An April 30 study from the CDC found that reports of syncope, or fainting, after vaccination were approximately 164 times more common following the Johnson & Johnson vaccine than the flu vaccine. Overall, however, fainting is still extremely rare. Researchers found that 17 incidences of fainting after receiving the Johnson & Johnson vaccine occurred across five mass vaccination sites, which translates to 8.2 fainting incidents per 100,000 vaccinated people. On the other hand, the flu vaccine resulted in only 0.05 cases of fainting per 100,000 vaccinated people in the 2019 to 2020 year. The study noted that these reports of fainting were prior to the Johnson & Johnson pause, so the fainting would not have been triggered by anxiety surrounding that decision. Authors of the study told NBC that the reports came in over three days, from April 7 to 9. The cases spanned five different states, including California, Colorado, Georgia, Iowa, and North Carolina. Four out of the five clinics were temporarily shuttered, as officials worked to understand the reactions, NBC reported. And for more vaccine reactions you might not have heard about, discover The Common Vaccine Side Effect That No One Is Talking About, Experts Say. The five mass vaccination sites in the study reported a total of 65 anxiety-related events, including the 17 incidents of fainting, in people who got the Johnson & Johnson vaccine. These events occurred immediately after vaccination, within the 15-minute observation period. The anxiety related-events the study focused on included rapid heart rate, rapid breathing, difficulty breathing, chest pain, numbness or tingling, light-headedness, low blood pressure, headache, pale coloring, and fainting. And for more distinctive side effects, Pfizer Caused This Reaction in Half of Recipients, New Study Says.ae0fcc31ae342fd3a1346ebb1f342fcb The study noted that about one-quarter of the anxiety-related events reported after the Johnson & Johnson vaccine came from people who self-identified as having had a similar experience after other vaccinations. “Because the Janssen COVID-19 vaccine is administered as a single dose, this vaccine might be a more attractive option for persons who have needle aversion,” the study authors suggested. “Therefore, it is possible that some persons seeking Janssen COVID-19 vaccination could be more highly predisposed to anxiety-related events after being vaccinated.” The researchers also noted that “the stress of an ongoing pandemic might also increase anxiety surrounding COVID-19 vaccination.” Furthermore, these anxiety-related events happened at a mass vaccination site, which may compound the anxiety of the situation, the study pointed out. And for more COVID vaccine news delivered straight to your inbox, sign up for our daily newsletter. According to the study, about half of the reports of fainting following the Johnson & Johnson vaccine were from people in the youngest age group, 18 to 29 years old. Researchers said fainting following vaccinations is most common among adolescents generally. They noted that the rate of fainting after the quadrivalent HPV vaccine, which people tend to get in their adolescence, has a rate of 7.8 events of fainting per 100,000 doses. “As use of COVID-19 vaccines expands into younger age groups, providers should be aware that younger persons might be more highly predisposed to anxiety-related events after vaccination than are older persons,” the study noted. And for more on vaccine side effects, Moderna Caused This Reaction in 82 Percent of People, New Study Says.