The National Advisory Committee on Immunization (NACI; french: Comité consultatif national de l'immunisation; french: CCNI, label=none) is an advisory body that provides the

Government of Canada The government of Canada (french: gouvernement du Canada) is the body responsible for the federal administration of Canada. A constitutional monarchy, the Crown is the corporation sole, assuming distinct roles: the executive, as the ''Crown ...

with medical and scientific advice relating to human

immunization Immunization, or immunisation, is the process by which an individual's immune system becomes fortified against an infectious agent (known as the immunogen). When this system is exposed to molecules that are foreign to the body, called ''non-sel ...

History

The NACI's precursor, The National Advisory Committee on Immunizing Agents, was established in 1964. And it was mandated to provide advice on immunizing agents to the Department of National Health and Welfare. In 1975, focus on advice related to the introduction of new vaccines and to assist in the development of immunization programs became the new mandate of the committee. In 1978, the committee was officially renamed into The National Advisory Committee on Immunization, in order to reflect the new mandate for consideration of procedures related to immunization and immunization coverage.

Role

NACI is mandated to provide the

Public Health Agency of Canada The Public Health Agency of Canada (PHAC; french: Agence de la santé publique du Canada, ASPC) is an agency of the Government of Canada that is responsible for public health, emergency preparedness and response, and infectious and chronic dis ...

(PHAC) with medical, scientific, and public health advice relating to vaccines, including the use of vaccines in humans, vaccine evaluation, and the monitoring of vaccine-associated adverse events.

Membership

The NACI is composed of 14 voting members (chair, vice-chair, and 12 voting members), executive secretary, roughly a dozen industry liaison representatives, and roughly a dozen ex-officio professional

public service A public service is any service intended to address specific needs pertaining to the aggregate members of a community. Public services are available to people within a government jurisdiction as provided directly through public sector agencies ...

representatives from Health Canada. NACI's voting members composed of experts in the fields of immunization, public health, vaccine preventable diseases, pediatric or adult infectious diseases, allergy/immunology, other health related fields. As of 2022, the membership of NACI consists of:

COVID-19 pandemic

NACI became prominent during the

COVID-19 pandemic The COVID-19 pandemic, also known as the coronavirus pandemic, is an ongoing global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The novel virus was first identif ...

, as publisher of recommendations and guidance surrounding distribution of

COVID-19 vaccine A COVID19 vaccine is a vaccine intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), the virus that causes coronavirus disease 2019 ( COVID19). Prior to the COVID19 pandemic, an e ...

s. Some of NACI's recommendations have been criticized as counter-productive in terms of public health and communications concerning the pandemic.

Dose scheduling

In March 2021, amid supply shortages, NACI issued a strong recommendation that second doses of two-dose COVID-19 vaccines (such as the

AstraZeneca AstraZeneca plc () is a British-Swedish multinational pharmaceutical and biotechnology company with its headquarters at the Cambridge Biomedical Campus in Cambridge, England. It has a portfolio of products for major diseases in areas includin ...

Moderna Moderna, Inc. ( ) is an American pharmaceutical and biotechnology company based in Cambridge, Massachusetts that focuses on RNA therapeutics, primarily mRNA vaccines. These vaccines use a copy of a molecule called messenger RNA (mRNA) to pro ...

, and

Pfizer Pfizer Inc. ( ) is an American multinational pharmaceutical and biotechnology corporation headquartered on 42nd Street in Manhattan, New York City. The company was established in 1849 in New York by two German entrepreneurs, Charles Pfizer ...

vaccines) be given up to four months after the first, as opposed to the three-to-four week intervals used in the clinical trials and recommended by Health Canada. NACI stated that this recommendation was based on modelling from data showing that "the first two months of real world effectiveness are showing sustained high levels of protection."

Pfizer Canada Pfizer Inc. ( ) is an American Multinational corporation, multinational Pharmaceutical industry, pharmaceutical and biotechnology corporation headquartered on 42nd Street (Manhattan), 42nd Street in Manhattan, Manhattan, New York City. The co ...

president Cole Pinnow warned against the recommendation in the

House of Commons The House of Commons is the name for the elected lower house of the bicameral parliaments of the United Kingdom and Canada. In both of these countries, the Commons holds much more legislative power than the nominally upper house of parliament. ...

, stating that "the data that we’ve seen from a real world evidence perspective that has been used to make arguments to extend the dose schedule has been done on much younger populations", and that "we don't have any data after two months to know what the impact of one dose will be." On May 28, citing improved vaccine availability, NACI recommended that second doses be administered "as soon as possible", and especially to individuals who are at high risk, but that it "continues to recommend that jurisdictions should maximize the number of individuals benefiting from the first dose of a COVID-19 vaccine by extending the second dose of COVID-19 vaccine up to four months after the first."

mRNA vaccine preference

On May 4, 2021, NACI issued a recommendation that

mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is ...

-based vaccines should be preferred over

viral vector vaccine A viral vector vaccine is a vaccine that uses a viral vector to deliver genetic material ( DNA), which can be transcribed by the recipient's host cells as mRNA coding for a desired protein (or: antigen) to elicit an immune response. , six viral v ...

s such as the AstraZeneca and Janssen vaccines, due to the rare risk of

vaccine-induced immune thrombotic thrombocytopenia Post-vaccination embolic and thrombotic events, termed vaccine-induced immune thrombotic thrombocytopenia (VITT), vaccine-induced prothrombotic immune thrombocytopenia (VIPIT), thrombosis with thrombocytopenia syndrome (TTS), vaccine-induced imm ...

(VITT). Vice-chairman Shelley Deeks stated that "individuals need to have an informed choice to be vaccinated with the first vaccine that's available, or to wait for an mRNA vaccine." Various politicians and public health authorities argued that such statements concerning officially-approved vaccines would encourage hesitancy, and impede the public health goal of inoculating the public as quickly as possible. On May 6, NACI issued a follow-up statement wishing to clarify that their previous statement was not to imply that anyone taking a vaccine such as AstraZeneca was making a mistake, and that it was adequately effective for protecting against

COVID-19 Coronavirus disease 2019 (COVID-19) is a contagious disease caused by a virus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was COVID-19 pandemic in Hubei, identified in Wuhan, China, in December ...

Dose mixing

On 1 June 2021, NACI issued a recommendation that those who had received the AstraZeneca vaccine as their first dose may safely receive an mRNA vaccine as their second dose instead. The recommendation cited studies occurring in Europe over similar mixing of doses being performed due to concerns over the AstraZeneca vaccine, including one that showed a sevenfold increase in antibody presence in patients who received AstraZeneca as their first dose and Pfizer as their second. It is still recommended that those who received an mRNA vaccine as a first dose receive the same vaccine for their second dose, but that the two mRNA vaccines can be interchangeable if supply is limited. Public health officials warned that Canada's use and orders of the AstraZeneca had to be controlled in order to prevent waste, especially as those concerned over VITT (which was associated more with the first dose) request an mRNA option for their second dose instead. Some countries and non-Canadian businesses have refused to recognize individuals that have received mixed doses as being fully vaccinated; at U.S.-based ports, multiple cruise lines stated that they would only accept passengers fully vaccinated in means approved by the

US FDA The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food s ...

(only accepting matching does of the Moderna or Pfizer vaccine, or the Janssen vaccine). In mid-July, Prime Minister

Justin Trudeau Justin Pierre James Trudeau ( , ; born December 25, 1971) is a Canadian politician who is the 23rd and current prime minister of Canada. He has served as the prime minister of Canada since 2015 and as the leader of the Liberal Party since 2 ...

stated that they were "going to work with the international community to make sure that people who are fully vaccinated in ways that Canadians recognize as safe and effective are also recognized around the world."

References

External links

National Advisory Committee on Immunization (NACI): Statements and publications
{{Authority control 1964 establishments in Canada Canadian health officials Canadian public health doctors Government agencies established in 1964 Health Canada Organizations associated with the COVID-19 pandemic Public health organizations