What is RSV and Why is it Perilous for Seniors?

Respiratory Syncytial Virus (RSV) is a common respiratory virus that usually causes mild, cold-like symptoms. However, for older adults, RSV can lead to severe illness, including pneumonia and hospitalization. Each year, RSV is estimated to cause 60,000-160,000 hospitalizations and 6,000-10,000 deaths among adults 65 years and older in the United States. This makes it a significant public health concern, comparable to influenza.

Unlike influenza, for which we have a yearly vaccine, a widely effective RSV vaccine has been elusive until now. The virus’s ability to mutate and evade the immune system presented a major challenge to vaccine development. Furthermore, previous vaccine attempts in the 1960s actually led to a more severe form of the disease in some children, halting research for decades.

The Breakthrough: FDA Approval of RSV Vaccines

In May and June 2023, the Food and Drug Administration (FDA) approved two RSV vaccines for adults aged 60 years and older: Arexvy (GSK) and Abrysvo (Pfizer). These vaccines represent different approaches to RSV prevention.Arexvy is a recombinant subunit vaccine containing a stabilized prefusion F protein, while Abrysvo utilizes bivalent mRNA technology – similar to some COVID-19 vaccines – also targeting the prefusion F protein.

Clinical trial data has shown both vaccines to be highly effective. Arexvy demonstrated approximately 82.6% efficacy in preventing RSV-associated lower respiratory tract disease (LRTD) with a medical intervention, and 94.1% efficacy against severe LRTD. Abrysvo showed around 85.7% efficacy against severe LRTD. These results were published in the New England Journal of Medicine and presented at major medical conferences.

Who Should Get the RSV vaccine?

The Centers for Disease Control and Prevention (CDC) recommends that adults aged 60 years and older may receive an RSV vaccine, based on shared clinical decision-making with their healthcare provider. This means the decision should be made collaboratively, considering individual risk factors, potential benefits, and patient preferences. Factors to consider include age, underlying health conditions (like heart or