Excerpts from
this WSJ article (paywall). Emphasis mine.
Teenage girls across the globe have been showing up at doctors’ offices with tics—physical jerking movements and verbal outbursts—since the start of the pandemic.
Movement-disorder doctors were stumped at first. Girls with tics are rare, and these teens had an unusually high number of them, which had developed suddenly. After months of studying the patients and consulting with one another, experts at top pediatric hospitals in the U.S., Canada, Australia and the U.K. discovered that most of the girls had something in common: TikTok.
According to a spate of recent medical journal articles, doctors say the girls had been watching videos of TikTok influencers who said they had Tourette syndrome, a nervous-system disorder that causes people to make repetitive, involuntary movements or sounds.
...
Specialists at other major institutions have also reported similar surges. Since March 2020, Texas Children’s Hospital has reported seeing approximately 60 teens with such tics, whereas doctors there saw one or two cases a year before the pandemic. At the Johns Hopkins University Tourette’s Center, 10% to 20% of pediatric patients have described acute-onset tic-like behaviors, up from 2% to 3% a year before the pandemic, according to Joseph McGuire, an associate professor in the university’s department of psychiatry and behavioral sciences. Between March and June this year, Rush University Medical Center in Chicago said it saw 20 patients with these tics, up from 10 the full year before.
Doctors say most of the teens have previously diagnosed anxiety or depression that was brought on or exacerbated by the pandemic. ...
... Caroline Olvera, a movement-disorders fellow, noticed that numerous teens were saying the word “beans,” often in a British accent. Even patients who didn’t speak English were saying it. Some patients mentioned they had seen TikTok videos of others with tics.
Dr. Olvera created a TikTok account and started watching videos of teens and adults who said they had Tourette syndrome. She discovered that one top Tourette influencer was a Brit who often blurted out the word “beans.”
Dr. Olvera, who studied 3,000 such TikTok videos as part of her research, also found that 19 of the 28 most-followed Tourette influencers on TikTok reported developing new tics as a result of watching other creators’ videos.
Clusters of tic-like disorders have happened previously, including a famous case a decade ago in which several teens in upstate New York developed tics that were diagnosed as “mass psychogenic illness.”
Such cases were mostly confined to specific geographic locations, but social media appears to be providing a new way for psychological disorders to spread quickly around the world, according to a recent paper written by Mariam Hull, a child neurologist at Texas Children’s Hospital who specializes in pediatric movement disorders.