The U.S. Centers for Disease Control and Prevention (CDC) this week said that reports of a nervous system disorder known as Guillain-Barre syndrome are “more common than expected” in older adults who got new RSV vaccines.
More than 10 million older adults have gotten either Pfizer or GSK single-dose shots since early August to protect against respiratory syncytial virus, or RSV, which is a common cause of cold-like symptoms and can be dangerous for infants and older people.
“RSV vaccination continues to be recommended for adults aged [60 years and older] using shared clinical decision-making. CDC and FDA are conducting active safety evaluations to assess risks for GBS and other adverse events of special interest after RSV vaccination. The results of these studies will help guide future CDC RSV vaccine recommendations,” the CDC said Thursday.
Both the CDC and the U.S. Food and Drug Administration say they’re evaluating any risks, but they do not plan to change their recommendation for the RSV vaccines, which is that patients 60 and older should talk to their doctor and then decide whether to be vaccinated.
The new CDC report focused on 28 cases of the syndrome in people who were vaccinated, and all but one developed symptoms within 21 days. That translated to 1.5 cases per million in people who got the GSK RSV vaccine, and five cases per million in recipients of the Pfizer shot.
In February, the CDC presented similar findings on the RSV shots and Guillain-Barre syndrome.
Around 3,000 to 6,000 people develop GBS in the United States each year—either after being infected by a virus or linked to a vaccination—and it’s more common in older people, according to the CDC. Most people fully recover, but some have permanent nerve damage.
About two cases of GBS have been reported among 1 million people within three weeks of getting an RSV vaccine.
In May 2023, the FDA granted authorization to use two different vaccines, including Pfizer’s Abrysvo shot, for RSV, with officials recommending a single shot for adults aged 60 and older. The CDC also recommended that pregnant women receive the shot, which they said would prevent the infection among babies.
What Is Guillain-Barre Syndrome and RSV?
RSV is a very common virus that can cause infections in the respiratory tract and lungs, often occurring in children before the age of 2, according to the Mayo Clinic’s website.Symptoms include a low-grade fever, dry cough, runny nose, headache, or sore throat, although severe cases can include rapid breathing or wheezing, a severe cough, a fever, or a bluish skin color due to a lack of oxygen.
Symptoms can include a loss of sensation in the legs or arms, problems breathing, or muscle weakness, officials say. The condition generally lasts only a few weeks, and most people with GBS make a recovery without long-term issues.
But GBS can be fatal. According to the website, a small number of patients “die from complications, which can include paralysis of the muscles that control breathing, blood infection, lung clots, or cardiac arrest.”
“In rare instances, vaccinations may increase the risk of people getting GBS, but the chance of this occurring is extremely low,” WHO says. “Studies show that people are much more likely to get GBS from infections such as the flu than from the vaccine given to prevent the infection, in this case the flu vaccine. Occasionally, surgery can trigger GBS.”
