Myocarditis is usually caused by a viral or bacterial infection. A different vaccine, one against smallpox, has previously been linked to it. There’s a wide spectrum of myocarditis. Some people don’t feel anything and they’re fine without treatment. For others, it can be deadly.

But generally, when young people developed myocarditis following vaccination, the numbers were small, and the level of sickness was relatively mild.

“Many times, people have myocarditis and don’t even know it. It goes away and they’re fine,” said Dr. Stuart Berger at Northwestern University Feinberg School of Medicine. In most of these post-vaccination cases, patients had a full recovery.

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What the Delta variant could mean for Covid-19 in the US

A coronavirus variant first spotted in India is expected poised to soon become the dominant one in the United States, where infectious disease modelers say it could cause a “resurgence” of Covid-19 later this year. And it may already account for 1 in every 5 infections nationwide, experts say.

Meet Japan’s Olympics superfans who want Tokyo 2020 to go ahead

Kyoko Ishikawa is not your average Olympics enthusiast. Sporting a bandana, fans, whistle and traditional Japanese costume, the IT company president is a superfan who has attended every Summer Games since Barcelona 1992.

She even performs a Japanese cheer routine at each one and hopes to carry on the tradition this year.

“The purpose of my cheer activities is to share the message of love, friendship, and peace,” said Ishikawa. “The Games are the one opportunity where we can share that with people from around the world.”

Organizers are trying to mitigate the risk by setting a 50% cap on spectators at venues, up to a maximum of 10,000 people. They could also restrict the number of fans in the event of a state of emergency or amid any other restrictions to curb the rise of Covid-19 infections.

Pressure mounts on Bolsonaro as Brazil records half a million deaths

On June 18 alone, Brazil accounted for nearly one-third of all Covid-19 deaths worldwide, according to Our World in Data — a figure that experts warn is quickly rising as the virus spreads unchecked throughout the country. The death toll of more than 500,000 is twice as high as it was six months ago, a sign that the mortality rate is accelerating, say experts.

Now pressure on President Jair Bolsonaro and his government is growing: Anti-Bolsonaro rallies were held on Saturday across the country — in Sao Paulo, Rio de Janeiro, Brasilia, Salvador and Recife. The country has suffered from a slow vaccine rollout and staunch resistance to containment measures by Bolsonaro, who has downplayed the gravity of the virus. There is no lockdown and just 11.4% of the population is fully vaccinated.

TOP TIP

If you, or someone you know, is holding off getting the vaccine out of fear it might affect fertility, take heart — there’s nothing to worry about.

Compared to healthy males without Covid-19, the study found a significant increase in inflammation and oxidative stress in sperm cells belonging to men with Covid-19. Their sperm concentration, mobility and shape were also negatively impacted affected by the virus.

The studies add to existing research studies that shows no evidence of a link between female fertility and Covid-19 vaccines — or any vaccine, for that matter.

“There is no clear scientific reason to think the new vaccine would cause fertility problems in adults. Likewise, there’s no scientific reason to believe it would cause fertility problems in teenagers. Those are the facts, regardless of how old the person is.”

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For the first time in more than a year, many of us are ready to imagine the next chapter of our lives. CNN Chief Medical Correspondent Dr. Sanjay Gupta is on a mission to help us approach our new normal mindfully, finding a balance between self-care and productivity, and talking to doctors and researchers about the surprising science behind how we can thrive.