Late effects of Corona

My brother, 53 years old, medical history, contracted Corona late last year, recovered well without much medical support. A few months later, he suffered from breathing problems. He was diagnosed with pneumonia as a late effect of Corona. After antibiotic therapy, he had to continue inhaling with cortisone spray, but did not feel much improvement. I recommended vitamin D3 (4-5000 IU), omega 3 krill (3 caps) and oregano (3×2 caps). Now the can is empty and he feels much better. He likes to blow the alphorn again, walk uphill for 3 hours ..