A woman and child walk through a field of white flags on the Mall near the Washington Monument in Washington, DC on September 16, 2021. Mandel Ngan | AFP | Getty ImagesCovid-19 is officially the most deadly outbreak in recent American history, surpassing the estimated U.S. fatalities from the 1918 influenza pandemic, according to data compiled by Johns Hopkins University. Reported U.S. deaths due to Covid crossed 675,000 on Monday, and are rising at an average of more than 1,900 fatalities per day, Johns Hopkins data shows. Globally, the 1918 flu killed more people, an estimated 20 million to 50 million, according to the World Health Organization. Covid has taken the lives of approximately 4.7 million people worldwide so far, according to Johns Hopkins data.