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

The public is being asked to use caution when doing backyard burning in the Cariboo Fire Centre. (File photo)
Caution urged with outdoor burning says Cariboo Fire Centre

Anyone conducting burning must ensure adequate resources are on hand to stop fire from spreading

Janda Group Holdings Inc. has finalized its design for its residential unit project on the second floor of the Boitanio Mall in Williams Lake. (Janda Group Holdings Inc. image)
Boitanio Mall housing development revised design accepted by Williams Lake city council

Janda Group Holdings Inc. is planning for 82 residential units at the site

FILE — In this March 31, 2021 file photo, a nurse fills a syringe with a dose of the Johnson & Johnson’s one-dose COVID-19 vaccine at the Vaxmobile, at the Uniondale Hempstead Senior Center, in Uniondale, N.Y. The U.S. is recommending a “pause” in administration of the single-dose Johnson & Johnson COVID-19 vaccine to investigate reports of potentially dangerous blood clots. In a joint statement Tuesday, the Centers for Disease Control and Prevention and the Food and Drug Administration said it was investigating clots in six women in the days after vaccination, in combination with reduced platelet counts. (AP Photo/Mary Altaffer, File)
72 new COVID-19 cases in Interior Health

This brings the total number of cases in the region to 9,666 since the pandemic began

Photo collage of loved ones lost to substance use and overdose. (Photo courtesy Moms Stop The Harm)
B.C. overdose deaths still rising 5 years after public health emergency declared

Moms Stop the Harm calls on B.C. to provide safe supply in response to deadly illicit drug use

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

(Government of Canada)
Liberal MP caught stark naked during House of Commons video conference

William Amos, in Quebec, appeared on the screens of his fellow members of Parliament completely naked

Provincial health officer Dr. Bonnie Henry updates B.C.’s COVID-19 situation at the B.C. legislature, Feb. 1, 2020. (B.C. government)
B.C.’s COVID-19 case count jumps to 1,168 Wednesday, nearly 400 in hospital

Now 120 coronavirus patients in intensive care, six more deaths

Moss covered branches are seen in the Avatar Old Growth Forest near Port Renfrew on Vancouver Island, B.C. Thursday, Sept. 29, 2011. THE CANADIAN PRESS/Jonathan Hayward
B.C. blockades aimed at protecting old-growth forests reveal First Nation split

Two Pacheedaht chiefs say they’re ‘concerned about the increasing polarization over forestry activities’ in the territory

Richmond RCMP Chief Superintendent Will Ng said, in March, the force received a stand-out number of seven reports of incidents that appeared to have “racial undertones.” (Phil McLachlan/Capital News)
‘Racially motivated’ incidents on the rise in B.C’s 4th largest city: police

Three incidents in Richmond are currently being invested as hate crimes, says RCMP Chief Superintendent Will Ng

Commercial trucks head south towards the Pacific Highway border crossing Wednesday (April 14, 2021). The union representing Canadian border officers wants its members to be included on the frontline priority list for the COVID-19 vaccine. (Aaron Hinks photo)
CBSA officers’ union calls for vaccine priority in B.C.

Border officers at ports including, YVR and land crossings should ‘not be left behind’

A still from the video taken of a violent arrest on May 30, 2020 in downtown Kelowna. (File)
Kelowna Mountie charged with assault for caught-on-camera violent arrest

Const. Siggy Pietrzak was filmed punching a suspected impaired driver at least 10 times during an arrest

Photo collage of loved ones lost to substance use and overdose. (Photo courtesy Moms Stop The Harm)
B.C. and Victoria’s overdose deaths still rising five years after public health emergency declared

Moms Stop the Harm calls on B.C. to provide safe supply in response to deadly illicit drug use

Most Read