What is Guillain-Barre syndrome? Rare neurological complication linked to Johnson & Johnson COVID-19 vaccine

As the world continues to face down the COVID-19 pandemic, vaccines have emerged as a beacon of hope. Many countries are looking to restore normalcy into the lives of inoculated individuals, with concepts such vaccine passports, and a lifting of curbs for those who have gotten injected. But there may be some hiterto unforeseen complications.

The US Food and Drug Administration (FDA) on Monday warned Johnson & Johnson of possible rare neurological complications associated with its COVID-19 vaccine. While the vaccine continues to be approved for use in the western nation, the FDA has sought a revision in the vaccine recipient and vaccination provider fact sheets for the jab. The complication is known as Guillain-Barre syndrome. And while the FDA said it had not established the vaccine could cause the syndrome, it noted an increase in reports of the sometimes paralyzing condition.

The FDA said 100 preliminary reports of Guillain-Barre syndrome had been filed with the US government's Vaccine Adverse Reporting System, out of 12.8 million Janssen vaccines given. Meanwhile, Johnson & Johnson on Monday (local time) confirmed that they are in talks with the US Food and Drug Administration (FDA) about an increased risk of a rare neurological complication among people who received its single-dose COVID-19 vaccine.

What is Guillain-Barre syndrome?

According to the US Centers for Disease Control and Prevention, Guillain-Barré syndrome or GBS is an "uncommon sickness of the nervous system in which a person’s own immune system damages the nerve cells, causing muscle weakness, and sometimes, paralysis". It has also been linked to outbreaks of the Zika virus.

According to an update by the World Health Organisation, people of all ages can be affected, but it is more common in adults and in males. "Most people recover fully from even the most severe cases of Guillain-Barré syndrome," the website adds.

The symptoms include weakness of the arms and legs and, in severe cases, it can affect the muscles that control breathing. These symptoms can last a few weeks or several months.

While researchers do not fully understand what causes GBS, it is often preceded by an infection. This could be a bacterial or viral infection. The WHO notes that Guillain-Barré syndrome may also be triggered by vaccine administration or surgery.