The number of known COVID-19 cases in the world has topped 500 million, but that number is believed to be a vast undercount. One recent analysis by the World Health Organization estimated that the total number of people in Africa who have been infected may be almost 100 times higher than the official count. Meanwhile, new data from the CDC shows more people died in the United States in 2021 than any previous year, due to a rise in COVID deaths. The agency said about 415,000 people with COVID died in 2021 compared to about 350,000 the previous year. In other pandemic news, COVID cases continue to rise in the Northeast and other parts of the country. In recent days a number of colleges have reinstated some form of indoor mask mandates — the list includes Columbia, American, Georgetown, Johns Hopkins and Rice universities.