The number of known deaths from COVID-19 has passed 4 million, according to Johns Hopkins The number of known deaths from COVID-19 has passed 4 million, according to Johns Hopkins University, which is tracking both cases and deaths. In the past 100 years, there have been flu and cholera epidemics, the AIDS epidemic and multiple other diseases around the world. VOA's Carol Pearson says the latest research shows many epidemics either don't have to happen or can be contained.