{"id":298026,"date":"2021-07-13T21:19:06","date_gmt":"2021-07-13T18:19:06","guid":{"rendered":"https:\/\/en.buradabiliyorum.com\/will-canadians-need-covid-booster-shots\/"},"modified":"2021-07-13T21:19:06","modified_gmt":"2021-07-13T18:19:06","slug":"will-canadians-need-covid-booster-shots","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/will-canadians-need-covid-booster-shots\/","title":{"rendered":"#Will Canadians need COVID booster shots?"},"content":{"rendered":"

“#Will Canadians need COVID booster shots?<\/strong>”<\/p>\n

\n Vaxx Populi: Data shows good immunity nine months after receiving two doses, PHAC says, though need for boosters is being ‘closely monitored’ in light of emergence of variants of concern\n <\/div>\n
\n On July 8, Pfizer and its COVID-19 vaccine partner BioNTech <\/span>announced<\/span><\/a>\u00a0that it would app<\/a>ly in coming weeks for emergency use authorization from the U.S. government for a booster to its two-dose vaccine. \u201cPfizer and BioNTech believe a third dose of BNT162b2 [its vaccine] has the potential to preserve the highest levels of protective efficacy against all currently tested variants including Delta,\u201d the press release stated. \u201cWhile protection against severe disease remained high across the full six months, a decline in efficacy against symptomatic disease over time and the continued emergence of variants are expected. Based on the totality of the data they have to date, Pfizer and BioNTech believe that a third dose may be beneficial to maintain <\/span>highest levels of protection.\u201d\u00a0<\/span><\/p>\n

U.S. government agencies and <\/span>experts <\/span><\/a>did not react favourably <\/span>to the announcement, <\/span>which occurred before <\/span>Pfizer and BioNTech published data supporting a third dose or submitted it to be peer-reviewed. \u201cAmericans who have been fully vaccinated do not need a booster shot at this time,\u201d said the U.S. Centers for Disease Control and the Food and Drug Administration in a\u00a0<\/span>joint statement<\/span><\/a>. \u201cFDA, CDC, and NIH [National Institutes of Health] are engaged in a science<\/a>-based, rigorous process to consider whether or when a booster might be necessary. This process takes into account laboratory data, clinical trial data, and cohort data\u2014which can include data from specific pharmaceutical companies, but does not rely on those data exclusively. We continue to review any new data as it becomes available and will keep the public informed. We are prepared for booster doses if and when the science demonstrates that they are needed.\u201d<\/span><\/p>\n

The Canadian government is also<\/strong> preparing for that potential eventuality. On April 23, Prime Minister Justin Trudeau announced that the federal government had \u201creached an agreement with Pfizer for 35 million booster doses for next year and 30 million in the year after. This deal includes options to add 30 million doses in both 2022 and 2023 and an option for 60 million doses in 2024.\u201d He said that Ottawa was \u201cin ongoing discussions with other vaccine manufacturers about their plans for booster shots, too.\u201d<\/span><\/p>\n

RELATED:\u00a0Vaccines extremely effective against COVID variants of concern: Canadian study<\/strong><\/p>\n<\/blockquote>\n

While Pfizer and BioNtech have announced that they will apply for authorization for a booster in both the United States and the European Union, they haven\u2019t approached Canada yet. \u201cEmerging data to date shows good immunity in most people out<\/span>\u00a0<\/b>to nine months after receiving two vaccine doses,\u201d said <\/span>the Public Health Agency of Canada, in a statement to Reuters<\/span><\/a>. \u201cIt is possible that Canadians will need a subsequent vaccination, or booster shot, after we have reached sufficient levels of community protection with the current rollout\u2026 Given the emergence of variants of concern, the need for future booster doses is being closely monitored.\u201d\u00a0<\/span><\/p>\n

In the Pfizer-BioNTech press release, the firms referenced the threat posed by the Delta variant of concern. Some <\/span>Israeli government officials <\/span><\/a>have put Pfizer\u2019s current effectiveness at 64 per cent against Delta. \u201cVaccine efficacy in preventing both infection and symptomatic disease has declined six months post-vaccination, although efficacy in preventing serious illnesses remains high,\u201d <\/span>said the Pfizer-BioNTech press release<\/span> in reference to data from Israel. While everyone awaits full analysis from Israel, experts point out that other recent studies, <\/span>including a large one from Canada<\/span>, have shown all the vaccines to be effective against Delta and the other variants.\u00a0<\/span><\/p>\n

There is no definitive study as to how long the COVID-19 vaccines remain effective, in part because they are so new. In late June, a preview of a small study<\/span> published in <\/span>Nature<\/span><\/i><\/a> suggested that mRNA vaccines, such as Pfizer and Moderna, may actually protect against the SARS-CoV-2 virus for years. \u201cIt\u2019s a good sign for how durable our immunity is from this vaccine,\u201d said Ali Ellebedy of Washington University in Missouri to the <\/span>New York Times<\/span><\/i><\/a>.<\/span><\/p>\n

RELATED:\u00a0COVID-19 in Canada: How our battle to stop the pandemic is going<\/strong><\/p>\n<\/blockquote>\n

At the same time, researchers say that boosters may be necessary for specific groups, in particular those with <\/span>weakened immune systems<\/span><\/a>\u2014such as transplant patients. Indeed, France and Israel <\/span>have already started<\/span><\/a> giving third shots to those groups. \u201cSome immunocompromised people don\u2019t mount the same immune response and may still be vulnerable to disease,\u201d tweeted Dr. Isaac Bogoch, an infectious diseases physician at the University of Toronto. That follows the pattern that occurred with second doses: Canadian provinces<\/span> shortened the interval <\/span><\/a>between first and second doses of vaccine for dialysis patients, certain cancer patients and those on immunosuppressive medications because their immune response after one dose wasn\u2019t strong enough.\u00a0<\/span><\/p>\n

In some cases, boosters are given to buttress the effectiveness of vaccines that haven\u2019t performed as well. Not all vaccines in use around the world are proving to be as effective as the mRNA ones. After both Thai and Indonesian researchers <\/span>reported breakthrough <\/span><\/a>infections among health workers who were given two doses of Sinovac, a Chinese COVID-19 vaccine, Thailand <\/span>announced<\/span><\/a> that it will offer mRNA third shots to medical staff who got Sinovac.\u00a0<\/span><\/p>\n

On June 30, Britain\u2019s Joint Committee on Vaccination and Immunisation (JCVI) produced what it called <\/span>interim advice <\/span><\/a>stating that it may roll out a booster program as soon as September, starting with those most at risk. Still it cautions that plans may \u201cbe subject to substantial change before being finalized, depending on additional scientific data expected in coming months including \u201cclinical trial and real-world effectiveness data on the durability of protection beyond six months\u201d and \u201cclinical trial data on immune responses following a third vaccination.\u201d\u00a0<\/span><\/p>\n

Pfizer\u2019s announcement comes as many nations are pleading for doses amid their own huge waves of new cases of COVID-19. Dr.\u00a0 Samir Gupta, a respirologist at St. Michael\u2019s Hospital in Toronto, tweeted<\/a><\/span>: \u201cI get it\u2014governments need to protect their own people if they want to get re-elected. But when rich countries are giving third doses just in case, while the vast majority of people in low\/middle income countries can\u2019t access a first dose, it\u2019s time for a hard look in the mirror.\u201d<\/span><\/p>\n

As Canada rolls out the country\u2019s most complex vaccination project to date, <\/i>Maclean\u2019s presents <\/i>Vaxx Populi, an ongoing series<\/a> in which Patricia Treble tackles the most pressing questions related to the new COVID-19 vaccines. Send us a question you\u2019d like answered at vaccines@macleans.ca. If you have specific questions about your own health, we recommend consulting a family doctor or the local public health authority in your area.<\/i>
\n<\/span><\/p><\/div>\n