you can’t get immunity through sickness and recovery and if you need a ventilator…. good luck with that… we have cpap and o2 condensers but only enough for 2 people . At hospital good luck with that.
Also most hospitals have massive fungal infestations inside iv and respiratory equipment just what you need when sick.
Add to that there is a possibility that you only go into remission and the damages from each infection of your interstitial plural lining is cumulative. .. avoiding is by far best idea.