Astra Zeneca vaccine waits for injection at the homeless accommodation YMCA in Romford, east London, Wednesday, Feb. 3, 2021. The British health service NHS England have started to vaccinate homeless ‘vulnerable’ people. In a study carried out but the Oxford University, the Astra Zeneca vaccine has been shown to stop also the transmission of the virus.(AP Photo/Frank Augstein)

Astra Zeneca vaccine waits for injection at the homeless accommodation YMCA in Romford, east London, Wednesday, Feb. 3, 2021. The British health service NHS England have started to vaccinate homeless ‘vulnerable’ people. In a study carried out but the Oxford University, the Astra Zeneca vaccine has been shown to stop also the transmission of the virus.(AP Photo/Frank Augstein)

Study finds COVID-19 vaccine may reduce virus transmission

It’s not clear what implications the AstraZeneca findings may have for other vaccines

AstraZeneca’s COVID-19 vaccine does more than prevent people from falling seriously ill — it appears to reduce transmission of the virus and offers strong protection for three months on just a single dose, researchers said Wednesday in an encouraging turn in the campaign to suppress the outbreak.

The preliminary findings from Oxford University, a co-developer of the vaccine, could vindicate the British government’s controversial strategy of delaying the second shot for up to 12 weeks so that more people can be quickly given a first dose. Up to now, the recommended time between doses has been four weeks.

The research could also bring scientists closer to an answer to one of the big questions about the vaccination drive: Will the vaccines actually curb the spread of the coronavirus?

It’s not clear what implications, if any, the findings might have for the two other major vaccines being used in the West, Pfizer’s and Moderna’s.

In the United States, Dr. Anthony Fauci, the nation’s top infectious disease expert, dismissed the idea of deliberately delaying second shots, saying the U.S. will “go by the science” and data from the clinical trials. The two doses of the Pifzer and Moderna vaccines are supposed to be given three and four weeks apart.

Still, the research appears to be good news in the desperate effort to arrest the spread of the virus and also suggests a way to ease vaccine shortages and get shots into more arms more quickly.

The makers of all three vaccines have said that their shots proved to be anywhere from 70% to 95% effective in clinical trials in protecting people from illness caused by the virus. But it was unclear whether the vaccines could also suppress transmission of the virus — that is, whether someone inoculated could still acquire the virus without getting sick and spread it to others.

As a result, experts have been saying that even people who have been vaccinated should continue to wear masks and keep their distance from others.

Oxford’s study, however, found that the vaccine not only prevented severe disease but appeared to cut transmission of the virus by two-thirds. The study has not been peer-reviewed yet.

Volunteers in the study underwent regular nasal swabs. The level of virus-positive swabs — from both those who had COVID-19 symptoms and those who had none – was 67% lower in the vaccinated group.

“That’s got to have a really beneficial effect on transmission,” Oxford lead researcher Sarah Gilbert said at a meeting of the New York Academy of Sciences.

The researchers also looked at how likely people who have been vaccinated are to get a symptom-free infection. In one subset of volunteers, there were 16 asymptomatic infections among the vaccinated and 31 in an unvaccinated comparison group.

Pfizer and Moderna also are studying the effect of their vaccines on asymptomatic infections.

Only the Pfizer and Moderna vaccines are being used in the United States. Britain is using both AstraZeneca’s and Pfizer’s. AstraZeneca’s has also been authorized by the 27-nation European Union. Pfizer has not endorsed the British government’s decision to lengthen the time between doses.

Mene Pangalos, executive vice-president of biopharmaceuticals research and development at AstraZeneca, said that no patients experienced severe COVID-19 or required hospitalization three weeks after receiving a first dose, and that effectiveness appeared to increase up to 12 weeks after the initial shot.

“Our data suggest you want to be as close to the 12 weeks as you can” for the second dose, Pangalos said.

British Health Secretary Matt Hancock said the study “backs the strategy that we’ve taken” to make sure more people have gotten at least one shot. Britain’s decision has been criticized as risky by other European countries.

Stephen Evans of the London School of Hygiene and Tropical Medicine said the study’s suggestion that a single dose protected people for 12 weeks was “useful but not definitive.”

He said that the authors themselves acknowledged their research was not designed to investigate the vaccine’s dosing schedule and that their conclusions were based on statistical modeling, not actual patients tracked over time.

“It certainly isn’t very strong evidence, but there is also no indication this is the wrong thing to do,” Evans said of Britain’s strategy.

One of the Oxford researchers, Dr. Andrew Pollard, said scientists also believe the AstraZeneca vaccine will continue to offer protection against new variants of COVID-19, though they are still waiting for data on that. Fast-spreading mutant versions have caused alarm around the world.

“If we do need to update the vaccines, then it is actually a relatively straightforward process. It only takes a matter of months, rather than the huge efforts that everyone went through last year to get the very large-scale trials run,” Pollard told the BBC.

Meanwhile, a U.N.-backed program to supply COVID-19 vaccines to the neediest people worldwide is gearing up after a troubled start. The COVAX Facility announced plans Wednesday for an initial distribution of some 100 million doses by the end of March and more than 200 million more by the end of June to dozens of countries.

READ MORE: Canada to get up to 1.1 m more doses by March through global vaccine alliance

Nearly all of the doses expected for the first phase are due to come from AstraZeneca and its partner, the Serum Institute of India. The rollout will be contingent on the World Health Organization authorizing the AstraZeneca shot for emergency use, which is expected to happen this month.

Some 190 countries and territories are participating in COVAX, which has seen rich nations scoop up vaccine supplies, sometimes at premium prices.

The pandemic’s worldwide death toll has eclipsed 2.2 million, including about 447,000 in the U.S., according to Johns Hopkins University data.

New cases per day in the U.S. and the number of Americans in the hospital with COVID-19 have dropped sharply in the past few weeks, but deaths are still running at close to all-time highs at an average of around 3,100 a day. Deaths often lag behind the infection curve, because it can take weeks to sicken and die from COVID-19.

As the Super Bowl approaches, Fauci is warning people against inviting others over for Super Bowl parties, urging viewers to “just lay low and cool it” to avoid turning Sunday’s big game into a super spreader event.

“You don’t want parties with people that you haven’t had much contact with,” he told NBC’s “Today” show. “You just don’t know if they’re infected.”

__

Associated Press reporters Jill Lawless, Maria Cheng, Jamey Keaten and Ricardo Alonso-Zaldivar and contributed to this report.

___

Danica Kirka And Lauran Neergaard, The Associated Press

Coronavirusvaccines

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Interior Health reported 33 new COVID-19 cases on March 5. (Black Press Files)
Interior Health reports 33 new COVID-19 cases on March 5

Over 300,000 vaccine doses have been administered provincewide.

Dave Wallace and David Askew with Askew’s Foods present a $500 cheque on March 2 to Chrissy Deye and Monica Kriese with the volunteer-run Food With Friends free lunch program. (Contributed)
Salmon Arm Food with Friends free lunch program receives support

Funds from Askew’s to help volunteers keep meals coming four days per week

Okanagan College, Vernon campus. (Brendan Shykora - Vernon Morning Star)
Student housing coming to Vernon, Salmon Arm

Province announces $66M for new student beds for Okanagan College campuses

A fire truck and police car park at the entrance to the Foreshore Trail about 6 p.m. on Thursday, March 4 as fire crews respond to a report of a fire farther down the trail and just above the railway tracks, between Lakeshore Road and the tracks. (Martha Wickett-Salmon Arm Observer)
Salmon Arm Fire Department quickly extinguishes fire above Foreshore Trail

Blaze started when man’s campfire catches fuel containers on fire

About 50 people gathered Friday, March 5, 2021 in Penticton to protest city council’s decision to close a temporary winter shelter. (Jesse Day - Western News)
WATCH: Protest over Penticton shelter draws large crowd

People are gathering in Gyro Park to protest the closure of a winter shelter

Malawian police guard AstraZeneca COVID-19 vaccines after the shipment arrived in Lilongwe, Malawi, Friday March 5, 2021. Canada is expecting its first shipments of AstraZeneca vaccine next week. (Associated Press/Thoko Chikondi)
B.C.’s daily COVID-19 cases climb to 634 Friday, four more deaths

Currently 255 people in hospital, 66 in intensive care

A crashed helicopter is seen near Mt. Gardner on Bowen Island on Friday March 5, 2021. Two people were taken to hospital in serious but stable condition after the crash. (Irene Paulus/contributed)
2 people in serious condition after helicopter goes down on Bowen Island

Unclear how many passengers aboard and unclear where the helicopter was going

Surrey Pretrial in Newton. (Photo: Tom Zytaruk)
B.C. transgender inmate to get human rights hearing after being held in mostly male jail

B.C. Human Rights Tribunal member Amber Prince on March 3 dismissed the pretrial’s application to have Makayla Sandve’s complaint dismissed

Supporters rally outside court as Pastor James Coates of GraceLife Church is in court to appeal bail conditions, after he was arrested for holding day services in violation of COVID-19 rules, in Edmonton, Alta., on Thursday March 4, 2021. THE CANADIAN PRESS/Jason Franson
‘Law remains valid:’ Pastor accused of violating health orders to remain in jail

The Justice Centre for Constitutional Freedoms is representing the pastor

Two shepherds on Queest Mountain pose for a photo in front of the A-Frame tent they camp out in while tending their flock in the year 1930. 
(Sicamous and District Historical Society photo)
Shuswap History in photos: Shepherds’ Camp

A pair of 1930s shepherds pose for a photo in the camp they called home while tending a flock.

Paramjit Bogarh, connected to the murder of his wife in Vernon 35 years ago, has been relerased on full parole, one year after he was sentenced to five years in prison for accessory after the fact. (Contributed)
Full parole for ex-Okanagan man who helped wife’s alleged killer escape

Paramjit Bogarh pleaded guilty to accessory to murder after helping brother flee Canada

The Princeton Traditional Music Festival, normally held in August, was denied a grant due to COVID. (File photo)
COVID makes some of the 2021 grant decisions for Princeton council

Municipality doles out funds while striving to meet policy

The Netflix logo on an iPhone. B.C. delayed imposing sales tax on digital services and sweetened carbonated beverages as part of its response to COVID-19. Those taxes take effect April 1, 2021. THE CANADIAN PRESS/AP, Matt Rourke
B.C. applies 7% sales tax on streaming, vaping, sweet drinks April 1

Measures from 2020 budget were delayed due to COVID-19

Most Read