RSV Vaccine Recommended for Older Adults Despite Guillain-Barré Syndrome Concerns

Although Guillain-Barré syndrome rates were higher than expected among older adults following respiratory syncytial virus (RSV) vaccination, the benefits of the RSV vaccine outweigh the potential risks in this population. These study results were published in Morbidity and Mortality Weekly Report.

Between May 2023 and April 2024, the Centers for Disease Control and Prevention (CDC) reviewed patient-reported data captured by the V-safe and Vaccine Adverse Event Reporting System (VAERS) to characterize early post-marketing safety findings in adults aged 60 years and older following RSV vaccination. Patients included in the analysis were those who received a single dose of either the Arexvy^® (GlaxoSmithKline Biologicals) or Abrysvo^® (Pfizer Inc.) vaccine and completed at least 1 daily survey on local and systemic reactions within the 6 weeks after vaccination.

A total of 16,220 V-safe patients (median age, 70 years; women, 59.7%) reported receiving an RSV vaccine (Axrevy, 39.5%; Abrysvo, 23.9%; unknown, 36.6%) during the study period.

Symptoms considered possibly related to RSV vaccination were reported by 6328 (39.0%) patients within the first week following vaccination. Injection site symptoms were reported by 2808 (43.9%) and 787 (20.3%) patients who received the Axrevy and Abrysvo vaccines, respectively. Systemic symptoms were reported by 2344 (36.6%) and 839 (21.6%) patients who received the Axrevy and Abrysvo vaccines, respectively.

The most frequently reported symptoms following RSV vaccination were pain at or near the injection site (31%), fatigue or tiredness (20.5%), and muscle or body aches (17.5%).

Other symptoms reported among the study population included sore throat (0.3%), dizziness (0.2%), and runny nose (0.2%).

During the study period, VAERS received 3200 reports from patients (median age, 72; women, 69.9%) who experienced adverse events (AEs) following vaccination. The majority of AEs were reported by patients who received Axrevy (68.5%), followed by those who received Abrysvo (28.8%) and those for whom the vaccine manufacturer was unknown (2.8%).  (Axrevy, 68.5%; Abrysvo, 28.8%; unknown, 2.8%). The most common AEs included pain in an extremity (13.2%), headache (12.9%), pain (12.8%), injection site pain (12.7%), and fatigue (12.2%).

In total, 281 (8.8%) AEs indicated in VAERS were classified as severe. Clinical impressions of the severe AEs included stroke or transient ischemic attack, Guillain-Barré syndrome, atrial fibrillation, other thromboembolic events, encephalitis or aseptic meningitis, immune thrombocytopenia, sepsis, bacteremia, and shoulder pain.

Among 28 reports of Guillain-Barré syndrome, 11 occurred following receipt of the Axrevy vaccine and 17 occurred following receipt of the Abrysvo vaccine. Two of 18 deaths were attributable to Guillain-Barré syndrome.

Study limitations include reporting bias as VAERS is a passive surveillance system, the inability to determine causal associations between AEs and RSV vaccination, and the inability to estimate the magnitude of risk for severe but rare outcomes due to the lack of a comparator group.

According to the researchers, “CDC and FDA are conducting active safety evaluations to assess risks for GBS [Guillain-Barré syndrome] and other adverse events of special interest after RSV vaccination.”

This article originally appeared on Infectious Disease Advisor