The Centers for Disease Control and Prevention (CDC) recently alerted the public about an increase in respiratory syncytial virus (RSV) activity in some regions of the Southeastern United States. These patterns indicated the onset of the national RSV season, which typically witnesses heightened RSV activity gradually expanding to the north and west in the subsequent 2–3 months. This viral infection can lead to severe complications in vulnerable populations such as infants, young children, and elderly adults.
As we approach 2023-2024 RSV season, the CDC emphasizes the importance of new RSV prevention measures. Among these is a long-acting monoclonal antibody product, nirsevimab (BeyfortusTM, Sanofi and AstraZeneca). It is important for clinicians to offer this drug, especially to infants under 8 months and children aged 8–19 months at heightened risk of severe RSV complications, as soon as it becomes available in the market. There are also two new vaccines, RSVPreF3 (Arexvy, GSK) and RSVpreF (AbrysvoTM, Pfizer), are now available to protect older individuals from the severe consequences of RSV. As respiratory illnesses surge, healthcare professionals should be cautious, and educate patients on available vaccines and considering testing symptomatic high-risk patients not only for RSV, but also for COVID-19 and influenza.
RSV is an RNA virus, primarily transmitted via respiratory droplets or direct contact with contaminated surfaces. The virus disproportionately impacts infants, young children, and older adults, especially those with underlying health conditions. CDC’s data suggest that RSV leads to 58,000–80,000 hospitalizations and 100–300 fatalities in children under 5 years annually. For adults aged 65 and above, RSV results in 60,000–160,000 hospitalizations and 6,000–10,000 deaths each year. Historically, the RSV season has followed a pattern, commencing in the fall and peaking during the winter. This trend was disrupted during the COVID-19 pandemic, presumably due to implemented public health measures that unintentionally curtailed the spread of RSV. The CDC has noticed an uptick in RSV activity in parts of the Southeastern U.S. Surveillance data from Florida and Georgia indicate increasing rates of RSV infections and related hospitalizations.
In 2023, significant advancements have been made in RSV prevention. One development is the introduction of nirsevimab. This FDA-approved long-acting monoclonal antibody has been designed to shield infants and young children at an elevated risk of severe RSV complications. Clinical trials have validated its safety and efficacy, indicating that a single dose can protect infants throughout an average RSV season, slashing the risk of severe complications by approximately 80%. RSVPreF3 and RSVpreF are also recombinant protein vaccines that have gained FDA approval for use in adults 60 years and above. Both vaccines have shown an efficacy rate of over 80% in averting RSV-related lower respiratory tract infections during the first RSV season post-vaccination. These advancements have also developed alongside supply concerns. The CDC urgently advises clinicians to allocate 100mg doses of nirsevimab, primarily to infants at the highest risk. The demand for thi RSV drug, the the first of its kind for children, has exceeded Sanofi’s predictions. Challenges in reimbursement models have further complicated the issue, affecting accessibility, with each dose priced around $500. As RSV activity rises nationally, there’s growing concern regarding the persistent challenges in accessing the drug.
