CNET – People can have COVID-19 without knowing it — and that’s a huge threat to public health. “…If you’re an asymptomatic carrier of a disease, it means you have the disease but don’t show any symptoms. In the case of COVID-19, this can be a serious threat because of the way this virus spreads: People who are unaware that they have the virus may not stay home or take precautions, such as wearing a mask or staying six feet apart from others, when they leave their homes. There’s a lot of confusion about what “asymptomatic” really means — part of that comes from a lack of data about asymptomatic COVID-19 carriers, but a large part of that stems from the many different uses of the word “asymptomatic.”  People can contract the novel coronavirus and be truly asymptomatic — meaning the virus infects them and runs its course without ever producing symptoms. Then there are people who are “presymptomatic,” which refers to the time period between infection and appearance of symptoms. With many viruses, people are contagious during presymptomatic phases, and we know this to be true about COVID-19…”