A version of this story appeared in the February 8 edition of CNN’s Coronavirus: Fact vs. Fiction newsletter. Sign up here to receive the need-to-know headlines every weekday.

CNN  — 

South Africa has paused its rollout of the Oxford-AstraZeneca coronavirus vaccine after a study showed that it offered “minimal protection” against mild or moderate illness caused by the more contagious virus variant first identified there, known as B.1.351.

The findings, which come a week after the first million doses of the Oxford-AstraZeneca vaccine arrived in South Africa, are a damaging setback for the country’s efforts to curtail the pandemic. More than 46,000 people are known to have died from Covid-19 there, and overall cases, which have topped 1.4 million, are now largely being driven by the new variant.

It’s also a big blow for the Oxford-AstraZeneca vaccine, which has been hailed for its low cost and easy storage as one of the world’s best hopes for defeating the virus. And the study is yet another worrying sign of the risks that new mutations pose to vaccine development and deployment, with herd immunity appearing increasingly less achievable.

The B.1.351 variant has been identified in at least 41 countries, including the United States, according to the World Health Organization (WHO). Other variants first spotted in the United Kingdom and Brazil have been detected in dozens more. And they’re spreading rapidly.

It was not clear from the study, which has not yet been peer reviewed, whether the Oxford-AstraZeneca vaccine protected against severe disease from the B.1.351 variant. The 2,000 clinical trial participants were mostly young healthy adults, unlikely to become severely ill. But based on immune responses detected in their blood samples, scientists said there was “still some hope” that the vaccine could protect against more severe cases.

An AstraZeneca spokesperson said in a statement that the company was working with Oxford University to adapt the vaccine against the B.1.351 variant so “it is ready for autumn delivery should it be needed.” Several other manufacturers have said they are trying to address the issue of variants by developing booster shots.

An expert from a World Health Organization team investigating the origins of Covid-19 on the ground in China has lashed out at US President Joe Biden for posturing against Beijing, and taken a shot at the credibility of US intelligence agencies after the State Department expressed uncertainty over the team’s initial findings.

YOU ASKED. WE ANSWERED.

Q: Are Covid-19 vaccines safe for cancer patients?

A: Viruses change all the time and most of the changes, or mutations, are harmless. But sometimes one of the pieces of the virus will acquire a change that gives it an advantage, and that one will come to dominate in a population. And, sometimes, that change can be harmful to the people it infects. Other times, it makes it easier for the virus to be transmitted.

Dr. Bruce Walker, an infectious diseases specialist, says coronavirus variants aren’t just imported – they can also be home grown. He pointed to the case of a 45-year-old patient in Massachusetts, who developed a mutation of the virus resembling variants first identified in South Africa, the UK and Brazil after being sick for months, as proof.

“Calling these things the African variant, the Brazilian variant, may not be so accurate,” Walker, director of the Ragon Institute of Massachusetts General Hospital, MIT and Harvard, said. “I’m not sure that any mutations that are now being detected aren’t just being generated in different countries but along similar paths.”

Send your questions here. Are you a health care worker fighting Covid-19? Message us on WhatsApp about the challenges you’re facing: +1 347-322-0415.

WHAT’S IMPORTANT TODAY

Fears Super Bowl will bring coronavirus surge

Covid-19 cases and hospitalizations are decreasing across much of the United States, but health experts and officials warned that could change if fans gathered Sunday to watch the Super Bowl with people from outside their households.

“When people get together in private residences in close proximity, that is one of the single most effective ways to spread this disease,” Kentucky Public Health Commissioner Dr. Steven Stack said. “We can’t afford to have the disease spread now, with these mutations and these variants.”

New variants circulating in the US are once again putting the country in the “eye of the hurricane,” according to Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine. Nearly 700 cases of coronavirus variants first spotted in the UK, South Africa and Brazil have been reported in the US so far, according to data updated by the Centers for Disease Control and Prevention. The vast majority of those cases are the B.1.1.7 strain, which was first detected in the UK and has now been spotted in at least 33 states. Experts say the highly contagious variant will likely soon become dominant in the US, and a new study found significant community transmission may already be occurring.

Inside Malawi’s Covid-19 wards, the impact of vaccine nationalism is all too clear

A dramatic second wave of Covid-19 in Malawi, fueled by the new variant first discovered in neighboring South Africa, has inundated much of its health infrastructure, leaving many families to make agonizing choices and exposing the danger of deep inequalities in vaccine distribution.

“I used to do regular rounds at district hospitals. It was a way for us to ensure the quality of care across the country,” says Dr. Tamara Phiri, a specialist treating Covid-19 patients at Queen Elizabeth Central Hospital in Blantyre, the largest hospital in southern Malawi.

But like many of Phiri’s other responsibilities, her district visits ended when Covid-19 struck in earnest in Blantyre and her home hospital’s coronavirus admissions hovered near capacity. According to official government data, the record for confirmed single-day Covid-19 cases was nearly seven times higher at the very peak of this second wave compared to the first. David McKenzie and Brent Swails report.

Heartbreak and anger as China discourages travel for Lunar New Year

Normally at this time of year, hundreds of millions of Chinese people would be packing highways, trains and planes on homebound trips to celebrate the Lunar New Year with family.

But this year, the largest annual human migration on Earth has been put on hold, following the Chinese government’s call to avoid “nonessential” trips during the holiday period to prevent a resurgence of the coronavirus. That is a lot to ask. The Lunar New Year, also known as Spring Festival in China, is the most important holiday in the Chinese calendar – the equivalent of Thanksgiving, Christmas and New Year’s Eve combined.

To discourage people from traveling, China’s National Health Commission has imposed new rules that require people returning to rural areas to produce a negative Covid-19 test taken within the previous seven days, and to spend 14 days in “home observation” upon arrival. The new restrictions have provoked fury on social media, with some questioning the government’s policy at a time when many people had hoped to go home. Nectar Gan, Lily Lee and David Culver report.

She’s one of Europe’s most powerful women. A vaccine spat could derail her big plans for the continent

ON OUR RADAR

TOP TIPS

No one would blame you for being in a depressed state about the coronavirus. There is, however, at least some cause for optimism. In the US, the number of people getting the coronavirus is falling, and the number of people getting vaccinated is rising. It will only continue to rise as more and more vaccines are made available.

Some parts of the US are beginning to reopen restaurants, even as Covid-19 is still transmitting at high rates. Last Friday, Los Angeles said its restaurants could reopen for outdoor dining with restrictions and 50% capacity. Chicago reopened with rules that encourage physical distancing and masks. New York announced restaurants could reopen at 25% capacity just in time for Valentine’s Day. It’s still safer to avoid indoor dining, but Dr. Anthony Fauci says it’s possible if it’s “done carefully.”

TODAY’S PODCAST

“I do have, you know, relatives who have expressed their concern to me about testing and being, quote unquote, lab rats as Black people for vaccines.” – Jamecka Britton, a Black nurse in Atlanta

“I think it’s really important that we start to advocate and reframe the concept of trying to protect pregnant women from research and really revisit that concept, as maybe we can better protect pregnant women by allowing them to participate in research and by generating data within the safe confines of a clinical trial.” — Dr. Emily S. Miller, obstetrician and member of the Society for Maternal-Fetal Medicine’s COVID-19 task force