A version of this story appeared in the February 4 edition of CNN’s Coronavirus: Fact vs. Fiction newsletter. Sign up here to receive the need-to-know headlines every weekday.

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The Covid-19 vaccine developed by the University of Oxford and AstraZeneca not only prevents people from developing symptomatic coronavirus infections, but also appears to slow down transmission of the coronavirus, researchers reported on Tuesday.

The 13-month trial is the first of its kind in the world and could make a significant difference if vaccine shortages continue in the long term, enabling countries to mix and match Covid-19 shots and achieve high levels of immunity in their populations more efficiently.

The trial also seeks to determine whether vaccination is more effective with a four-week or 12-week gap between the two doses. More than 800 people are expected to take part and will begin receiving their first shots by mid-February.

“If we do show that these vaccines can be used interchangeably in the same schedule this will greatly increase the flexibility of vaccine delivery, and could provide clues as to how to increase the breadth of protection against new virus strains,” said Oxford University’s Matthew Snape, chief investigator of the National Immunisation Schedule Evaluation Consortium, leading the trial.

The UK has been one of the world’s worst-hit nations during the pandemic, with among the highest confirmed Covid-19 deaths proportionate to its population. It has, however, launched a successful vaccination program, becoming the first country to approve and administer a fully vetted and clinically tested vaccine. More than 10 million people in the country, around 15% of the population, have received at least one dose to date.

YOU ASKED. WE ANSWERED.

Q: Why do some people still test positive for Covid-19 after a vaccine?

A: It’s too early to tell, the US Food and Drug Administration and regulatory bodies in several other countries say. Vaccines like those made by Pfizer-BioNTech, Moderna and AstraZeneca have been developed rapidly, compared to most other vaccines, which take years to develop.

The FDA said emergency authorization for the Pfizer-BioNTech vaccine was quick, but did not come at the cost of safety. But since Covid-19 vaccines are so new, it’s unclear how long the immunity they bring will last, or whether future booster shots targeting new variants may be required.

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WHAT’S IMPORTANT TODAY

Praising the “good data,” German Chancellor Angela Merkel told German public broadcaster ARD on Tuesday that “every vaccine is welcome in the European Union.”

Confidence in Covid-19 vaccines is rising, according to a new survey that shows 54% of respondents across 15 countries would get a Covid-19 shot if one was offered to them.

The survey, done by the Institute of Global Health Innovation at Imperial College in London, showed that willingness to get vaccinated has increased in 11 of the 15 countries since November, when 41% of respondents said they would get vaccinated.

“It is very encouraging to see that, as a number of safe and effective coronavirus vaccines are being rolled out across the world, there has been an apparent positive shift in people’s perceptions of these products,” said Dr. David Nabarro, co-director of the institute.

COVAX promises delivery of more than 337 million doses by June

The organizers of COVAX, a scheme set up to ensure better access to vaccines in low and middle-income countries, say they will distribute more than 337 million doses between the end of February and June.

The doses will cover 3.3% of the total population of the 145 participant countries, including North Korea, which is scheduled to receive 2 million shots. The deliveries will depend on whether manufacturers can make good on their agreed supplies as the world faces a shortage in shots, but the update offers a boost in confidence for some countries awaiting their first shipment of vaccines.

The vast majority of vaccines will be supplied by AstraZeneca, while 1.2 million doses will be from Pfizer, which will be given to countries that meet its rigid cold storage requirements.

Covid destroyed lives. Those left behind bid farewell on Zoom

Trish Skinner and her husband sit on a couch, flip open their iPad cover, and open Zoom. Skinner is attending her father’s funeral 100 miles away in southern England. Dozens of relatives will join her on this call.

The Zoom call is as much closure as Skinner, 72, will get for the death of her father, Herbert John Tate, who lived to 103. “It’s not how it’s supposed to be,” she says. “There’s no interaction, physically. And that’s the biggest thing that’s missing during this terrible time.”

As well as taking the lives of loved ones, Covid-19 has robbed millions more of the chance to properly grieve, Mick Krever and Phil Black write, with funerals banned or limited to small numbers of socially distanced mourners to reduce the risk of coronavirus spreading.

Australian Open players back in quarantine after positive Covid-19 case

Covid-19 testing at the Australia Open in Melbourne has begun for more than 500 people in quarantine – including 160 players – who went into isolation on Wednesday after a hotel quarantine worker tested positive for the virus.

The single positive case prompted a tightening of restrictions across the state of Victoria, where people now must wear masks in all public indoor spaces and the number of guests allowed in private homes was cut from 30 to 15. The case emerged soon after Premier Daniel Andrews announced the state had “technically” eliminated the virus, after 28 days of no new infections.

Tennis Australia CEO Craig Tiley said players were “casual contacts” and that there was a “very low probability that any will test positive.” All play at the Melbourne Park tennis center was suspended Thursday to allow for testing.

ON OUR RADAR

A health worker fills a syringe with the Moderna Covid-19 vaccine in Boston, Massachusetts, on December 24, 2020.

TOP TIP

Wondering when you can stop wearing a mask, eat inside a restaurant, travel, go to sporting events and concerts, or freely visit friends and family? CNN spoke to experts to find out.

TODAY’S PODCAST

“We will enter the post-pandemic period. I think that period might be a little bit like the Roaring ’20s of the 20th century, after the 1918 Spanish influenza pandemic, but now a kind of Roaring ‘20s of the 21st century.” — Dr. Nicholas Christakis, physician and sociologist

In this episode, Christakis shares his opinion on what will follow the pandemic, and sees a bright light at the end of the tunnel. Listen now.