Studies suggest people who have been infected with the novel coronavirus may produce 10 to 45 times the antibodies after the first dose of the Pfizer-BioNTech or Moderna vaccines, compared with those who haven’t had COVID-19. The research is yet to be peer-reviewed. (AP Photo/Esteban Felix)

Studies suggest people who have been infected with the novel coronavirus may produce 10 to 45 times the antibodies after the first dose of the Pfizer-BioNTech or Moderna vaccines, compared with those who haven’t had COVID-19. The research is yet to be peer-reviewed. (AP Photo/Esteban Felix)

People infected with COVID-19 may need just one dose of vaccine, studies say

People who have had COVID-19 appear to produce 10 to 45 more times the antibodies after 1st vaccine dose

Scientists at the National Advisory Committee on Immunization are reviewing research that suggests people who have been infected with COVID-19 can turbocharge their antibodies with just one dose of a vaccine.

The committee is “actively reviewing evidence on the protection offered by one dose for those previously infected, and whether a second dose continues to be necessary,” says a statement from the panel.

Caroline Quach-Thanh said the committee is “debating” the question of how many vaccine doses someone who has been infected with COVID-19 requires.

“France and Quebec have said only one,” said Quach-Thanh, chair of the committee, in an email.

Studies have suggested people who have had COVID-19 may produce the required antibody response with just one dose of a vaccine.

A letter in the New England Journal of Medicine earlier this month says the question of whether one dose is enough “requires investigation.” It’s written by 32 researchers from the Icahn School of Medicine at Mount Sinai in New York after conducting a small study.

It suggests people who have been infected with the novel coronavirus may produce 10 to 45 times as many antibodies after the first dose of the Pfizer-BioNTech or Moderna vaccines compared with someone who hasn’t had COVID-19. The research is yet to be peer-reviewed.

Quach-Thanh said data shows that the response to the first dose of vaccine is strong for those who have been infected with the virus.

“Like a booster dose,” she said.

Those who have been infected and get a second shot may also have stronger side-effects, such as fever, aches and feeling tired, which are signs their immune system is already primed, Quach-Thanh said.

“The question that remains is: is that true for everyone or at least for the vast majority?”

Dr. Bonnie Henry, British Columbia’s provincial health officer, said early data from around the world suggest people who have had a lab-confirmed positive test for COVID-19 get a good response from just one dose of a vaccine.

“The jury is still out but more and more it is looking like they get a really strong booster effect from a single dose and a second booster may not be necessary,” she said.

Quebec’s public health director, Horacio Arruda, told a news conference earlier this week that immunization experts believe a single dose of vaccine, when given three months after recovery from the disease, provides the same amount of immunity as two doses.

A second dose, Arruda explained, is not recommended for people who have had COVID-19 because “it doesn’t give more immunity, and it brings more significant adverse effects,” such as flu-like symptoms.

Prof. Fiona Brinkman of Simon Fraser University’s molecular biology and biochemistry department said the number of antibodies produced by a person may depend on how severe their COVID-19 infection was.

That does not mean people need to get an antibody test done before getting a vaccine, although that may change, she added.

“Right now, the policy is that we’re just vaccinating everybody and doing that first dose.”

However, Quach-Thanh warned that the presence of antibodies is not, in itself, a sign of protection and they are all not created equal.

“Some people without much antibodies will have protection, while others with antibodies may not be that well protected,” she said.

Brinkman said it’s also possible that there may be a difference in the kind of antibodies produced after a COVID-19 infection and a vaccine.

“The most important thing is to have these certain antibodies — what we call neutralizing antibodies — that we really want,” she said, adding the vaccines have been shown to produce them.

The experts said there is no harm in those who have been infected with COVID-19 getting both shots.

The statement from the committee said it is also evaluating how long someone previously infected with COVID-19 could wait before getting a vaccine, based on emerging evidence.

Brinkman said one of the concerns researchers have is how long immunity might last.

“This disease literally hasn’t been around long enough to allow us to appropriately assess how long you have antibodies and an immune response that will be effective against this virus, if you’ve either been vaccinated or you’ve had the disease.”

Researchers said it could also potentially mean that the vaccine can be delivered into arms faster because a number of people may only need one dose of the shot.

“It really is good news,” Brinkman said. “If anything, it’s a good thing.”

Coronavirusvaccines

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

Just Posted

Sports broadcaster and 30-year high school football coach Farhan Lalji. (Image via farhanlalji.com)
Farhan Lalji chats about the new B.C. high school sports governance proposal

Lalji, a 30-year high school football coach, thinks the new proposal will be bad for student athletes

Delta character - and former White Rock resident - Pansy May Stuttard inspects a loaded revolver in the cover photo for Jim Dwight and Gary Cullen’s fascinating biography, Lord don’t want me Devil won’t take me. Contributed photo
West Coast’s ‘Pistol-packin’ Pansy’ lives on in colourful biography

Infamous Delta character ended her days in White Rock and South Surrey

Surrey city Councillor Brenda Locke. (File photo)
Surrey councillor trying to get policing referendum on the table, again

‘I’m sending it back for clarification,’ mayor decides

(Photo: MOSAIC/Facebook)
Organization receives $10K from B.C. government to tackle racism in Surrey, White Rock

Funding to go toward forum for International Day for the Elimination of Racial Discrimination

Vancouver resident Beryl Pye was witness to a “concerning,” spontaneous dance party that spread throughout social groups at Kitsilano Beach on April 16. (Screen grab/Beryl Pye)
VIDEO: Dance party erupts at Vancouver’s Kitsilano Beach to the dismay of onlookers

‘It was a complete disregard for current COVID-19 public health orders,’ says Vancouver resident Beryl Pye

Pall Bearers carrying the coffin of the Duke of Edinburgh, followed by the Prince of Wales, left and Princess Anne, right, into St George’s Chapel for his funeral, at Windsor Castle, in Windsor, England, Saturday April 17, 2021. (Danny Lawson/Pool via AP)
Trudeau announces $200K donation to Duke of Edinburgh award as Prince Philip laid to rest

A tribute to the late prince’s ‘remarkable life and his selfless service,’ the Prime Minister said Saturday

B.C. homeowners are being urged to take steps to prepare for the possibility of a flood by moving equipment and other assets to higher ground. (J.R. Rardon)
‘Entire province faces risk’: B.C. citizens urged to prepare for above-average spring flooding

Larger-than-normal melting snowpack poses a threat to the province as warmer weather touches down

Vancouver-based Doubleview Gold Corp. is developing claims in an area north of Telegraph Creek that occupies an important place in Tahltan oral histories, said Chad Norman Day, president of the Tahltan Central Government. (THE CANADIAN PRESS/HO)
B.C. Indigenous nation opposes mineral exploration in culturally sensitive area

There’s “no way” the Tahltan would ever support a mine there, says Chad Norman Day, president of its central government

Stz’uminus Elder George Harris, Ladysmith Mayor Aaron Stone, and Stz’uminus Chief Roxanne Harris opened the ceremony. (Cole Schisler photo)
Symbolic red dresses rehung along B.C. highway after vandals tore them down

Leaders from Stz’uminus First Nation and the Town of Ladysmith hung new dresses on Sat. April 17

A Western toadlet crosses the centre line of Elk View Road in Chilliwack on Aug. 26, 2010. A tunnel underneath the road has since been installed to help them migrate cross the road. Saturday, April 24 is Save the Frogs Day. (Jenna Hauck/ Progress File)
Unofficial holidays: Here’s what people are celebrating for the week of April 18 to 24

Save the Frogs Day, Love Your Thighs Day and Scream Day are all coming up this week

Local carpenter Tyler Bohn embarked on a quest to create the East Sooke Treehouse, after seeing people build similar structures on a Discovery Channel show. (East Sooke Treehouse Facebook photo)
PHOTOS: B.C. carpenter builds fort inspired by TV’s ‘Treehouse Masters’

The whimsical structure features a wooden walking path, a loft, kitchen – and is now listed on Airbnb

The Attorney General’s Ministry says certain disputes may now be resolved through either a tribunal or the court system, pending its appeal of a B.C. Supreme Court decision that reduced the tribunal’s jurisdiction. (AP Photo/Mark J. Terrill)
Court of Appeal grants partial stay in ruling on B.C. auto injuries

B.C. trial lawyers challenged legislation brought in to cap minor injury awards and move smaller court disputes to the Civil Resolution Tribunal

An Extinction Rebellion Vancouver Island (XRVI) climate change event in 2019 saw a large crowd occupy the Johnson Street bridge. Black Press File Photo
‘In grief for our dying world’: B.C. climate activists embark on 4-day protest

Demonstrators will walk through Vancouver for the first two days before boarding a ferry Sunday morning

Most Read