine while pregnant generally are not due for Beyfortus.  However, there are exceptions.   Make sure you notify your pediatrician if your infant falls in this category.


Does Heritage Pediatrics recommend Beyfortus?

The doctors at Heritage Pediatrics recommend the use of Beyfortus for all infants who are eligible. Every year we see patients with both mild and severe RSV infections. Every year we have patients that are hospitalized from this virus. We are confident that the research conducted on Beyfortus demonstrate that it is effective and safe. We expect this medicine will significantly reduce the burden of RSV infections in infants.

We also understand that Beyfortus is a new medicine and that families will have varying degrees of comfort with accepting a new medication. We are here to answer any questions you have regarding this product and hope the above FAQ document will help your family make an informed decision.


If I desire Beyfortus for my eligible infant, how do I obtain it?

Heritage Pediatrics is working to rapidly deploy this product for all eligible patients.   We are working to secure enough supply for this 2023-24 season.   We will send targeted notifications to families of infants who may be eligible.   Currently, the manufacturer is not able to supply our complete need.  Therefore, we are only able to provide Beyfortus at the well child visits.  However, we hope to have enough for on demand requests in the coming weeks.   Look for an email from or follow us on Facebook (embedded on our webpage too) for the most up to date supply information.


Is my child required to receive Beyfortus by the State of Texas or Heritage Pediatrics?

Beyfortus is not a required vaccine for Texas nor Heritage Pediatrics.  It is optional risk reduction.


What is the current state of supply of Beyfortus?

Beyfortus was approved for children 0-18 months.   There is currently adequate supply for all infants who are less than 11 lbs.  However, for those over 11 lbs the supply is extremely limited.  For those over 11 lbs it must be rationed to children under 6 months, and children 6-8 months with a high risk condition (premature birth at <29 weeks’ gestation, chronic lung disease of prematurity, hemodynamically significant congenital heart disease, severe immunocompromise, severe cystic fibrosis (either manifestations of severe lung disease or weight-for-length less than 10th percentile), neuromuscular disease or congenital pulmonary abnormalities that impair the ability to clear secretions).

Children with high risk conditions over 8 month up to 24 months should speak with their doctor to determine if Synagis (palivizumab) is right for them.


If Heritage Pediatrics does not have Beyfortus for my infant, can I obtain it somewhere else in San Antonio/South Texas?

We have checked with the local health departments, other pediatric offices, and the manufacturer.   There is nowhere in South Texas that has a significant supply and we do not know of anywhere to recommend you go to obtain Beyfortus.  Retail pharmacies are not an option.



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  • Suh M, Movva N, Jiang X, et al. Respiratory Syncytial Virus Is the Leading Cause of United States Infant Hospitalizations, 2009-2019: A Study of the National (Nationwide) Inpatient Sample. J Infect Dis 2022 226(Suppl 2):S154-S163.
  • Hall CB, Weinberg GA, Blumkin AK, et al. Respiratory syncytial virus-associated hospitalizations among children less than 24 months of age. Pediatrics 2013 132:e341-348.