Health Officials Investigate Potential Link Between New RSV Vaccines and Rare Nervous System Disorder in Older Adults
In a recent development, health officials are investigating a potential link between two new respiratory syncytial virus (RSV) vaccines and cases of a rare nervous system disorder in older adults in the United States. Although the investigation is still ongoing, the number of reported cases is higher than expected, prompting officials to gather more information to determine if the vaccines are causing the problem.
The inquiry is based on fewer than two dozen cases among more than 9.5 million vaccine recipients, according to health officials. While the available information is limited, experts are concerned about the higher-than-expected numbers and are actively working to establish a possible connection between the vaccines and the rare nervous system disorder. The data was presented at a meeting of an expert panel that provides vaccine policy advice to the Centers for Disease Control and Prevention (CDC).
The disorder under investigation is Guillain-Barre syndrome (GBS), a rare illness in which a person’s immune system damages nerve cells, leading to muscle weakness and paralysis. It is estimated that 3,000 to 6,000 people develop GBS in the U.S. each year, with older individuals being more commonly affected. While most people recover fully from GBS, some may experience permanent nerve damage. Although Guillain-Barre can occur after viral infections, there have been instances where cases have been linked to vaccinations.
RSV, or respiratory syncytial virus, is a common cause of cold-like symptoms but can be particularly dangerous for infants and the elderly. Last year, the CDC approved a recommendation made by the advisory panel for a single dose of RSV vaccine for Americans aged 60 and older. The two options available were Abrysvo, manufactured by Pfizer, and Arexvy, manufactured by GSK. The CDC advised patients to consult with their doctors before deciding whether to receive the vaccine.
During clinical trials conducted before the vaccines were approved for sale, instances of Guillain-Barre had already been identified. Therefore, different systems were put in place to monitor any signs of problems. At the expert panel meeting, CDC officials presented an analysis of the reports received by these monitoring systems. Approximately two-thirds of the reported cases occurred in individuals who received the Pfizer vaccine, called Abrysvo. However, officials are also conducting follow-up tracking in individuals who received the GSK vaccine, Arexvy.
Health officials estimate that about two cases of Guillain-Barre may be seen in every 1 million people who receive a vaccine. The CDC analysis found that the rate of Guillain-Barre cases was lower for the GSK vaccine but higher for the Pfizer vaccine, with 4.6 cases per million reported in recipients of the Pfizer shot. These findings suggest a potential increased risk in RSV vaccine recipients aged 60 and older, which requires further exploration, according to Dr. Tom Shimabukuro, a CDC vaccine safety monitoring official.
Representatives from GSK and Pfizer also made statements during the meeting, acknowledging the complexity of identifying safety signals. Pfizer expressed its commitment to continuously monitor and evaluate the safety of Abrysvo and is conducting four safety studies to investigate the possibility of vaccine-related GBS. The CDC also presented estimates showing that the vaccines have prevented thousands of hospitalizations and hundreds of deaths from RSV. Current data indicates that the benefits of vaccination outweigh the potential risks.
As the investigation continues, health officials are working diligently to gather more information and determine any potential link between the new RSV vaccines and Guillain-Barre syndrome in older adults. While the number of reported cases is still relatively small compared to the total number of vaccine recipients, it is crucial to thoroughly investigate any potential risks associated with vaccination to ensure public safety.