I guess my mother knew enough to cure the illness before needing ICU. None of my siblings and me ever got bad enough to need ICU. A stich is time is worth nine. Most common disease was Malaria & TB & Typhoid when I was growing up. My mom knew how to prevent and cure quickly if got sick. I still remember (after 70 years) swallowing bitter quinine pills.
Any books students in medical school can read, are all available for anyone to read.
My mother even cured me from attack of smallpox which has 30%+ mortality rate. I was vaccinated 2 years prior to getting infected with smallpox. I am guessing the vaccine was helpful in fighting the virus. But no vaccine can “prevent” infection because no vaccine has ever built a virus proof filter in respiratory system.
Your mother sounds like an amazing woman. I have deep respect and admiration for people like her.