A version of this story appeared in the March 22 edition of CNN’s Coronavirus: Fact vs. Fiction newsletter. Sign up here to receive the need-to-know headlines every weekday.

CNN  — 

The AstraZeneca vaccine is highly effective in all age and ethnicity groups, prevents all cases of hospitalization and does not trigger blood clots, results from a long-awaited clinical trial in the US, Chile and Peru show, paving the way for the shot to win approval from US regulators.

AstraZeneca said Monday that the trial, which included 32,000 people, found the shot prevented symptomatic Covid-19 in 79% of people, and was 100% effective in preventing severe disease and hospitalization.

It also filled a glaring data gap in the over 65s age group, showing an efficacy of 80% in symptomatic disease prevention, slightly higher than the average of all age groups. Regulators in several European nations, including France and Germany, had initially advised against using the shot in over 65s, citing a lack of data.

“We are preparing to submit these findings to the US Food and Drug Administration and for the rollout of millions of doses across America should the vaccine be granted US Emergency Use Authorization,” said Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D.

But how swiftly AstraZeneca can deliver on its agreement with the US to supply 300 million doses is unclear. The company is still struggling to make good on its deliveries to the European Union, inflaming tensions between the EU and UK, which have been embroiled in a months-long tussle over a limited supply of doses.

European Commission President Ursula von der Leyen told Germany’s Funke Mediengruppe the EU could block a delivery bound for the UK if AstraZeneca did not meet its delivery targets to the EU first. UK Defense Secretary Ben Wallace slammed her comments as “counterproductive.”

YOU ASKED. WE ANSWERED.

Q: If the AstraZeneca shot doesn’t cause blood clots, why have some people died of clotting after the vaccine?

A: The European Medicines Agency (EMA) concluded in an investigation last week that the Oxford-AstraZeneca Covid-19 vaccine is “safe and effective,” finding no evidence that the shot is associated with an increase in the overall risk of thromboembolic events, or blood clots.

The regulator could not definitively rule out a possible link between the vaccine and blood clotting related to a very rare condition called Thrombocytopenia – in which a person has a low blood platelet count – including rare cases of clots in the vessels draining blood from the brain (known as CVST).

The EMA stressed that from around 20 million people in the UK and EEA who had received the vaccine as of March 16, it had reviewed only seven cases of blood clots in multiple blood vessels and 18 cases of CVST, making these “rare cases.” A causal link with the vaccine is not proven, but is possible and deserves further analysis, it said.

Blood clots do occur in the general population and during any mass vaccination program, it is normal for some people to experience health issues, like blood clots, for other reasons. Infection with Covid-19 can also cause blood clots, making it difficult to calculate how common these would be in people who have not had the vaccine.

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WHAT’S IMPORTANT TODAY

People enjoying spring break along Ocean Drive at Miami Beach, Florida, on Friday, before a curfew was announced.

Miami Beach officers shoot pepper balls at spring breakers

Miami Beach Police fired pepper balls into crowds of partiers and arrested at least a dozen people late Saturday as the city took extraordinary measures to crack down on spring breakers who officials say are out of control.

The aggressive enforcement actions came just hours after Miami Beach Mayor Dan Gelber declared a state of emergency and set an 8 p.m. curfew, saying the crowds that have descended on the city recently are “more than we can handle.”

The Brazilian town forced to choose who lives and dies

As supplies run low in Brazilian hospitals, one coastal town says it may be forced to take Covid-19 patients off their ventilators due to shortages in the medicines used for intubation, Rodrigo Pedroso and Marcia Reverdosa write.

Coronavirus cases are surging in Brazil, and the country’s health systems are increasingly overwhelmed. In nearly every state across Brazil, occupancy rates in intensive care units are at or above 80%. Some of them are at or above 90%, and a few have exceeded 100% occupancy, forcing them to turn patients away.

Covid-19 cases soar in India as second wave takes hold

India reported 46,951 new Covid-19 cases Monday, the highest single-day rise in more than four months and the sixth consecutive daily increase in infections, Health Ministry data shows. States are tightening restrictions as a second wave engulfs the world’s second most populous nation, which has reported more than 11 million cases and more than 159,000 deaths.

India imposed a nationwide lockdown a year ago but lifted it after three months. Since then, states have imposed a patchwork of restrictions, many of them relatively relaxed and designed to keep the economy running.

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