What is his preexisting condition. There is nothing here about a compromised immune system. I think he proably had ASTHMA like half the kids in this country.
That’s what I’ve imagined when they state the kids have pre-existing conditions. When my son was young he had asthma, and every cold or virus was a “crisis.”
As to healthy immune system, this type of flu is thought to cause a cytokine storm, which can be more deadly in those with strong immune response than in those with a weakened immune response.
My nephew had a confirmed case of H1N1, but it was rather mild. He was put on Tamiflu and was back in school in a few days.