Claim about Gavin Newsom’s reaction to a COVID-19 booster shot is conjecture

A tech millionaire is floating an unsubstantiated theory that California’s governor experienced a rare illness after receiving a COVID-19 booster shot.

Steve Kirsch posted an article Nov. 9 on Substack headlined, "Gavin Newsom is out of sight likely because he has Guillain-Barre syndrome from his booster shot." Within hours of publishing it, Kirsch changed the headline to remove the reference to Guillain-Barre and wrote instead that it was likely Bell's palsy.

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

Evidence does not support the claim that Gov. Gavin Newsom has either Guillain-Barre syndrome or Bell's palsy. We did not find any news reports about it by credible outlets, and the information Kirsch provided to support his theory is speculative and cites unnamed sources.

Also, Newsom’s spokesperson told a media outlet that the governor did not have an adverse reaction to the vaccine.

Guillain-Barre is a rare disorder in which the immune system attacks the body’s nerves. The single-shot Johnson & Johnson COVID-19 vaccine was linked to a tiny risk —  about 0.0008% — of being diagnosed with Guillain-Barre, according to the Cleveland Clinic. None of the other COVID-19 vaccines are associated with a risk of the illness.

Newsom received the Johnson & Johnson vaccine in April 2021 and a Moderna booster in October, his office reported.

During the drug trial for the Moderna vaccine, Bell’s palsy, a type of facial paralysis, occurred in four of 30,000 participants. Later analysis showed that Pfizer and Moderna vaccines "did not have a higher reported rate of facial paralysis than other viral vaccines," according to MedPage Today.

Newsom received a COVID-19 vaccine booster shot on Oct. 27. A few days later, he canceled a planned trip to the United Nations climate change summit in Scotland, citing family obligations, and remained largely out of the public eye for more than a week. His lack of public appearances, unusual for him, fueled speculation and misinformation.

During that time, however, Newsom did attend a high-profile wedding on Nov. 6, and his staff also said he was working at the state Capitol. On Nov. 9, he attended the California Economic Summit.

Kirsch’s writing cited a changing list of factors to support his theory about the governor’s health. When he posted his initial version of the article with the headline about Guillain-Barre, it said he was relying on information such as Twitter reports of facial paralysis, a "soft" confirmation from a friend who "absolutely" knows Newsom; and information from Alex Jones, who runs a website known for disseminating fake news and conspiracy theories.

​​Later, when Kirsch changed the article headline to say he believed Newsom has Bell’s palsy, he provided a different list of factors influencing his theory. Those included a homegrown analysis of VAERS data that shows an elevated risk of Bell’s palsy after vaccination; his belief that Bell’s palsy is common after receiving the Moderna vaccine; and confirmation he received from "someone who would absolutely know for sure." He also wrote that his unnamed good friend "knows people who are very close to the Governor who confirmed he was vaccine injured."

Featured Fact-check

Facebook posts

stated on March 30, 2020 in a Facebook post

Says certain states are banning the sale of alcohol.

We contacted Kirsch for comment. In response, he provided two sets of screenshots of Newsom, taken from videos of the governor’s public appearances. One set, which Kirsch called "Newsom before," shows the governor on June 16 as a guest on "The Late Late Show with James Corden." The second set of photos, which Kirsch called "Newsom after," is from the governor’s first public appearance after being out of the public eye, on Nov. 9 at the California Economic Summit.

In his Substack article, Kirsch wrote that he had shown the videos to an unidentified neurologist "who said ‘100%’ (Newsom) is recovering from Bell’s palsy due to lingering ‘telltale’ signs."

Kirsch told PolitiFact in an email, "I don’t think anyone came up with a hypothesis that is a better fit to all the data."

Kirsch founded a group called COVID-19 Early Treatment Fund, which had a promising start testing drugs that are FDA-approved for other diseases as treatments for COVID-19. But in the spring, the group’s entire scientific advisory board resigned, citing Kirsch’s "alarming dangerous claims and erratic behavior," according to reporting by MIT Technology Review.

A Substack article said, "Gavin Newsom is out of sight likely because he has Guillain-Barre syndrome from his booster shot."

The article is based on speculation and conjecture and cites numerous unnamed sources, including doctors, making it impossible to replicate or verify the claim. We did not find any news reports about Newsom’s condition by credible outlets, and Newsom’s spokesperson told a media outlet that the governor did not have an adverse reaction to a COVID-19 booster.

We rate this claim False.