Delaying second Pfizer shot to 12 weeks produces three times more COVID antibodies in older people: study

Older people who receive their second shot of Pfizer’s coronavirus vaccine 12 weeks after the first dose produce 3½ times more antibodies than those who wait just three weeks, according to a British study published Friday.

The study, conducted by the University of Birmingham in partnership with Public Health England, marks the first direct comparison of the two vaccine intervals since the U.K. moved to extend the wait to 12 weeks so vulnerable people could have their first shot quicker.

Researchers analyzed blood samples from 175 people older than 80 and found that peak antibody responses were “markedly enhanced” in those who waited longer for their second shot, said Dr. Helen Parry, a Birmingham professor and lead author of the study.

“This research is crucial, particularly in older people, as immune responses to vaccination deteriorate with age,” she said in a statement. “Understanding how to optimize COVID-19 vaccine schedules and maximize immune responses within this age group is vitally important.”

In this Dec. 8, 2020 file photo, a nurse prepares to administer the Pfizer-BioNTech COVID-19 vaccine at Guy's Hospital in London.
In this Dec. 8, 2020 file photo, a nurse prepares to administer the Pfizer-BioNTech COVID-19 vaccine at Guy's Hospital in London.


In this Dec. 8, 2020 file photo, a nurse prepares to administer the Pfizer-BioNTech COVID-19 vaccine at Guy's Hospital in London. (Frank Augstein/)

FDA authorizes Pfizer’s COVID vaccine for adolescents 12 to 15 years old

The vaccine developed by Pfizer and Germany’s BioNTech was originally authorized for a three-week window between two doses, which is still the method followed in the U.S. However, the U.K. and several other countries struggling with limited supplies expanded the interval to 12 weeks to allow more people to have some protection against the virus as soon as possible.

The controversial move sparked widespread criticism from doctors and experts from around the world. The British Medical Association scolded the U.K. government in January, saying the decision was “difficult to justify” given the lack of data supporting the longer vaccine gap.

Pfizer also weighed in at the time and said its clinical trials last year were designed to evaluate the vaccine’s efficacy and safety following a 21-day window between each dose. On Friday, the company said it could only comment on its recommended vaccine regimen, which is up to 95% effective against COVID-19.

Irish Prime Minister Micheal Martin (L) bumps elbows with Brenda Dillon, assistant director of nursing at Health Service Executive (HSE), after receiving his first dose of the AstraZeneca/Oxford vaccine against coronavirus at the vaccination center at City Hall in Cork on May 9, 2021.
Irish Prime Minister Micheal Martin (L) bumps elbows with Brenda Dillon, assistant director of nursing at Health Service Executive (HSE), after receiving his first dose of the AstraZeneca/Oxford vaccine against coronavirus at the vaccination center at City Hall in Cork on May 9, 2021.
A sign offers fans free tickets to a future game if they get a COVID-19 vaccine offered at the stadium prior to the game between the New York Yankees and the Washington Nationals at Yankee Stadium on May 9, 2021, in the Bronx borough of New York City. New York Governor Andrew Cuomo announced this COVID vaccine initiative on May 5.
A sign offers fans free tickets to a future game if they get a COVID-19 vaccine offered at the stadium prior to the game between the New York Yankees and the Washington Nationals at Yankee Stadium on May 9, 2021, in the Bronx borough of New York City. New York Governor Andrew Cuomo announced this COVID vaccine initiative on May 5.
Medical personnel conducts COVID-19 vaccinations for people, offering the Sinovac and AstraZeneca vaccine shots, at the Holy Redeemer Catholic church compound in Bangkok, Thailand on May 9, 2021.
Medical personnel conducts COVID-19 vaccinations for people, offering the Sinovac and AstraZeneca vaccine shots, at the Holy Redeemer Catholic church compound in Bangkok, Thailand on May 9, 2021.
A local resident receives a vaccination with AstraZeneca against COVID-19 inside the city's main mosque, which has temporarily become a mass vaccination center, during the coronavirus pandemic on May 9, 2021, in Cologne, Germany.
A local resident receives a vaccination with AstraZeneca against COVID-19 inside the city's main mosque, which has temporarily become a mass vaccination center, during the coronavirus pandemic on May 9, 2021, in Cologne, Germany.
People stand in a queue as they wait to get a dose of the Chinese-made Sinopharm COVID-19 vaccine in Panadura, a suburb of Sri Lanka's capital Colombo, on May 8, 2021.
People stand in a queue as they wait to get a dose of the Chinese-made Sinopharm COVID-19 vaccine in Panadura, a suburb of Sri Lanka's capital Colombo, on May 8, 2021.
A medical staff vaccinates a man during the vaccination marathon organized at the "Bran Castle" in Bran village on May 8, 2021. Romanian authorities organized a non-stop vaccination marathon in several locations, and Bucharest, to offer the people an opportunity to get vaccinated without prior appointment, hoping to increase the appetite of the population for the vaccines against COVID-19. Since the beginning of the vaccination campaign, 3,580,368 people have been vaccinated, of which 2,311,487 have received both doses of vaccine. "Bran Castle" is located in the central Transylvania region of Romania.
Representative Alexandria Ocasio-Cortez (D-NY) is joined by New York Mayor Bill de Blasio as they visit a mobile vaccination site in the Bronx on Friday afternoon on May 7, 2021, in New York City. The Bronx, along with parts of Brooklyn and Staten Island, is one of the areas that has seen some resistance to getting the vaccine for COVID-19. The Bronx is also the borough that had the highest death rate from the pandemic.
An NYC Mobile Vaccine Clinic bus is seen parked on Seventh Ave. and 54th St. in Brooklyn early Wednesday, April 7, 2021. The bus can give out 150-200 doses of the Johnson & Johnson vaccine a day and will be used to reach the city's most vulnerable populations.
An NYC Mobile Vaccine Clinic bus is seen parked on Seventh Ave. and 54th St. in Brooklyn early Wednesday, April 7, 2021. The bus can give out 150-200 doses of the Johnson & Johnson vaccine a day and will be used to reach the city's most vulnerable populations.
An NYC Mobile Vaccine Clinic bus is seen parked on Seventh Ave. and 54th St. in Brooklyn early Wednesday, April 7, 2021.
An NYC Mobile Vaccine Clinic bus is seen parked on Seventh Ave. and 54th St. in Brooklyn early Wednesday, April 7, 2021.
Cristian Obretin, a Peter Lugo Restaurant worker, displays his CDC Vaccination Card after being vaccinated on an NYC Mobile Vaccine Clinic bus parked on Seventh Ave. and 54th St. in Brooklyn early Wednesday, April 7, 2021.
Cristian Obretin, a Peter Lugo Restaurant worker, displays his CDC Vaccination Card after being vaccinated on an NYC Mobile Vaccine Clinic bus parked on Seventh Ave. and 54th St. in Brooklyn early Wednesday, April 7, 2021.
People line up outside a public ambulatory as they wait to receive a dose of the AstraZeneca vaccine in Barcelona, Spain, Tuesday, April 6, 2021. Spanish Prime Minister Pedro Sánchez says a steep rise in vaccine deliveries over the coming months will allow the country to inoculate 70% of its adult population against COVID-19 by the end of August. That's some 33 million people. He said Tuesday that Spain expects to receive 87 million doses by September.
A Palestinian school teacher receives a shot of the Oxford-AstraZeneca COVID-19 vaccine at an elementary school in the West Bank city of Ramallah, Palestine on Tuesday, April 6, 2021. The Palestinian Authority launched a campaign to vaccinate school teachers, an initial step in its plan to return the elementary level students to schools next week. The West Bank is under lockdown measures due to a surge in COVID-19 cases.
People queue as they arrive at the Stade de France stadium to be vaccinated against COVID-19 in Saint-Denis, outside Paris, Tuesday, April 6, 2021. While France remains far behind Britain and the United States in terms of vaccinating its population, the pace is starting to pick up.
People queue as they arrive at the Stade de France stadium to be vaccinated against COVID-19 in Saint-Denis, outside Paris, Tuesday, April 6, 2021. While France remains far behind Britain and the United States in terms of vaccinating its population, the pace is starting to pick up.
People queue up outside a vaccination center for BioNTech in Hong Kong on Tuesday, April 6, 2021. Hong Kong has resumed administering the vaccine developed by Pfizer and BioNTech in the city on Monday, following a 12-day suspension after packaging defects were detected in a batch of the shots.
People queue up outside a vaccination center for BioNTech in Hong Kong on Tuesday, April 6, 2021. Hong Kong has resumed administering the vaccine developed by Pfizer and BioNTech in the city on Monday, following a 12-day suspension after packaging defects were detected in a batch of the shots.
Workers sit in the observation area after receiving a one shot dose of the Johnson & Johnson COVID-19 vaccine at a clinic geared toward agriculture workers organized by TODEC on April 5, 2021, in Riverside, Calif. TODEC Legal Center is an immigrant advocacy organization that is traveling to agriculture sites in Southern California to educate and vaccinate farmworkers while dispelling myths about the vaccines. Essential agriculture workers are among the most likely to contract COVID in California as they often work closely together, lack health insurance and reside in crowded housing conditions.
A healthcare worker administers a dose of the Sinovac Biotech Ltd. Covid-19 vaccine to a man in a vehicle during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia. Indonesia has begun its mass vaccination program in earnest, using the Sinovac Biotech Ltd. Covid-19 vaccine developed by China.
Jose Ortiz receives a one-shot dose of the Johnson & Johnson COVID-19 vaccine at a clinic geared toward agriculture workers organized by TODEC on April 5, 2021, in Riverside, Calif.
Jose Ortiz receives a one-shot dose of the Johnson & Johnson COVID-19 vaccine at a clinic geared toward agriculture workers organized by TODEC on April 5, 2021, in Riverside, Calif.
Leanne Montenegro, 21, covers her eyes as she doesn't like the sight of needles, while she receives the Pfizer COVID-19 vaccine at a FEMA vaccination center at Miami Dade College on Monday, April 5, 2021, in Miami, Fla. Any adult in Florida is now eligible to receive the coronavirus vaccine. In addition, the state announced that teens ages 16 and 17 can also get the vaccine with parental permission.
Matthew Dickens, 21, left, from St. Petersburg, gets his first vaccine as it was administered by RN Arlene Keys, at the Central Pinellas vaccine site in Largo, Fla. on Monday, April 5, 2021. "Quick and easy, I barely felt it," Dickens said. "I was in and out." Floridians 18 and over can now get the Pfizer, Moderna or Johnson & Johnson vaccines, while 16- and 17-year-olds will be able to get the Pfizer shot.
In this photo provided by the State of Vermont, Vermont Gov. Phil Scott, center, receives a COVID-19 vaccine as his wife, Diana McTeague Scott, right, looks on, Monday, April 5, 2021, at Montpelier High School in Montpelier, Vt. Scott, a Republican, and his wife got the single-dose Johnson & Johnson shot at a state-run clinic at the school.
In this photo provided by the State of Vermont, Vermont Gov. Phil Scott, center, receives a COVID-19 vaccine as his wife, Diana McTeague Scott, right, looks on, Monday, April 5, 2021, at Montpelier High School in Montpelier, Vt. Scott, a Republican, and his wife got the single-dose Johnson & Johnson shot at a state-run clinic at the school.
Tyler Rorah, 18, of Brooksville, receives a Moderna COVID-19 vaccine shot from LPN Sonie Woods, right, during his vaccination appointment on Monday, April 5, 2021, at Saint Leo University, which is serving as the host for the Florida Department of Health's COVID-19 vaccine distribution for East Pasco County.
Tyler Rorah, 18, of Brooksville, receives a Moderna COVID-19 vaccine shot from LPN Sonie Woods, right, during his vaccination appointment on Monday, April 5, 2021, at Saint Leo University, which is serving as the host for the Florida Department of Health's COVID-19 vaccine distribution for East Pasco County.
People wait in line to receive a COVID-19 vaccine at a FEMA vaccination center at Miami Dade College on Monday, April 5, 2021, in Miami.
People wait in line to receive a COVID-19 vaccine at a FEMA vaccination center at Miami Dade College on Monday, April 5, 2021, in Miami.
A healthcare worker administers a dose of the Sinovac Biotech Ltd. COVID-19 vaccine to a man on a motorcycle during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia.
A healthcare worker administers a dose of the Sinovac Biotech Ltd. COVID-19 vaccine to a man on a motorcycle during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia.
A man wearing a Javanese traditional costume receives a dose of the Sinovac Biotech Ltd. Covid-19 vaccine in a vehicle during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia.
A man wearing a Javanese traditional costume receives a dose of the Sinovac Biotech Ltd. Covid-19 vaccine in a vehicle during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia.
Healthcare workers administer doses of the Sinovac Biotech Ltd. COVID-19 vaccine during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia.
Healthcare workers administer doses of the Sinovac Biotech Ltd. COVID-19 vaccine during a mass drive-thru vaccination program at the Prambanan temple complex on April 5, 2021, in Yogyakarta, Indonesia.
Francis, 90, lays on a stretcher as his wife Josette, 87, waits after receiving the Pfizer/BioNTech vaccine in a gymnasium in Nogent-le-Rotrou, western France, on April 3, 2021. 770 second doses are expected to be administered during a flash vaccination day.
Francis, 90, lays on a stretcher as his wife Josette, 87, waits after receiving the Pfizer/BioNTech vaccine in a gymnasium in Nogent-le-Rotrou, western France, on April 3, 2021. 770 second doses are expected to be administered during a flash vaccination day.
Nuns Tomasa Lopez, 71, left, and Maria Lopez, 79,  fill out forms before receiving a second dose of the Sinovac COVID-19 vaccine at the Americas Cultural Center in Ecatepec, Mexico, Saturday, April 3, 2021.
Nuns Tomasa Lopez, 71, left, and Maria Lopez, 79, fill out forms before receiving a second dose of the Sinovac COVID-19 vaccine at the Americas Cultural Center in Ecatepec, Mexico, Saturday, April 3, 2021.
A patient receives an injection of the Moderna Covid-19 vaccine on the opening day of a mass vaccination center set up in the OL Group's Groupama Stadium in Decines-Charpieu, France on April 3, 2021.
A patient receives an injection of the Moderna Covid-19 vaccine on the opening day of a mass vaccination center set up in the OL Group's Groupama Stadium in Decines-Charpieu, France on April 3, 2021.
Filipino nurse Monette Villaraza gets China's Sinovac vaccine for COVID-19 under a government program at a school in Quezon City, Philippines on Tuesday, March 30, 2021. Philippine officials placed Metropolitan Manila and four outlying provinces, a region of more than 25 million people, back to a lockdown Monday at the height of the Lenten and Easter holiday travel season as they scrambled to control an alarming surge in coronavirus infections.
A guard stands in front of a COVID-19 vaccination location on March 29, 2021, in the Brooklyn borough of New York City. As New York’s positivity rate slowly climbs, Governor Andrew Cuomo has announced that New Yorkers 30 years of age and older will be vaccine-eligible starting Tuesday.
A guard stands in front of a COVID-19 vaccination location on March 29, 2021, in the Brooklyn borough of New York City. As New York’s positivity rate slowly climbs, Governor Andrew Cuomo has announced that New Yorkers 30 years of age and older will be vaccine-eligible starting Tuesday.
A health care worker steps out of a mobile vaccination van parked on a street corner in the Sunset Park neighborhood of Brooklyn, Monday, March 29, 2021, in New York. As part of New York City's ongoing efforts to increase access to the COVID-19 vaccine citywide, NYC Test & Trace Corps added mobile vaccination to its community vaccine clinic program Monday, launching this clinic-on-wheels with community partners Mixteca, a community organization serving Spanish-speaking and indigenous people in Brooklyn. The van is part of a pilot program. Officials say more vans will be announced as the program rolls out.
A health care worker, left, registers Immanuel Balico and his wife Nereyda Garcia for COVID-19 vaccinations on the street near a mobile vaccination van providing the vaccine in the Sunset Park neighborhood of Brooklyn, Monday, March 29, 2021, in New York. Balico and Garcia were getting the one-dose Johnson & Johnson vaccine through a partnership between NYC Test & Trace Corps and Mixteca, a community-based organization serving Spanish-speaking and indigenous Latin Americans in the area.
Jessica Flores gets her second dose of the Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas. Texas has opened up all vaccination eligibility to all adults starting today.
Jessica Flores gets her second dose of the Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas. Texas has opened up all vaccination eligibility to all adults starting today.
A worker takes the temperature of a patient at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
A worker takes the temperature of a patient at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
Patients are observed for fifteen minutes after being vaccinated at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas. Texas has had a slower rollout than some states and with the increase in eligibility as leaders are hoping more and more citizens get vaccinated.
Patients are observed for fifteen minutes after being vaccinated at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas. Texas has had a slower rollout than some states and with the increase in eligibility as leaders are hoping more and more citizens get vaccinated.
Rene Neira receives his Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
Rene Neira receives his Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
Kelly Russell takes the temperature of a patient at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
Kelly Russell takes the temperature of a patient at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
A nurse fills up a syringe with the Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
A nurse fills up a syringe with the Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
A patient receives his first dose of the Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
A patient receives his first dose of the Moderna COVID-19 vaccine at a vaccination site at a senior center on March 29, 2021, in San Antonio, Texas.
A Palestinian man who works in Israel receives the first dose of a Moderna COVID-19 vaccine by an Israeli medical worker in Meitar crossing checkpoint between the West Bank and Israel on March 9, 2021, in Meitar, Israel.
A Palestinian man who works in Israel receives the first dose of a Moderna COVID-19 vaccine by an Israeli medical worker in Meitar crossing checkpoint between the West Bank and Israel on March 9, 2021, in Meitar, Israel.
Palestinians who work in Israel wait in line to receive the first dose of a Moderna COVID-19 vaccine by Israeli medical workers in the Meitar crossing checkpoint between the West Bank and Israel on March 9, 2021, in Meitar, Israel. More than two months after starting a world-leading COVID-19 vaccination campaign for its own citizens, Israel began administering the Moderna vaccine to Palestinian laborers from the West Bank who enter Israel or Israeli settlements for work. More than 100,000 Palestinians work in the country and its settlements.
A Palestinian man who works in Israel receives the first dose of a Moderna COVID-19 vaccine by an Israeli medical worker in Meitar crossing checkpoint between the West Bank and Israel on March 9, 2021, in Meitar, Israel.
A Palestinian man who works in Israel receives the first dose of a Moderna COVID-19 vaccine by an Israeli medical worker in Meitar crossing checkpoint between the West Bank and Israel on March 9, 2021, in Meitar, Israel.
Vaccination booths and signage are pictured inside a South Auckland vaccination clinic on March 09, 2021, in Auckland, New Zealand. New Zealand's first large-scale COVID-19 vaccination clinic is opening in Auckland, with border workers' families the first of the wider New Zealand public to receive their coronavirus vaccinations.
Vaccination booths and signage are pictured inside a South Auckland vaccination clinic on March 09, 2021, in Auckland, New Zealand. New Zealand's first large-scale COVID-19 vaccination clinic is opening in Auckland, with border workers' families the first of the wider New Zealand public to receive their coronavirus vaccinations.
New York Gov. Andrew Cuomo greets service members as he leaves a vaccination site at the Jacob K. Javits Convention Center on March 8, 2021, in New York City. Cuomo has been called to resign from his position after allegations of sexual misconduct were brought against him.
New York Gov. Andrew Cuomo greets service members as he leaves a vaccination site at the Jacob K. Javits Convention Center on March 8, 2021, in New York City. Cuomo has been called to resign from his position after allegations of sexual misconduct were brought against him.
Health workers prepare to give Antonio Ferrari (92) a dose of the Pfizer-BioNTech COVID-19 vaccine at his house in Lima on March 8, 2021, as Peru starts vaccination of the elderly, police and military.
Health workers prepare to give Antonio Ferrari (92) a dose of the Pfizer-BioNTech COVID-19 vaccine at his house in Lima on March 8, 2021, as Peru starts vaccination of the elderly, police and military.
Residents wait 15 minutes after receiving a Pfizer vaccine during a COVID-19 vaccination campaign in Pamplona, northern Spain, Tuesday, March 2, 2021. The Navarra regional government has called around 3,400 residents of the city over the age of 80 to be vaccinated against COVID-19.
Residents wait 15 minutes after receiving a Pfizer vaccine during a COVID-19 vaccination campaign in Pamplona, northern Spain, Tuesday, March 2, 2021. The Navarra regional government has called around 3,400 residents of the city over the age of 80 to be vaccinated against COVID-19.
Iraqi health personnel wait to receive a coronavirus vaccine at a clinic in Baghdad, Iraq on Tuesday, March 2, 2021.
Iraqi health personnel wait to receive a coronavirus vaccine at a clinic in Baghdad, Iraq on Tuesday, March 2, 2021.
People wait in line to receive a dose of the Chinese Sinopharm COVID-19 vaccine at Belgrade Fair makeshift vaccination center in Belgrade, Serbia, on Wednesday, Feb. 17, 2021. Serbian health expert Chief epidemiologist Predrag Kon on Tuesday, March 2, 2021, called for the government to introduce a state of emergency and a strict lockdown to halt a surge in coronavirus infections in the Balkan country.
An employee with the McKesson Corporation packs a box of the Johnson and Johnson COVID-19 vaccine into a cooler for shipping from their facility in Shepherdsville, Ky. on Monday, March 1, 2021.
An employee with the McKesson Corporation packs a box of the Johnson and Johnson COVID-19 vaccine into a cooler for shipping from their facility in Shepherdsville, Ky. on Monday, March 1, 2021.
Health-care workers walk through the post-vaccine waiting area at a mass COVID-19 vaccination clinic for Peel Region in Mississauga, Ontario on Monday, March 1, 2021.
Health-care workers walk through the post-vaccine waiting area at a mass COVID-19 vaccination clinic for Peel Region in Mississauga, Ontario on Monday, March 1, 2021.
People wait in line at a COVID-19 vaccine clinic at Olympic Stadium marking the beginning of mass vaccination in the Province of Quebec based on age in Montreal on Monday, March 1, 2021.
People wait in line at a COVID-19 vaccine clinic at Olympic Stadium marking the beginning of mass vaccination in the Province of Quebec based on age in Montreal on Monday, March 1, 2021.
Cars line up in a parking lot at NRG Park as people wait to receive a COVID-19 vaccine at a federally-supported supersite at the Harris County facility on Wednesday, Feb. 24, 2021, in Houston, Tex.
Cars line up in a parking lot at NRG Park as people wait to receive a COVID-19 vaccine at a federally-supported supersite at the Harris County facility on Wednesday, Feb. 24, 2021, in Houston, Tex.
This photograph released by UNICEF on Wednesday, Feb. 24, 2021, shows the first shipment of COVID-19 vaccines distributed by the COVAX Facility arriving at the Kotoka International Airport in Accra, Ghana. Ghana has become the first country in the world to receive vaccines acquired through the United Nations-backed COVAX initiative with a delivery of 600,000 doses of the AstraZeneca vaccine made by the Serum Institute of India.
This photograph released by UNICEF on Wednesday, Feb. 24, 2021, shows the first shipment of COVID-19 vaccines distributed by the COVAX Facility arriving at the Kotoka International Airport in Accra, Ghana.
This photograph released by UNICEF on Wednesday, Feb. 24, 2021, shows the first shipment of COVID-19 vaccines distributed by the COVAX Facility arriving at the Kotoka International Airport in Accra, Ghana.
This photograph released by UNICEF on Wednesday, Feb. 24, 2021, shows the first shipment of COVID-19 vaccines distributed by the COVAX Facility arriving at the Kotoka International Airport in Accra, Ghana. Ghana has become the first country in the world to receive vaccines acquired through the United Nations-backed COVAX initiative with a delivery of 600,000 doses of the AstraZeneca vaccine made by the Serum Institute of India.
Primarily Navy personnel prepare for the opening of a mass vaccination site in the Queens borough of New York on Wednesday, Feb. 24, 2021. This FEMA-run site, along with another in Brooklyn, gives priority to local residents in an effort to equitably distribute the vaccine.
Primarily Navy personnel prepare for the opening of a mass vaccination site in the Queens borough of New York on Wednesday, Feb. 24, 2021. This FEMA-run site, along with another in Brooklyn, gives priority to local residents in an effort to equitably distribute the vaccine.
Navy personnel prepare doses of the COVID-19 vaccine before the opening of a mass vaccination site in the Queens borough of New York on Wednesday, Feb. 24, 2021.
Navy personnel prepare doses of the COVID-19 vaccine before the opening of a mass vaccination site in the Queens borough of New York on Wednesday, Feb. 24, 2021.
Motorists line up at a COVID-19 vaccination site at Dodger Stadium on Tuesday, Feb. 23, 2021, in Los Angeles, Calif.
Motorists line up at a COVID-19 vaccination site at Dodger Stadium on Tuesday, Feb. 23, 2021, in Los Angeles, Calif.
Motorists line up at a COVID-19 vaccination site at Dodger Stadium on Tuesday, Feb. 23, 2021, in Los Angeles, Calif.
Motorists line up at a COVID-19 vaccination site at Dodger Stadium on Tuesday, Feb. 23, 2021, in Los Angeles, Calif.
Prime Minister Prayuth Chan-ocha holds samples of Sinovac vaccine during a ceremony to mark the arrival of 200,000 doses of the Sinovac vaccine at Suvarnabhumi airport in Bangkok, Thailand on Wednesday, Feb. 24, 2021. Thailand is scheduled to receive the first shipments of 200,000 doses of the Sinovac vaccine and 117,000 doses of the AstraZeneca vaccine on Feb. 24.
Marta Galmariz Levy sits with her husband Víctor Levy, 86, as he waits to get a shot of the AstraZeneca vaccine for COVID-19 in Buenos Aires, Argentina on Wednesday, Feb. 24, 2021, as the capital vaccinates people over the age of 80 for the new coronavirus.
Marta Galmariz Levy sits with her husband Víctor Levy, 86, as he waits to get a shot of the AstraZeneca vaccine for COVID-19 in Buenos Aires, Argentina on Wednesday, Feb. 24, 2021, as the capital vaccinates people over the age of 80 for the new coronavirus.
Malaysia's Prime Minister Muhyiddin Yassin receives the first dose of the Pfizer-BioNTech COVID-19 vaccine at a clinic in Putrajaya, Malaysia on Wednesday, Feb. 24, 2021.
Malaysia's Prime Minister Muhyiddin Yassin receives the first dose of the Pfizer-BioNTech COVID-19 vaccine at a clinic in Putrajaya, Malaysia on Wednesday, Feb. 24, 2021.
People wait for their Sinovac Biotech COVID-19 vaccine at the Americas sports center in Ecatepec, a borough on the outskirts of Mexico City, on Tuesday, Feb. 23, 2021.
People wait for their Sinovac Biotech COVID-19 vaccine at the Americas sports center in Ecatepec, a borough on the outskirts of Mexico City, on Tuesday, Feb. 23, 2021.
Tokyo Medical Center director Kazuhiro Araki, left, receives a dose of COVID-19 vaccine in Tokyo on Wednesday, Feb. 17, 2021.
Tokyo Medical Center director Kazuhiro Araki, left, receives a dose of COVID-19 vaccine in Tokyo on Wednesday, Feb. 17, 2021.
Tokyo Medical Center director Kazuhiro Araki speaks to the media after receiving a dose of the COVID-19 vaccine in Tokyo on Wednesday, Feb. 17, 2021. Japan's first coronavirus shots were given to health workers Wednesday, beginning a vaccination campaign considered crucial to holding the already delayed Tokyo Olympics.
Tokyo Medical Center director Kazuhiro Araki speaks to the media after receiving a dose of the COVID-19 vaccine in Tokyo on Wednesday, Feb. 17, 2021. Japan's first coronavirus shots were given to health workers Wednesday, beginning a vaccination campaign considered crucial to holding the already delayed Tokyo Olympics.
A medical worker receives a dose of the COVID-19 vaccine at Tokyo Medical Center in Tokyo on Wednesday, Feb. 17, 2021.
A medical worker receives a dose of the COVID-19 vaccine at Tokyo Medical Center in Tokyo on Wednesday, Feb. 17, 2021.
A medical worker receives a dose of the COVID-19 vaccine at Tokyo Medical Center in Tokyo on Wednesday, Feb. 17, 2021. J
A medical worker receives a dose of the COVID-19 vaccine at Tokyo Medical Center in Tokyo on Wednesday, Feb. 17, 2021. J
South African President Cyril Ramaphosa receives a Johnson and Johnson COVID-19 vaccine in Khayelitsha, Cape Town, South Africa on Wednesday, Feb. 17, 2021. Ramaphosa was among the first in his country to receive the vaccination to launch the inoculation drive in the country.
South African President Cyril Ramaphosa receives a Johnson and Johnson COVID-19 vaccine in Khayelitsha, Cape Town, South Africa on Wednesday, Feb. 17, 2021. Ramaphosa was among the first in his country to receive the vaccination to launch the inoculation drive in the country.
Health care workers look through a window at a hospital in Khayelitsha, Cape Town, South Africa during the rollout of the first batch of Johnson and Johnson vaccines in the country. South African President Cyril Ramaphosa was among the first in his country to receive a COVID-19 vaccination to launch the inoculation drive.
Health care workers look through a window at a hospital in Khayelitsha, Cape Town, South Africa during the rollout of the first batch of Johnson and Johnson vaccines in the country. South African President Cyril Ramaphosa was among the first in his country to receive a COVID-19 vaccination to launch the inoculation drive.
A man gets the coronavirus vaccine shot at an outdoor vaccination site at Lakewood Ranch on Wednesday, Feb. 17, 2021, in Bradenton, Fla.
A man gets the coronavirus vaccine shot at an outdoor vaccination site at Lakewood Ranch on Wednesday, Feb. 17, 2021, in Bradenton, Fla.
Medical workers attend training to learn how to give coronavirus vaccine shots at the Korean Nurses Association in Seoul, South Korea on Wednesday, Feb. 17, 2021. South Korea plans to start coronavirus inoculations on Feb. 26 with AstraZeneca's COVID-19 vaccine.
Medical workers attend training to learn how to give coronavirus vaccine shots at the Korean Nurses Association in Seoul, South Korea on Wednesday, Feb. 17, 2021. South Korea plans to start coronavirus inoculations on Feb. 26 with AstraZeneca's COVID-19 vaccine.
A health worker is administered the Pfizer-BioNTech COVID-19 vaccine on the first day of the vaccination campaign at the Clinique for Infectious Diseases in Skopje, North Macedonia on Wednesday, Feb. 17, 2021. North Macedonia began administering vaccinations against the coronavirus Wednesday from the first batch of 4,680 doses of Pfizer vaccines donated by neighboring Serbia over the weekend.
Joana de Oliveira, 100, celebrates after getting a shot of the Oxford-AstraZeneca vaccine for COVID-19 as part of a priority vaccination program for the elderly at a vaccination center in Rio de Janeiro, Brazil, Monday, Feb. 1, 2021.
Joana de Oliveira, 100, celebrates after getting a shot of the Oxford-AstraZeneca vaccine for COVID-19 as part of a priority vaccination program for the elderly at a vaccination center in Rio de Janeiro, Brazil, Monday, Feb. 1, 2021.
Members of the over-70s arrive at the EICC to receive their first dose of coronavirus vaccination on Feb. 1, 2021, in Edinburgh, Scotland.
Members of the over-70s arrive at the EICC to receive their first dose of coronavirus vaccination on Feb. 1, 2021, in Edinburgh, Scotland.
Jamie Burnett, 28, a Garden Therapist working for Age UK, received the AstraZeneca/Oxford COVID-19 vaccination on Feb. 1, 2021, in the vaccination center at the Royal Cornwall Showground in Wadebridge, England. The National Coastguard Service has been added to the list of essential services. In total 50 large-scale vaccination centers are available across England.
Prime Minister Boris Johnson talks to Christopher Nicholls who suffered from COVID-19 at the same time as Johnson, as he visits a COVID-19 vaccination center in Batley, on Feb. 1, 2021, in West Yorkshire, England.
Prime Minister Boris Johnson talks to Christopher Nicholls who suffered from COVID-19 at the same time as Johnson, as he visits a COVID-19 vaccination center in Batley, on Feb. 1, 2021, in West Yorkshire, England.
An elderly woman gets a shot of China's Sinovac CoronaVac vaccine as part of a priority COVID-19 vaccination program for the elderly at a drive-thru vaccination center in Rio de Janeiro, Brazil, Monday, Feb. 1, 2021.
An elderly woman gets a shot of China's Sinovac CoronaVac vaccine as part of a priority COVID-19 vaccination program for the elderly at a drive-thru vaccination center in Rio de Janeiro, Brazil, Monday, Feb. 1, 2021.
Members of the over-70s arrive at the EICC to receive their first dose of coronavirus vaccination on Feb. 1, 2021, in Edinburgh, Scotland. Mass vaccination centers, including Edinburgh International Conference Centre and Aberdeen’s P&J; LIVE at TECA, opened today as the vaccination program moves to the next stage.
Members of the over-70s arrive at the EICC to receive their first dose of coronavirus vaccination on Feb. 1, 2021, in Edinburgh, Scotland. Mass vaccination centers, including Edinburgh International Conference Centre and Aberdeen’s P&J; LIVE at TECA, opened today as the vaccination program moves to the next stage.
South African law enforcement vehicles provide security for two refrigeration trucks transporting the AstraZenica vaccine that arrived earlier from India, near Johannesburg on Monday, Feb. 1, 2021. South Africa has welcomed the delivery of its first one million doses and will be administered to frontline workers in approximately two weeks.
South African law enforcement vehicles provide security for two refrigeration trucks transporting the AstraZenica vaccine that arrived earlier from India, near Johannesburg on Monday, Feb. 1, 2021. South Africa has welcomed the delivery of its first one million doses and will be administered to frontline workers in approximately two weeks.
People arrive for vaccination against the COVID-19 disease at a vaccination center at the fairgrounds in Hannover, Germany, Monday, Feb. 1, 2021. Because of the vaccine shortage, only four of eight vaccination lines are in operation at the center.
People arrive for vaccination against the COVID-19 disease at a vaccination center at the fairgrounds in Hannover, Germany, Monday, Feb. 1, 2021. Because of the vaccine shortage, only four of eight vaccination lines are in operation at the center.
An elderly woman gets a shot of China's Sinovac CoronaVac vaccine as part of a priority COVID-19 vaccination program for the elderly at a drive-thru vaccination center in Rio de Janeiro, Brazil, Monday, Feb. 1, 2021.
An elderly woman gets a shot of China's Sinovac CoronaVac vaccine as part of a priority COVID-19 vaccination program for the elderly at a drive-thru vaccination center in Rio de Janeiro, Brazil, Monday, Feb. 1, 2021.
NHS staff during the AstraZeneca/Oxford COVID-19 vaccination program on Feb. 1, 2021, in the vaccination center at the Royal Cornwall Showground in Wadebridge, England.
NHS staff during the AstraZeneca/Oxford COVID-19 vaccination program on Feb. 1, 2021, in the vaccination center at the Royal Cornwall Showground in Wadebridge, England.
Spanish nurse Irene Vazquez, 28, pauses after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine at the Nurse Isabel Zendal Hospital in Madrid, Spain, Monday, Feb. 1, 2021.
Spanish nurse Irene Vazquez, 28, pauses after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine at the Nurse Isabel Zendal Hospital in Madrid, Spain, Monday, Feb. 1, 2021.
An ultra-Orthodox Jewish man receives a Pfizer-BioNTech coronavirus vaccine at a COVID-19 vaccination center in the West Bank Jewish settlement of Givat Zeev, near Jerusalem, Monday, Feb. 1, 2021.
An ultra-Orthodox Jewish man receives a Pfizer-BioNTech coronavirus vaccine at a COVID-19 vaccination center in the West Bank Jewish settlement of Givat Zeev, near Jerusalem, Monday, Feb. 1, 2021.
In this Jan. 31, 2021, photo, registered Nurse Rita Alba gives a patient the first dose of the coronavirus vaccine at a pop-up COVID-19 vaccination site at the Bronx River Community Center in the Bronx borough of New York. The deadliest month of the coronavirus outbreak in the U.S. drew to a close with certain signs of progress. COVID-19 cases and hospitalizations are trending downward, while vaccinations are picking up speed.
Seniors wait in the recovery area after receiving the first dose of the coronavirus vaccine at a pop-up COVID-19 vaccination site at the Bronx River Community Center, Sunday, Jan. 31, 2021, in the Bronx borough of New York.
Seniors wait in the recovery area after receiving the first dose of the coronavirus vaccine at a pop-up COVID-19 vaccination site at the Bronx River Community Center, Sunday, Jan. 31, 2021, in the Bronx borough of New York.
Bolivia's President Luis Arce, center back, watches as a healthcare worker vaccinates Dr. Rafael Rodriguez with a dose of Russia's Sputnik V COVID-19 vaccine, at the Del Norte Hospital in El Alto, Bolivia, Saturday, Jan. 30, 2021.
Bolivia's President Luis Arce, center back, watches as a healthcare worker vaccinates Dr. Rafael Rodriguez with a dose of Russia's Sputnik V COVID-19 vaccine, at the Del Norte Hospital in El Alto, Bolivia, Saturday, Jan. 30, 2021.
Drivers with a vaccine appointment enter a mega COVID-19 vaccination site set up in the parking lot of Dodger Stadium in Los Angeles on Saturday, Jan. 30, 2021. One of the largest vaccination sites in the country was temporarily shut down Saturday because dozen of protesters blocked the entrance, stalling hundreds of motorists who had been waiting in line for hours, the Los Angeles Times reported. The Los Angeles Fire Department shut the entrance to the vaccination center at Dodger Stadium about 2 p.m. as a precaution, officials told the newspaper. The protesters had members of anti-vaccine and far-right groups, the Times reported. Some of them carried signs decrying the COVID-19 vaccine and shouting for people not to get the shots.
A woman receives the Sputnik-V COVID-19 vaccine at a vaccination center in Blida, south of Algiers, Algeria, Saturday, Jan. 30, 2021. The vaccines were delivered to the Boufarik military airport west of Algiers, Minister Amar Belhimeur said in a statement. He did not indicate how many arrived, though the government had said it had ordered the first batch of 500,000 Sputnik doses.
Nurse Marianne Williams administers a COVID-19 vaccine to a woman as a coworker looks on at the county health department in Tuskegee, Ala. on Monday, Jan. 25, 2021. The clinic has yet to reach its maximum capacity for immunizing people in the mostly Black city, the site of the infamous "Tuskegee syphilis study," that ended in 1972.
Nurse Marianne Williams administers a COVID-19 vaccine to a woman as a coworker looks on at the county health department in Tuskegee, Ala. on Monday, Jan. 25, 2021. The clinic has yet to reach its maximum capacity for immunizing people in the mostly Black city, the site of the infamous "Tuskegee syphilis study," that ended in 1972.
Health care workers queue before receiving a dose of the Pfizer-BioNTech COVID-19 vaccine at Gregorio Maranon Hospital during the third wave of the coronavirus pandemic on Jan. 14, 2021, in Madrid, Spain. Spain has administered more than 500 thousand doses of coronavirus vaccine to elderly residents and staff in nursing homes and health care workers. With 2.18 million cases recorded since the start of the pandemic, Spain has reported over 50,000 COVID-19 deaths.
A healthcare worker vaccinates a colleague against COVID-19 with Sinovac's Coronavac vaccine at Prof. Dr. Cemil Tascioglu City Hospital on Jan. 14, 2021, in Istanbul, Turkey. Turkey received three million doses of China's Sinovac Coronavac vaccine on December 30 and has begun the first phase of vaccinations starting with the country's more than 1.1 million medical workers.
A healthcare worker vaccinates a colleague against COVID-19 with Sinovac's Coronavac vaccine at Prof. Dr. Cemil Tascioglu City Hospital on Jan. 14, 2021, in Istanbul, Turkey.
A healthcare worker vaccinates a colleague against COVID-19 with Sinovac's Coronavac vaccine at Prof. Dr. Cemil Tascioglu City Hospital on Jan. 14, 2021, in Istanbul, Turkey.
A nurse administers a COVID-19 vaccine to an elderly person as Jordan starts the national vaccination campaign at a special vaccination clinic on Jan. 13, 2021, in Amman, Jordan. Jordan has announced it will deliver two types of vaccine, Cinopharm and Pfizer, and that the priority groups will be the elderly and health staff.
A nurse administers a COVID-19 vaccine to an elderly person as Jordan starts the national vaccination campaign at a special vaccination clinic on Jan. 13, 2021, in Amman, Jordan. Jordan has announced it will deliver two types of vaccine, Cinopharm and Pfizer, and that the priority groups will be the elderly and health staff.
People react as they leave after receiving a COVID-19 vaccine on the opening day of the Disneyland COVID-19 vaccination "super Point-of-Dispensing" (POD) site, Jan. 13, 2021, in Anaheim, Calif. California's Disneyland opened a giant coronavirus vaccination center on January 13, some 10 months after the pandemic's appearance forced the closure of the world-famous theme park. The first few hundred patients lucky enough to bag online appointments drove up to the Anaheim resort's parking lot Wednesday morning, where those over 65 and health care workers are being inoculated in white tents.
Elderly people sit in a queue to receive their free COVID-19 vaccination, as Jordan starts the national vaccination campaign at a special vaccination clinic on Jan. 13, 2021, in Amman, Jordan.
Elderly people sit in a queue to receive their free COVID-19 vaccination, as Jordan starts the national vaccination campaign at a special vaccination clinic on Jan. 13, 2021, in Amman, Jordan.
A sign for a coronavirus disease (COVID-19) vaccination center is installed in front of the red carpet of the Palace on Jan. 13, 2021, in Cannes, France.
A sign for a coronavirus disease (COVID-19) vaccination center is installed in front of the red carpet of the Palace on Jan. 13, 2021, in Cannes, France.
People wait in line to receive the COVID-19 vaccine at a mass vaccination site in a parking lot for Disneyland Resort on Jan. 13, 2021, in Anaheim, Calif.
People wait in line to receive the COVID-19 vaccine at a mass vaccination site in a parking lot for Disneyland Resort on Jan. 13, 2021, in Anaheim, Calif.
People arrive at a Disneyland parking lot to receive COVID-19 vaccines on the opening day of the Disneyland Covid-19 vaccination "super Point-of-Dispensing" (POD) site, Jan. 13, 2021, in Anaheim, Calif.
People arrive at a Disneyland parking lot to receive COVID-19 vaccines on the opening day of the Disneyland Covid-19 vaccination "super Point-of-Dispensing" (POD) site, Jan. 13, 2021, in Anaheim, Calif.
People get vaccinated against COVID-19 at the Cannes Palace of Festivals and Conferences on Jan. 13, 2021, in Cannes, France. The Cannes Palace of Festivals and Conferences, the flagship for the Cannes Film Festival, has been converted into a vaccination center.
People get vaccinated against COVID-19 at the Cannes Palace of Festivals and Conferences on Jan. 13, 2021, in Cannes, France. The Cannes Palace of Festivals and Conferences, the flagship for the Cannes Film Festival, has been converted into a vaccination center.
Health care workers receive a dose of the Pfizer-BioNTech COVID-19 vaccine at Gregorio Maranon Hospital during the third wave of the coronavirus pandemic on Jan. 14, 2021, in Madrid, Spain.
Health care workers receive a dose of the Pfizer-BioNTech COVID-19 vaccine at Gregorio Maranon Hospital during the third wave of the coronavirus pandemic on Jan. 14, 2021, in Madrid, Spain.
People wait in line to receive the COVID-19 vaccine at a mass vaccination site in a parking lot for Disneyland Resort on Jan. 13, 2021, in Anaheim, Calif.
People wait in line to receive the COVID-19 vaccine at a mass vaccination site in a parking lot for Disneyland Resort on Jan. 13, 2021, in Anaheim, Calif.
People arrive at Jackson Memorial Hospital to receive the COVID-19 vaccine, Wednesday, Jan. 6, 2021, in Miami. The push to vaccinate people over age 65 in Florida is drawing thousands of eager seniors in uneven rollouts across various counties.
People arrive at Jackson Memorial Hospital to receive the COVID-19 vaccine, Wednesday, Jan. 6, 2021, in Miami. The push to vaccinate people over age 65 in Florida is drawing thousands of eager seniors in uneven rollouts across various counties.
A healthcare worker, left, is administered a shot of the Pfizer-BioNTech coronavirus vaccine at a mass vaccination center in Veghel, Netherlands, Wednesday, Jan. 6, 2021. Nearly two weeks after most other European Union nations, the Netherlands on Wednesday began its COVID-19 vaccination program, with care home staff and frontline workers in hospitals first in line for the shot.
Doctor Dimitar Nikolakov, center, prepares to inject Doctor Georgieva, left, with the Pfizer-BioNTech COVID-19 vaccine at St. Anna Hospital on Jan. 6, 2021, in Sofia, Bulgaria. Bulgaria's vaccination campaign began on December 27 with medical workers included among the priority groups.
Doctor Dimitar Nikolakov, center, prepares to inject Doctor Georgieva, left, with the Pfizer-BioNTech COVID-19 vaccine at St. Anna Hospital on Jan. 6, 2021, in Sofia, Bulgaria. Bulgaria's vaccination campaign began on December 27 with medical workers included among the priority groups.
Dr. Christian Chidiac gets a Pfizer-BioNTech COVID-19 vaccine in La Croix-Rousse hospital, in Lyon, central France, Wednesday, Jan. 6, 2021. Amid public outcry, France's health minister promised Tuesday an "exponential" acceleration of his country's shockingly slow coronavirus vaccination process.
Dr. Christian Chidiac gets a Pfizer-BioNTech COVID-19 vaccine in La Croix-Rousse hospital, in Lyon, central France, Wednesday, Jan. 6, 2021. Amid public outcry, France's health minister promised Tuesday an "exponential" acceleration of his country's shockingly slow coronavirus vaccination process.
Stacy Wilson, an RN with the Wilson County Health Department inoculates former Gov. Jim Hunt and his wife Carolyn with their first dose of the Moderna COVID-19 vaccine at the Wilson County Health Department on Wednesday, Jan. 6, 2021, in Wilson, N.C. They will return in 28 days for the second dose of the vaccine.
Stacy Wilson, an RN with the Wilson County Health Department inoculates former Gov. Jim Hunt and his wife Carolyn with their first dose of the Moderna COVID-19 vaccine at the Wilson County Health Department on Wednesday, Jan. 6, 2021, in Wilson, N.C. They will return in 28 days for the second dose of the vaccine.
In this photo provided by The Mendocino Voice, a health care worker directs people lined up in the Adventist Health Ukiah Valley Medical Center on Monday, Jan. 4, 2021, in Ukiah, Calif. to get the Moderna COVID-19 vaccination during an emergency vaccine drive. A power failure for the freezer holding the county's ration of the Moderna vaccines forced the emergency distribution of 850 doses of that vaccine.
In this photo provided by The Mendocino Voice, people line up outside the Adventist Health Ukiah Valley Medical Center, Monday, Jan. 4, 2021, in Ukiah, Calif., to get the Moderna COVID-19 vaccination during an emergency vaccine drive. A power failure for the freezer holding the county's ration of the Moderna vaccines forced the emergency distribution of 850 doses of that vaccine.
82-year-old Brian Pinker receives the Oxford University/AstraZeneca COVID-19 vaccine from nurse Sam Foster at the Churchill Hospital in Oxford, England on Monday, Jan. 4, 2021. Pinker, a retired maintenance manager received the first injection of the new vaccine developed by Oxford University and drug giant AstraZeneca.
82-year-old Brian Pinker receives the Oxford University/AstraZeneca COVID-19 vaccine from nurse Sam Foster at the Churchill Hospital in Oxford, England on Monday, Jan. 4, 2021. Pinker, a retired maintenance manager received the first injection of the new vaccine developed by Oxford University and drug giant AstraZeneca.
Britain's Prime Minister Boris Johnson watches as junior sister Susan Cole is injected with the Oxford-AstraZeneca COVID-19 vaccine during a visit to view the vaccination program at the Chase Farm Hospital in north London on Monday, Jan. 4, 2021, part of the Royal Free London NHS Foundation Trust.
Britain's Prime Minister Boris Johnson watches as junior sister Susan Cole is injected with the Oxford-AstraZeneca COVID-19 vaccine during a visit to view the vaccination program at the Chase Farm Hospital in north London on Monday, Jan. 4, 2021, part of the Royal Free London NHS Foundation Trust.
Professor Andrew Pollard, Director of the Oxford Vaccine Group, and a professor of pediatric infection and immunity, receives the Oxford University/AstraZeneca COVID-19 vaccine from nurse Sam Foster, at the Churchill Hospital in Oxford, England on Monday, Jan. 4, 2021. England’s National Health Service says a retired maintenance manager has received the first injection of the new vaccine developed by Oxford University and drug giant AstraZeneca. Dialysis patient Brian Pinker became the very first person to be vaccinated by the chief nurse at Oxford University Hospital.
People wearing face masks wait to receive a coronavirus vaccine at a COVID-19 vaccination center in Jerusalem on Monday, Jan. 4, 2021.
People wearing face masks wait to receive a coronavirus vaccine at a COVID-19 vaccination center in Jerusalem on Monday, Jan. 4, 2021.
A nurse prepares a vaccine prior to the vaccination of elderly people at a nursing house in Athens, Greece on Monday, Jan. 4, 2021. Vaccinations were expanded from 9 to 50 hospitals nationwide on Monday.
A nurse prepares a vaccine prior to the vaccination of elderly people at a nursing house in Athens, Greece on Monday, Jan. 4, 2021. Vaccinations were expanded from 9 to 50 hospitals nationwide on Monday.
People receive coronavirus vaccines at a COVID-19 vaccination center in Ramat Gan, Israel, Sunday, Jan. 3, 2021.
People receive coronavirus vaccines at a COVID-19 vaccination center in Ramat Gan, Israel, Sunday, Jan. 3, 2021.
COVID-19 vaccines are administered to a senior in a car at Tradewinds Park in Coconut Creek, Fla. on Sunday, Jan. 3, 2021.
COVID-19 vaccines are administered to a senior in a car at Tradewinds Park in Coconut Creek, Fla. on Sunday, Jan. 3, 2021.
People who qualify under Phase 1A or Phase 1B of the state's guidelines waiting to receive the COVID-19 vaccine on Sunday, Jan. 3, 2021, at a Houston Health Department's COVID-19 vaccine clinic in Houston, Tex.
People who qualify under Phase 1A or Phase 1B of the state's guidelines waiting to receive the COVID-19 vaccine on Sunday, Jan. 3, 2021, at a Houston Health Department's COVID-19 vaccine clinic in Houston, Tex.
People who qualify under Phase 1A or Phase 1B of the state's guidelines wait for their turn to receive the COVID-19 vaccine on Sunday, Jan. 3, 2021, at a Houston Health Department's COVID-19 vaccine clinic in Houston, Tex. The department vaccinated 1,008 people who qualify under Phase 1A or Phase 1B of the state's guidelines at the clinic's first day on Saturday.
People participating in a COVID-19 vaccine delivery system trial wait for their turn at a COVID-19 vaccination center in New Delhi, India on Saturday, Jan. 2, 2021. India tested its COVID-19 vaccine delivery system with a nationwide trial on Saturday as it prepares to roll-out an inoculation program to stem the coronavirus pandemic. Saturday's exercise included necessary data entry into an online platform for monitoring vaccine delivery, along with testing of cold storage and transportation arrangements for the vaccine, the health ministry had said.
Luigi Monte receives the COVID-19 vaccine at the Don Orione home in Rome, Italy on Saturday, Jan. 2, 2021. The elderly at the Don Orione home received the COVID-19 vaccine Saturday in Rome, in a second round of vaccinations following those for health workers last week.
Luigi Monte receives the COVID-19 vaccine at the Don Orione home in Rome, Italy on Saturday, Jan. 2, 2021. The elderly at the Don Orione home received the COVID-19 vaccine Saturday in Rome, in a second round of vaccinations following those for health workers last week.
Public Health Service medical personnel applaud after Teresa Poeta, sitting at left, received the COVID-19 vaccine at the Don Orione rest home in Rome, Italy on Saturday, Jan. 2, 2021.
Public Health Service medical personnel applaud after Teresa Poeta, sitting at left, received the COVID-19 vaccine at the Don Orione rest home in Rome, Italy on Saturday, Jan. 2, 2021.
In this photo released by Xinhua News Agency, residents wait for 30 minutes at an observation point after receiving their COVID-19 vaccinations at a temporary vaccination site in Beijing, China on Saturday, Jan. 2, 2021. China authorized its first homegrown COVID-19 vaccine for general use on Dec. 31, 2020, adding another shot that could see wide use in poorer countries as the virus surges back around the globe.
Medical staff makes a toast to the new year at the vaccine center of Santo Spirito Hospital in Rome, Italy on Friday, Jan. 1, 2021. Over 32,000 doses of the COVID-19 vaccine were given to doctors and nurses in Italy to date, as the vaccine campaign goes on.
Medical staff makes a toast to the new year at the vaccine center of Santo Spirito Hospital in Rome, Italy on Friday, Jan. 1, 2021. Over 32,000 doses of the COVID-19 vaccine were given to doctors and nurses in Italy to date, as the vaccine campaign goes on.
This undated photo provided by Arvena Peshlakai shows Melvin Luke Peshlakai, left, and Arvena Peshlakai at their home in Crystal, New Mexico. The couple volunteered to participate in coronavirus vaccine trials on the Navajo Nation. As coronavirus vaccines were being developed around the world, few Native American tribes signed up to participate. The reasons range from unethical practices of the past to the quick nature of the studies amid the pandemic. Native researchers say without participation from tribal communities, tribes won't know which vaccine might best be suited for their citizens.
Myrtle Thompson receives a shot of the COVID-19 vaccine from Wayne County Health Department Administrator and Director of Nursing Tracey Sebastian, as the health department offers COVID-19 vaccines for anyone 80 years of age or older at a drive-thru site on Thursday, Dec. 31, 2020, in Wayne, W.Va.
Myrtle Thompson receives a shot of the COVID-19 vaccine from Wayne County Health Department Administrator and Director of Nursing Tracey Sebastian, as the health department offers COVID-19 vaccines for anyone 80 years of age or older at a drive-thru site on Thursday, Dec. 31, 2020, in Wayne, W.Va.
Vehicles line up as the Wayne County Health Department administers COVID-19 vaccines for anyone 80 years of age or older at a drive-thru site on Thursday, Dec. 31, 2020, in Wayne, W.Va.
Vehicles line up as the Wayne County Health Department administers COVID-19 vaccines for anyone 80 years of age or older at a drive-thru site on Thursday, Dec. 31, 2020, in Wayne, W.Va.
Patricia Marson is comforted by therapy dog Cleo as she becomes the first patient at Hebrew Rehabilitation Center to receive a COVID-19 vaccine on Wednesday, Dec. 30, 2020, in Boston, Mass. At far left is nurse Lisa Lopes and at far right is chaplain Hali Diecidue.
Patricia Marson is comforted by therapy dog Cleo as she becomes the first patient at Hebrew Rehabilitation Center to receive a COVID-19 vaccine on Wednesday, Dec. 30, 2020, in Boston, Mass. At far left is nurse Lisa Lopes and at far right is chaplain Hali Diecidue.
Former Miami Dolphins football player Nat Moore, 69, left, bumps fists with music producer Emilio Estefan, 67, right, before receiving the Pfizer-BioNTech COVID-19 vaccine at Jackson Memorial Hospital on Wednesday, Dec. 30, 2020, in Miami, Fla. Jackson Health System is starting to vaccinate people over the age of 65 this week.
Former Miami Dolphins football player Nat Moore, 69, left, bumps fists with music producer Emilio Estefan, 67, right, before receiving the Pfizer-BioNTech COVID-19 vaccine at Jackson Memorial Hospital on Wednesday, Dec. 30, 2020, in Miami, Fla. Jackson Health System is starting to vaccinate people over the age of 65 this week.
A health worker is given the Pfizer-BioNTech vaccine for COVID-19 at the N-1 military base in Mexico City, Mexico on Wednesday, Dec. 30, 2020.
A health worker is given the Pfizer-BioNTech vaccine for COVID-19 at the N-1 military base in Mexico City, Mexico on Wednesday, Dec. 30, 2020.
A medical worker, right, prepares a shot of Russia's Sputnik V coronavirus vaccine in Moscow, Russia on Wednesday, Dec. 30, 2020. Russia's Health Ministry has allowed a domestically-designed coronavirus vaccine to be given to people older than 60. Sputnik V's developers have said data suggests the vaccine was 91% effective, a conclusion based on 78 coronavirus infections among nearly 23,000 participants. That's far fewer cases than Western drugmakers have accumulated during final testing before analyzing how well their vaccine candidates worked.
Registered nurse Amanda Wright, left, gives a shot of the Moderna COVID-19 vaccine to registered nurse Paul Smith at Augusta University in Augusta, Ga. on Wednesday morning, Dec. 30, 2020.
Registered nurse Amanda Wright, left, gives a shot of the Moderna COVID-19 vaccine to registered nurse Paul Smith at Augusta University in Augusta, Ga. on Wednesday morning, Dec. 30, 2020.
Hamilton County Health Department worker Shelly Donahue gives a shot of the COVID-19 vaccine near the Hubert Fry Center at the Tennessee Riverpark on Wednesday, Dec. 30, 2020, in Chattanooga, Tenn. The Hamilton County Health Department continued distributing vaccines following the State of Tennessee's response plan at their Vaccination Drive-Thru Point of Dispensing.
In this photo provided by the Turkish Health Ministry, officials unload the first batch of COVID-19 vaccine, CoronaVac, a so-called inactivated vaccine developed by Chinese biopharmaceutical company Sinovac Biotech, at Esenboga Airport in Ankara, Turkey, early Wednesday, Dec. 30, 2020. Turkey has signed a deal for 50 million doses of the vaccine with Sinovac Biotech.
A health worker directs a vehicle before administering a COVID-19 vaccine to one of about 300 people to get vaccinated on Wednesday, Dec. 30, 2020, at the Manatee County Public Safety Center in Bradenton, Fla.
A health worker directs a vehicle before administering a COVID-19 vaccine to one of about 300 people to get vaccinated on Wednesday, Dec. 30, 2020, at the Manatee County Public Safety Center in Bradenton, Fla.
A Bedouin woman receives a Pfizer COVID-19 vaccine at a medical center in the Bedouin local council of Segev Shalom near the city of Beersheba, southern Israel, Wednesday, Dec. 30, 2020.
A Bedouin woman receives a Pfizer COVID-19 vaccine at a medical center in the Bedouin local council of Segev Shalom near the city of Beersheba, southern Israel, Wednesday, Dec. 30, 2020.
An FDNY Registered Nurse (RN) administers a dose of the Moderna COVID-19 vaccine to an FDNY Certified First Responder (CFR) Firefighter at the Fire Department Headquarters in Brooklyn on Tuesday, Dec. 29, 2020. The Department can vaccinate up to 450 members per day at the three locations combined. Vaccinations are not mandatory but are strongly encouraged. Since the start of the pandemic, the Department has lost 12 members to COVID-19, including five members of EMS and seven civilians.
An FDNY Registered Nurse (RN) administer a dose of the Moderna COVID-19 vaccine to Martha Erekke a FDNY Certified First Responder (CFR) Firefighter at the Fire Department Headquarters in Brooklyn on Tuesday, Dec. 29, 2020.
An FDNY Registered Nurse (RN) administer a dose of the Moderna COVID-19 vaccine to Martha Erekke a FDNY Certified First Responder (CFR) Firefighter at the Fire Department Headquarters in Brooklyn on Tuesday, Dec. 29, 2020.
In this photo provided by United States Forces Korea, Gen. Robert B. Abrams, Commanding General for United States Forces Korea, receives the COVID-19 vaccine at Brian D. Allgood Army Community Hospital, U.S. Army Garrison Humphreys, in Pyeongtaek, South Korea on Tuesday, Dec. 29, 2020. The United States has started vaccinating its troops based in South Korea, as its Asian ally reported its highest daily COVID-19 fatalities amid surging cases in the country.
A health worker is vaccinated against the coronavirus in Pamplona, northern Spain, Tuesday, Dec. 29. 2020. Spain plans to receive over 4.5 million doses of the vaccine over the next three months, enough it says to immunize just over 2.2 million people. The government estimates that this first phase will be enough to cover nursing home residents and workers, followed by health workers in general and people with disabilities.
Employees of the international courier company DHL unload a shipping container with vaccines against COVID-19 at Athens' International airport in Sparta, east of Athens on Tuesday, Dec. 29, 2020.  Greece received the second batch of 83,850 doses of the Pfizer-BioNTech vaccines against COVID-19 on Tuesday.
Employees of the international courier company DHL unload a shipping container with vaccines against COVID-19 at Athens' International airport in Sparta, east of Athens on Tuesday, Dec. 29, 2020. Greece received the second batch of 83,850 doses of the Pfizer-BioNTech vaccines against COVID-19 on Tuesday.
Kathleen Sawtelle, a pharmacist with Health Direct, gives the Pfizer's COVID-19 vaccine to Rebecca McKenny, a resident of Thompson House Rehabilitation & Nursing Center, in Brattleboro, Vt. on Tuesday, Dec. 29, 2020.
Kathleen Sawtelle, a pharmacist with Health Direct, gives the Pfizer's COVID-19 vaccine to Rebecca McKenny, a resident of Thompson House Rehabilitation & Nursing Center, in Brattleboro, Vt. on Tuesday, Dec. 29, 2020.
Pat Moore, with the Chester County, Pa., Health Department, fills a syringe with Moderna COVID-19 vaccine before administering it to emergency medical workers and healthcare personnel at the Chester County Government Services Center, Tuesday, Dec. 29, 2020, in West Chester, Pa.
Pat Moore, with the Chester County, Pa., Health Department, fills a syringe with Moderna COVID-19 vaccine before administering it to emergency medical workers and healthcare personnel at the Chester County Government Services Center, Tuesday, Dec. 29, 2020, in West Chester, Pa.
Vice President-Elect Kamala Harris receives the Moderna COVID-19 vaccine from nurse Patricia Cummings on Tuesday, Dec. 29, 2020, at United Medical Center in southeast Washington, DC.
Vice President-Elect Kamala Harris receives the Moderna COVID-19 vaccine from nurse Patricia Cummings on Tuesday, Dec. 29, 2020, at United Medical Center in southeast Washington, DC.
Nurse Gustavo Rodriguez gives nurse Florencia Arroyo a shot of Russia's Sputnik V vaccine for COVID-19 at Dr. Pedro Fiorito Hospital in Avellaneda, Argentina on Tuesday, Dec. 29, 2020.
Nurse Gustavo Rodriguez gives nurse Florencia Arroyo a shot of Russia's Sputnik V vaccine for COVID-19 at Dr. Pedro Fiorito Hospital in Avellaneda, Argentina on Tuesday, Dec. 29, 2020.
Tayebeh Mokhber is injected with the Coviran coronavirus vaccine produced by Shifa Pharmed, part of a state-owned pharmaceutical conglomerate, in a ceremony in Tehran, Iran on Tuesday, Dec. 29, 2020. The first study of the safety and effectiveness of the coronavirus vaccine in Iran began Tuesday, state TV reported, with dozens due to receive the domestically-developed shot in the hardest-hit country in the Middle East.
A health staff worker holds some Pfizer coronavirus vaccines before vaccinating health workers in Pamplona, northern Spain, Tuesday, Dec. 29. 2020.
A health staff worker holds some Pfizer coronavirus vaccines before vaccinating health workers in Pamplona, northern Spain, Tuesday, Dec. 29. 2020.
A nurse administers a COVID-19 vaccine to Josepha Delmotte, 102 years old, at La Bonne Maison de Bouzanton care home in Mons, Belgium on Monday, Dec. 28, 2020. The vaccine, developed by BioNTech and Pfizer, was transported from a hospital in Leuven to the residential care home on Monday, as Belgium begins its vaccination program starting with the most vulnerable.
Los Angeles Fire Department Capt. Elliot Ibanez, left, receives the Moderna COVID-19 vaccine given by LAFD paramedic Anthony Kong at Station 4 on Monday, Dec. 28, 2020, in Los Angeles, Calif.
Los Angeles Fire Department Capt. Elliot Ibanez, left, receives the Moderna COVID-19 vaccine given by LAFD paramedic Anthony Kong at Station 4 on Monday, Dec. 28, 2020, in Los Angeles, Calif.
In this Dec. 23, 2020 file photo, New York City firefighter emergency medical services personnel are vaccinated against COVID-19 at the FDNY Fire Academy in New York. An ambitious goal of vaccinating 1 million New York City residents against COVID-19 in January was set Thursday by Mayor Bill de Blasio, who noted that meeting the target would require outside cooperation and the city dramatically increasing access.
In this Dec. 21, 2020 file photo, Kelley Dixon, 78, is vaccinated against COVID-19 at his residence in The Hebrew Home in Riverdale. An ambitious goal of vaccinating 1 million New York City residents against COVID-19 in January was set Thursday by Mayor Bill de Blasio, who noted that meeting the target would require outside cooperation and the city dramatically increasing access.
Maria Teresa Gooch, an employee at The Hebrew Home in Riverdale is vaccinated against COVID-19 at the nursing home in New York on Monday, Dec. 21, 2020. The nursing home is starting with 600 doses of the vaccine and is hoping to have all of its residents and staff vaccinated over the next few weeks.
Maria Teresa Gooch, an employee at The Hebrew Home in Riverdale is vaccinated against COVID-19 at the nursing home in New York on Monday, Dec. 21, 2020. The nursing home is starting with 600 doses of the vaccine and is hoping to have all of its residents and staff vaccinated over the next few weeks.
President-elect Joe Biden holds his wife Jill Biden's hand after receiving his first dose of the coronavirus vaccine from Tabe Mase at Christiana Hospital on live television in Newark, Del. on Monday, Dec. 21, 2020.
President-elect Joe Biden holds his wife Jill Biden's hand after receiving his first dose of the coronavirus vaccine from Tabe Mase at Christiana Hospital on live television in Newark, Del. on Monday, Dec. 21, 2020.

“However, we are encouraged by the increasing wealth of evidence from independent studies and real world data which reinforces the effectiveness of the Pfizer/BioNTech vaccine in real world settings,” a Pfizer spokeswoman said in an email.

The new study, which has not been peer-reviewed, was partly funded by the National Institute for Health Research, a government agency in the U.K.

Dr. Gayatri Amirthalingam, consultant epidemiologist at Public Health England, said the findings provide further evidence of the benefits of the U.K. approach to prioritize the first dose of Pfizer’s vaccine.

“It is vital that you take up the offer of vaccination as it is the best way to protect yourself and your community and to help us out of the pandemic,” she said in a statement.

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