a) the Brazilian study was not giving zinc, other studies did not mention it I think.
b) The more susceptible patients are deficient in many nutrients, they need the zinc to enable the HPQ to function
c) the first signs in some coronavirus patients is the loss of sense of taste and sense of smell. This indicates a zinc deficiency, as all the zinc in the body has been utilized in fighting coronavirus, so it shows zinc is a must to treat it.