This is believable if you remember that complication rates are a variable independent from a virus's infectiousness. The more aggressively it spreads, the more

This is believable if you remember that complication rates are a variable independent from a virus's infectiousness. The more aggressively it spreads, the more likely at least one person will need hospitalisation, even in a virus with a very low complication rate in general. Or, in other words, there are so many children getting it that the 0.002% complication rate or whatever it was starts showing more.