I have been using nasal flush "as needed", not all the time. Which means that everytime there is slightest irritation in nasal cavities, I start flushing. So no

I have been using nasal flush "as needed", not all the time. Which means that everytime there is slightest irritation in nasal cavities, I start flushing. So no common cold for 50 years. But in this Covid-era I have been flushing everytime I been exposed to humans in tight spaces. Luckily I have in my neighborhood very unpopular and expensive food market with no other customers.