I’m not an ‘expert’ in medicine or anything, really. I do know how to click on the worldometer website, click on coronavirus, click on Africa and see that Covid 19 is NOT A PROBLEM IN AFRICA. My, that’s odd! Wild guess on this dumbards part is that most of Africa has been given ivermectin or chloroquine for parasitic disease. But, that’s just me. I’m going to go out and refill my dog’s HeartGuard today to have on hand in case....
The Durvet horse paste might be a better answer if you’re near a TSC. I think Amazon is sold out.
India is using Ivermectin and look at their results.