It boosts your immune system.
Virus dies at that temp, but your body is obv much cooler than outside heat, and sauna isn't a cure if you already have it lol. All kinds of weird info and talk our there now starting with wonky homemade sanitizer recipes.
It's not a direct heat otherwise your lungs would burn out.
Immune system is quite important but majority of the people are like "let's build that immune system!". Too little too late imo. It's something you work on for a while, or always, and not just in a panic attack. Still, even with a good immune system, if you're in a contact with somebody who has corona, chances are huge you're getting it. But if you're young, fit and with a good immune system, chances are quite low (lesser than 1% surely) that you will die. It's just that you're a walking danger to elders 'cause you can literally kill them (since it's around 20% death rate in Italy for those who are 80+).