President Donald Trump began a fourth day of treatment for Covid-19 at a military hospital outside Washington, with the severity of his illness unclear barely four weeks before Americans go to the polls to decide whether to reelect him.

President Donald Trump was treated with an experimental antibody cocktail for Covid-19 and moved to a military hospital as a precautionary measure, White House officials said.

AstraZeneca should still know by year-end whether the company’s experimental vaccine protects people against coronavirus, as long as AZD1222 is cleared to resume trials soon, the drugmaker’s chief executive said amid doubts over the potential vaccine’s rollout.

Thermo Fisher Scientific Inc. expanded the company’s response to the COVID-19 pandemic by developing a total antibodies test in collaboration with WuXi Diagnostics and Mayo Clinic.