This is the weekly edition of CNN’s coronavirus newsletter. Look out for your roundup every Wednesday. If you haven’t subscribed yet, sign up here.

CNN  — 

You may need up to three Covid-19 vaccine doses to be considered fully vaccinated.

Waning vaccine immunity and rising infections due to the Delta variant has prompted wealthy nations to reconsider the definition of “fully vaccinated” – which usually means two Covid-19 jabs.

UK Prime Minister Boris Johnson admitted as much on Monday, saying boosters were vital to prevent pandemic restrictions from being reintroduced. “It’s very clear that getting three jabs – getting your booster – will become an important fact and it will make life easier for you in all sorts of ways,” he told a press conference.

Other European nations are moving towards mandates on booster jabs. By December 15, anyone over the age of 65 will need a third dose to revalidate their vaccination pass in France, President Emmanuel Macron announced last week. In Austria, full vaccination status expires after nine months of the second dose, which in effect enforces booster doses. In Israel, unless you received your second dose of the Covid-19 vaccine within the last six months, you now need a third dose to become eligible for a green pass, which allows entry to gyms, restaurants and other venues.

Global health experts fear reliance on boosters is affecting the supply of initial doses in low-income nations, where just 4.6% have received an injection. World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus said it was “a scandal” that six times more booster shots are being administered around the world daily than primary doses in low-income countries.

“It makes no sense to give boosters to healthy adults, or to vaccinate children, when health workers, older people and other high-risk groups around the world are still waiting for their first dose,” he warned last Friday.

The supply of vaccines is being prioritized for rich nations, which have pushed themselves to the front of the queue by paying drug companies higher prices, Anna Marriott, health policy adviser for Oxfam, told a UK parliamentary group on coronavirus on Tuesday. “If we look at low-income countries as a whole, less than 1% of the total vaccine supply has been delivered to those poorest countries, many of which are in Africa,” she added.

It’s also a gamble for rich nations to rely on vaccinations in a pandemic, Dr. David Nabarro, WHO’s special envoy on Covid-19, told UK lawmakers. “It has never been done before and it would really be an inappropriate public health strategy to do so,” he said. With so much yet to be learned about the virus, using vaccines as the main weapon against Covid-19 could lead to new variants, Nabarro warned.

What needs to be done is a “combination approach” of masks and other health interventions, “which is to do everything possible to empower people to avoid being infected by the pathogen,” he said.

YOU ASKED. WE ANSWERED.

Q: When will the Pfizer Covid-19 vaccine booster be available for all adults in the US?

A: On Tuesday, the US Food and Drug Administration (FDA) confirmed its vaccine advisers will not be convened to consider the requested amendment to the booster’s emergency use authorization – which means the decision could come any time. 

“While the FDA cannot predict how long its evaluation of the data and information will take, the agency will review the request as expeditiously as possible,” FDA spokesperson Alison Hunt told CNN. 

The US Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices will meet Friday to discuss expanding booster eligibility for Pfizer’s Covid-19 vaccine, a CDC spokesperson told CNN Tuesday. CDC’s vaccine advisers typically meet only once a vaccine has received authorization from the FDA.  

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.

READS OF THE WEEK

The corgi was killed in its home by Covid prevention workers while its owner was under quarantine at a nearby hotel.

The killing of a corgi shows how government power has grown unchecked in China in the name of Covid prevention

A corgi was killed in its home by Covid prevention workers in the Chinese city of Shangrao, in southeastern Jiangxi province, on Friday, while the dog’s owner was undergoing compulsory quarantine in a nearby hotel, Nectar Gan and Steve George report.

The killing of the dog, which triggered a massive outcry on Chinese social media, is the latest example of the extreme measures taken by local authorities in China in pursuit of zero-Covid during a renewed Delta variant outbreak.

Amid the outpouring of shock and anger, the dog’s death has sparked heated debate about animal rights, as well as reflection on how far government power can be expanded during the pandemic at the expense of individual rights.

Biden administration set to purchase Pfizer’s experimental antiviral pill

The Biden administration intends to purchase 10 million doses of Pfizer’s experimental antiviral Covid-19 pill and is finalizing the contract now, according to a source familiar with the plans. The announcement could come as soon as this week, Kaitlin Collins reports.

The administration had initially planned to purchase about 5 million doses, but after seeing Pfizer’s data, President Joe Biden wanted to double the order, the source told CNN on Tuesday

The pill is to be administered in combination with an older antiviral drug called ritonavir and is meant to treat mild to moderate Covid-19 in patients at increased risk of hospitalization or death, the company has said. Pfizer is seeking emergency use authorization from the FDA for the pill and said Tuesday that it has signed a licensing agreement to allow for broader global access to it.

Austria imposes lockdown for the unvaccinated as Europe turns the screws on them

A lockdown specifically targeting the unvaccinated came into force in Austria on Monday. It bans uninoculated people – more than a third of the country’s population – from leaving their homes except for a few specific reasons, Rob Picheta reports

The new rules reflect growing exasperation across much of the European Union about those who continue to refuse a vaccination. Germany, home to one of the lowest vaccination rates in Western Europe, may become the next country to impose stricter rules. 

Proposed measures would require Germans to provide proof of vaccination or a negative test in order to ride a bus or board a train, in an expansion of the country’s “3G” system that requires one or the other to enter certain venues and settings. 

TOP TIP

Get vaccinated if you want to enjoy New Year’s Eve in Times Square 

New York City will once again welcome thousands of people to Times Square for the famed New Year’s Eve ball drop tradition, so long as they can show proof of vaccination against Covid-19, officials said Tuesday. 

The head of the Times Square Alliance, Tom Harris, said that all attendees five years and older will have to show proof of vaccination. Those attending with disabilities who cannot be vaccinated must show proof of a negative PCR test within 72 hours. He added that children under five must be accompanied by a vaccinated adult and all individuals who are unable to be vaccinated must wear a mask. Read more here. 

TODAY’S PODCAST

In today’s episode, CNN Chief Medical Correspondent Dr. Sanjay Gupta heads into the kitchen to explore how food can be a powerful tonic for our bodies and minds. Listen Now.