RSV Vaccines Effective for Seniors With Small Increased Guillain-Barré Risk
A study evaluating the safety and effectiveness of respiratory syncytial virus (RSV) vaccines among older adults has confirmed strong protection against RSV-associated illness. However, it also flagged a small but significant risk of Guillain-Barré syndrome (GBS) following vaccination.
The study, leveraging data from more than 270 million patients across the US, assessed records of 787 822 adults aged 60 years and older tested for RSV during the 2023-2024 RSV season. Vaccine effectiveness (VE) was estimated using a test-negative case-control design, while adverse events were evaluated using a self-controlled case series approach.
Overall, the RSV vaccines demonstrated approximately 75% effectiveness in preventing RSV-associated acute respiratory infection (ARI), emergency department or urgent care visits, and hospitalizations. Effectiveness remained consistent across age groups, including those aged 75 years and older. Importantly, while vaccine effectiveness was slightly reduced in immunocompromised individuals, it remained substantial, ranging from 67% to 73%. However, in patients who had undergone stem cell transplantation, VE dropped considerably, offering only 29.4% to 44.4% protection, depending on age.
The safety analysis, which encompassed more than 4.6 million vaccinated individuals, showed no increased risk for immune thrombocytopenic purpura following vaccination. However, the study identified an elevated risk of GBS, particularly associated with the RSVPreF vaccine, which was linked to 11.2 additional cases per 1 million doses administered. In contrast, the RSVPreF3 + AS01 formulation was associated with a lower excess risk of 5.2 cases per 1 million doses.
While the observed GBS risk was small, the authors emphasized that it is statistically significant and should be considered in clinical decision-making. Given RSV’s substantial disease burden in older populations, the study supports continued vaccination efforts while underscoring the importance of vigilant safety monitoring and patient education regarding potential risks.
Reference
Fry SE, Terebuh P, Kaelber DC, Xu R, Davis PB. Effectiveness and safety of respiratory syncytial virus vaccine for US adults aged 60 years or older. JAMA Netw Open. 2025;8(5):e258322. doi:10.1001/jamanetworkopen.2025.8322
