Governments warn of heart problems from COVID vaccines, but Twitter calls research 'unsafe'

Governments around the world are warning their citizens that COVID-19 vaccines present heart risks in some populations. But if Twitter users try to look up similar research, they may receive a warning that the information is "unsafe."

Japan's Ministry of Health, Labor and Welfare "raised the alert level for 'side reactions'" to the Pfizer and Moderna two-shot mRNA vaccines on Dec. 3, according to an English translation of a report by the Japanese Kyodo News Service. Just the News couldn't find a native English version.

"Serious" symptoms of myocarditis and pericarditis are being reported among the vaccinated "more frequently in young men than usual," the wire report said. But the ministry still generally recommends vaccination because the benefits outweigh the side effects. Conservative website American Thinker flagged the news.

The heart problem figures are much higher for Moderna than for Pfizer recipients, Japanese broadcaster NHK reported. The Japanese ministry said that as of Nov. 14, for every million males who took the Moderna vaccine, 81.79 ages 10-19 and 48.76 in their 20s developed such symptoms. For Pfizer, those figures are 15.66 and 13.32.