(NEXSTAR) — In the week since pop music superstar Justin Bieber announced he has Ramsay Hunt Syndrome, a condition that occurs when a shingles outbreak affects facial nerves, the diagnosis has been co-opted by anti-vaccine advocates online.

Bieber, 28, said in an Instagram video last Friday that he was unable to move half of his face. The singer said he had to cancel his North American tour while getting treatment.

“It is from this virus that attacks the nerve in my ear and my facial nerves and has caused my face to have paralysis,” said Bieber. “As you can see this eye is not blinking. I can’t smile on this side of my face; this nostril will not move. So there’s full paralysis on this side of my face.”

The condition is somewhat similar to the better-known Bell’s palsy, though Ramsay Hunt’s effects are more severe. In the wake of the announcement, several anti-vaccine personalities and social accounts have misattributed the cause of Bieber’s condition to the COVID-19 vaccine. Some had also attempted to tie vaccinations to a mini-stroke that Bieber’s wife Hailey Bieber suffered in March after a blood clot traveled to her brain.

One of the now-flagged-as-misinformation posts read: “Hailey Bieber had a blood clot in her brain. Justin Bieber now has Ramsey Hunt Syndrome. Both issues have been linked to [needle emoji]. The media thinks we are stupid but everyone knows.”

In addition to it being unknown whether or not the Biebers are vaccinated, a roster of medical experts have weighed in to debunk the fake social media rumors.

The Poynter Institute’s Politifact fact-checker discussed one of the reports being used to tout anti-vaccine claims online with one of its co-authors, University of Hong Kong professor Bernard Man Yung Cheung.

Some online have pointed to Cheung’s report as evidence of a link between Ramsay Hunt and COVID-19 vaccines, Poynter explains. But both Cheung and another co-author, Oscar Hou In Chou, say the report — which mentioned one 37 year-old man who developed RHS days after vaccination — doesn’t prove one caused the other. Rather, the report, published in January in the Postgraduate Medical Journal, elaborates that researchers considered that the vaccine could have triggered the syndrome based on timing.

No conclusive evidence is given in the report and both Cheung and Hou propose the vaccine could simply have lowered the man’s immunity to types of herpes viruses already present, causing re-activation of the dormant virus and triggering facial paralysis.

Both researchers say they firmly believe in vaccines.

Cheung told Poynter all vaccines come with risks of side effects, “some of which are frequent but harmless, and some of which are rare but harmful.”

Meanwhile, epidemiologist Dr. Katrine Wallace, of the University of Illinois at Chicago’s School of Public Health, took to TikTok to topple the unproven vaccination claims. Instead, @epidemiologistkat, as she’s known on the video site, says Bieber’s RHS actually serves as a reminder of why you should get vaccinated.

“I’m here to tell you that this problem is a perfect example of why vaccines are important. Ramsay Hunt Syndrome is basically the varicella virus that causes the chickenpox. It can lay dormant in your nervous system for decades and then remerge as shingles. And that is what happened to Justin Bieber. He’s got shingles in his ear and the nerves in his face that control the movement of his eye and his mouth. Vaccinating children for chickenpox will protect against shingles in children and later in their lives as adults… Go get your children vaccinated for chickenpox.”

Dr. Katrine Wallace

Wallace also reiterates that vaccines don’t cause shingles, either. It’s a fact supported by Dr. Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security.

“Shingles has rarely been reported post-vaccination, but has been reported post-COVID, post-influenza, post-rabies, post-hepatitis A and post-Japanese encephalitis vaccination,” Adalja told Poynter.

Is it fake news?

Cornell University Library has an entire section with resources on how to identify fake news, propaganda and misinformation.

Tips are:

  • Does the statement or post include a link (or links) to credible sources for its claim? Do other credible news outlets you recognize by name report the same thing?
  • Look for Unusual URLs. If they end in I-o or .com/co, it’s likely they aren’t legitimate.
  • Dissect the Layout. Look for grammatical errors, incorrect dates, bold claims with no sources and sensationalist images. These are red flags.
  • Dig Deeper. Who wrote the article? Who hosts/supports the website?
  • Cross Check. Use fact-checking sites to confirm information.
  • Try a reverse image search. If the same photo shows up in unrelated stories, be suspicious.

Additionally, it’s important to assess your own biases and the biases of the people sharing information you see. And as always, it’s important to fact-check before sharing anything.