Covid accounted for 14 percent of all deaths in the United States from March 2020 until all adults became eligible for the vaccine in April, compared with 11 percent of deaths since then.

Nicholas Christakis is director of the Human Nature Lab at Yale University and author of the bestseller "Apollo’s Arrow." He speaks with Hari Sreenivasan about the next phase of the pandemic based on previous pandemics.

An H.I.V. infection increases the odds of dying from Covid-19 by at least 30 percent, researchers said.

With the adjustment for vaccination, the national death rate is roughly the same as it was two months ago, while the adjusted rates in several states show the pandemic is spreading as fast among the unvaccinated as it did during the winter surge.

A social media post claims that COVID-19 vaccination is unnecessary since unvaccinated people have "escaped every single/>

State public health officials expect that more than half of Colorado's COVID-19 cases are tied to the 'highly contagious' Delta variant.

The once oil-rich country lacks vaccines and performs few tests as Covid-19 rages, with some people choosing to die at home to avoid hospitals short of electricity and oxygen.

Ambulances filled with breathless patients lined up in Brazil as nations around the world set new records Thursday for COVID-19 deaths and new coronavirus infections. The disease surged even in...