Thanks for the prompt reply. You have explained a complex matter in a simple manner. Point 1 and 3 , I can understand.
For point 2, I have 2 more questions:
1. I have noticed that when an infected person is contact traced , usually his/her close relative or friend were found out to be positive upon testing but completely healthy and asymptomatic. The persons don’t have any symptoms at all. But since they tested positive, they are also isolated as can spread to others even though asymptomatic. After few days of isolation when tested again, they are negative and cleared of virus. Is it possible that even without symptoms, one can clear the virus? What type of immune system is functioning in that case?
2. It is said that approximately for every human cell there are 10 bacterial cells and for every bacterial cell there are 10 viral cells in our human body. So we are made of more microbial cells than our own cells. I have read that human beings normally harbour certain corona viruses in their body always which coexist with us. Is it true? Is it also possible that the viruses always exists in equilibrium with our body and only proliferate when immune system weakens due to internal circumstances like stress and external circumstances like weather.
You can reply if possible. Otherwise also, I’m fine.