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Japan has never had a Covid vaccine mandate – but warns of ‘rare’ heart inflammation side effect from Moderna vaccine, among young men

“Japan drops all vaccine mandates, places myocarditis warning on label,” reads text on what seems to be a screenshot of a news article, doing the rounds on Facebook in South Africa in January 2022.

The claim is also circulating widely elsewhere.

Myocarditis is when the middle layer of the heart wall becomes inflamed. It’s usually caused by a viral, bacterial or fungal infection, or an autoimmune disease. The symptoms include pain or tightness in the chest and difficulty breathing. It’s treatable with anti-inflammatory drugs or antibiotics.

A vaccine mandate is a requirement imposed by a government, army, university, school, company or other institution for people to be vaccinated against a disease. These mandates have saved lives for centuries. But since Covid vaccines were introduced, mandates requiring vaccination against the disease have become controversial.

Has the Japanese government dropped its mandate for citizens to be vaccinated against Covid? And has it labelled all Covid vaccines with a warning that they may cause myocarditis? We investigated.


Covid vaccination ‘not compulsory or mandatory’

The Covid-19 Vaccine information page on the website of Japan’s Ministry of Health, Labour and Welfare (MHLW) clearly states that Covid vaccination is not mandatory.

Under the heading “Consent to vaccination”, it says: “Although we encourage all citizens to receive the Covid-19 vaccination, it is not compulsory or mandatory.”

It adds: “Vaccination will be given only with the consent of the person to be vaccinated after the information provided. Please get vaccinated of your own decision, understanding both the effectiveness in preventing infectious diseases and the risk of side effects. No vaccination will be given without consent.”

And Japan does not appear anywhere in a December 2021 list, compiled by Reuters, of countries with Covid vaccine mandates.

Japan has never had a Covid vaccine mandate, so the mandate couldn’t have been withdrawn. This part of the claim is incorrect.

‘Cancel and rebook a Pfizer vaccine’

But the Japanese government has warned that myocarditis – and pericarditis, a similar condition – may be “rare side effects” of mRNA Covid vaccines, particularly the Moderna vaccine distributed in Japan by the pharmaceutical company Takeda.

“Although extremely rare, mild cases of myocarditis and pericarditis have been reported after vaccination,” Japan’s MHLW website says.

These side effects mainly appear in young men.

“This is more common after the second vaccination than the first vaccination, and tends to be more common among younger people, especially men in their teens and 20’s,” the ministry says.

“These symptoms have been reported more frequently in those who had received the Takeda/Moderna vaccine than the Pfizer vaccine in male adolescents and young adults. So, if you are a male in your teens or 20’s and have already reserved a Takeda/Moderna vaccine shot, you can still cancel and rebook a Pfizer vaccine.”

The Pfizer vaccine is also an mRNA vaccine.

The claim that Japan has “dropped all vaccine mandates” is false – the country never had them. But Japan’s government has warned that myocarditis and pericarditis, treatable inflammatory heart conditions, may be rare side effects, mainly of the Moderna vaccine, that mostly appear in young men.

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