Six years ago, on March 11, 2020, the World Health Organization declared COVID-19 a global pandemic. Here's what else happened on that day.

Covid-19 was never just another cold. We knew it was going to stick around and keep changing to try to get the upper hand on our immune systems. But we’ve changed, too. Our B cells and T cells, ...

COVID-19 viral activity was high in the United States during the first week of September, according to fresh data from the Centers for Disease Control and Prevention. Some regions of the United States ...

The coronavirus pandemic has provided us many quick lessons in biology, epidemiology and most the basic math behind why working from home and moving classes online helps limit the spread. It has also ...

Deaths from COVID-19 have slowed significantly but continue adding to a tally of more than 7 million deaths from the virus in the nearly five years since the World Health Organization (WHO) declared a ...

Get inspired by a weekly roundup on living well, made simple. Sign up for CNN’s Life, But Better newsletter for information and tools designed to improve your well-being. A new coronavirus variant is ...

If the COVID-19 pandemic has done one thing, it’s made us all more familiar with some of the important players in the immune system. Antibodies, B cells, and T cells are among the best known parts of ...

With fall, and by extension, respiratory illness season, underway, COVID-19 cases have continued to fluctuate nationwide. Some regions of the United States are experiencing "very high" and "high" ...

Getting an updated coronavirus vaccine can be particularly challenging this year. The Food and Drug Administration approved those shots for people who are 65 and older or have underlying conditions ...