When it comes to matters of heart health, no amount of exercise is too much, scientists said regarding research that debunks the myth that high levels of vigorous physical activity might not always be beneficial.

Britain became the first country to vaccinate its population with Oxford University and AstraZeneca’s Covid-19 shot on Jan. 4, but Prime Minister Boris Johnson was set to tighten restrictions in England in a bid to slow the spread of cases.

Experts at India’s drugs regulator recommended two coronavirus vaccines for emergency use: one developed by AstraZeneca and Oxford University, and the other backed by a state-run institute.

The Covid-19 vaccine developed by British drugmaker AstraZeneca Plc and Oxford University will likely be authorized for emergency use in the United States in April 2021, the chief adviser for the U.S. Covid-19 vaccine program said.

The United States Department of Defense (DOD) awarded Moderna a contract valued at $1,966,598,000 for an additional 100 million doses of the company’s Covid-19 vaccine.

The European Medicines Authority (EMA) will most likely not be able to approve the Covid-19 vaccine developed by drug maker AstraZeneca and the University of Oxford in January 2021, the watchdog’s Deputy Executive Director Noel Wathion said.

The United Kingdom, which was the first to grant authorization to the vaccine developed by Pfizer and Moderna, is expected to give the green light to the vaccine developed by AstraZeneca and Oxford University this week.

Researchers at the University of Oxford on June 5 quietly made a change to a late-stage clinical trial of their Covid-19 vaccine, an adjustment that might seem minor in a large-scale study, but it masked a mistake that would have potentially far-reaching consequences: Many of the United Kingdom trial subjects had inadvertently been given only about a half dose of the vaccine.

Oxford University’s Covid-19 vaccine candidate has a better immune response when a two full-dose regime is used rather than a full-dose followed by a half-dose booster, the university said, citing data from early trials.

AstraZeneca, which is jointly developing a Covid-19 vaccine with the University of Oxford, plans to begin clinical trials testing the company’s vaccine in combination with Russia’s Sputnik V vaccine by the end of 2020.