How can we find out if it's true or not?
I recommend checking the EU news sources. I've heard they are doing a pretty good job with data transparency.
One source of EU data is this doctor. He explains what you will find on the EU data bases.
https://youtu.be/0rO9DDganV4?si=Taq4VitXRoUYugye
I do not recommend the American or Canadian news sources.
Canada has just changed the way data is being collected.
Not much transparency in the USA. Many Americans now expect the USGov to lie.
They say the new vaccine should be taken by everyone over 6 months old.
In most of the EU, the new vax isn't recommended for most young people. According to news this month. That could change.