I looked at the data to check your assertion. In fact nowhere on Earth has a mortality rate of 20%. What you mean, I think, is that of cases that present to hospitals or other care facilities, the mortality rate is 20%. Yemen has experienced a total of 2,000 deaths since the beginning of the pandemic and has a population of 30,000,000. Do the math and you discover that Yemen's fatality rate from covid-19 is 0.007%. We do not help the situation by making false and highly misleading claims that serve only to further frighten people who seem unable to look at the data and understand what it is really telling us. Your claim, unfortunately, is just another entirely spurious misrepresentation and the conclusions you draw are equally erroneous - even doctors now acknowledge that ventilating patients results in a much higher fatality rate than simply administering oxygen via nasal clips.