He's one of Germany's superstar football players, a role model who's supported charities that help people struggling during the coronavirus pandemic.

But in recent days, Joshua Kimmich's comments about the safety of Covid-19 vaccinations have threatened to take the shine off his image.

Over the weekend, the Bayern Munich midfielder, 26, confirmed reports he had not yet had a vaccine over concerns about long-term studies.

"I am, of course, aware of my responsibility," Kimmich told broadcaster Sky Sport after a match on Saturday.

"I follow all hygiene measures and get tested every two to three days. Everyone should make the decision for themselves."

Still, Kimmich insisted he was not a "Covid denier or an anti-vaxxer".

"There is a very good chance that I will still get vaccinated," he said. "It's simply that I still have some concerns."

Those concerns have been addressed by prominent German health experts and scientists who have criticised Kimmich for not setting a good example and misunderstanding how vaccines work.

They say decades of research shows that long-term health problems are highly unlikely after receiving a vaccination of any kind. Given this, one leading medical ethicist suggested Kimmich had been the victim of Covid disinformation online.

With coronavirus infections on the rise and jab uptake slowing down, there are fears that Kimmich's comments could encourage vaccine hesitancy in Germany.

'That's not how it works'

Because Covid vaccines are relatively new, scientists have not had time to study them over a long period - but that doesn't mean they're not safe.

Covid jabs have been given to millions of people, as well as being tested robustly in clinical trials.

That's why experts stress the benefits of vaccination against Covid outweigh the risks for the vast majority of people.

While Covid jabs will continue to be monitored for safety by regulators, the chance of them causing serious side effects in the short or long term is considered low.

Carsten Watzl, a professor of immunology at Technical University Dortmund, said the belief that vaccines could have long-term side effects was a common "misunderstanding".

"Say: I let myself get vaccinated, and perhaps next year I will have some grave side-effects. That's not how it works," Mr Watzl told the public broadcaster ARD. "The side-effects of a vaccine always appear directly after the vaccination, within a few weeks."

Health authorities worldwide have come to the same conclusion. For example, the US Centers for Disease Control and Prevention (CDC) says, "serious side effects that could cause a long-term health problem are extremely unlikely following any vaccination".

"Millions of people have received Covid-19 vaccines, and no long-term side effects have been detected," the CDC says.