A study out of Houston shows there are thousands of strains of COVID-19. Scientists at Houston Methodist Hospital looked at five thousand, 85 genetic sequences seen in two waves of the virus in ethnically diverse Houston. The first was in March, and a much more massive outbreak hit the city in late June. Baylor College of Medicine vaccine expert Dr. Peter Hotez says this is not a revelation. He says RNA viruses mutate. Hotez does not think the mutations have accumulated to changing plans for a vaccine. He says the modifications are not evolving to the point as to how aggressive the virus is or how sick it can make a person. The data has been useful to identify where the virus came. For example, the virus that hit New York came from Europe.