Read more about the positive predictive value of a coronavirus test here. This graphic shows what schools across the country need to keep in mind when weighing the risks of reopening their ...

The map below shows which states have seen the highest detections in wastewater: Is COVID on the rise? Recent spikes in COVID-19 cases have been largely driven by a new class of subvariants ...

Scientists in Australia say they have identified how the body's immune system fights the Covid-19 virus. Their research, published in Nature Medicine journal on Tuesday, shows people are ...