Ontario Immunization Advisory Committee recommended that if an 11 and 12-year-old child is inadvertently given a second dose of the Pfizer-BioNTech vaccine that is not authorized for their age, the dose should be considered valid and the series complete.
National Advisory Committee on Immunization (NACI) recommends that a booster dose of an authorized mRNA COVID-19 vaccine should be offered to vulnerable population and > 50 years old, =6 months after completion of a primary COVID-19 vaccine series.
Australian Technical Advisory Group on Immunization (ATAGI) recommends COVID-19 booster vaccination with either Pfizer (Comirnaty) or Moderna (Spikevax), which are considered equally acceptable, for anyone aged 18 and older who completed their primary course of COVID-19 vaccination 5 or more months ago.
On December 8th, 2021 in a press release by Pfizer-BioNTech said that preliminary laboratory studies demonstrate that three doses of the Pfizer-BioNTech COVID-19 vaccine neutralize the Omicron variant while two doses show significantly reduced neutralization titers. Data indicate that a third dose of BNT162b2 increases the neutralizing antibody titers by 25-fold compared to two doses.
Key Findings
December 3, 2021
The Therapeutic Goods Administration (TGA) has granted provisional approval to Moderna for the use of its vaccine in children (two 10µg doses) and as booster shot for adults (one 30µg dose) in preparation for the recent emergence of the Omicron variant. This is in addition to Pfizer, which was also recently approved.
The National Advisory Committee on Immunization (NACI) recommends that a complete series with the Pfizer-BioNTech COVID-19 vaccine (10 mcg) may be offered to children 5-11 years of age who do not have contraindications to the vaccine, with a dosing interval of at least 8 weeks between the first and second dose.
NNACI also recommends that children aged 5-11 years with a history of previous SARS-CoV-2 infection should be considered no longer infectious and symptoms of an acute illness should be completely resolved prior to vaccination.
Health Canada has authorized Moderna's COVID-19 vaccine (also known as Spikevax) to be used as a booster shot, using a half-dose of the vaccine.
Low grade evidence shows IgG and IgM antibody response correlates with neutralizingantibody titerand viral clearance, which is suggestive of protective humoral immunity inCOVID-19 patients with mild to moderate symptoms.
There is no available evidence with which to estimate the durability of this protective response. However, if the immune response to SARS-CoV-2 resembles that toward SARS-CoV, this protective humoral immunity may persist for several years.
Higher IgG antibody titersand a robustresponse were noted in severe to criticallyill patients and were associated with lower viral clearance and a worse clinical prognosis.
Low grade evidence suggests that convalescent plasma treatment may improve the clinical status of critically ill COVID-19 patients(one case series with only five patients enrolled).
Badea, A; Reeder, B; Groot, G; Dalidowicz, M; Fox, L. Is there evidence that children under 18 should receive an mRNA vaccine booster/3rd dose? 2022 Feb 04, Document no.: EOC220102 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. (CEST table).
The CDC has released a recommendation that all adolescents 12-17 be offered booster vaccines using only the Pfizer COVID-19 vaccine, at least 5 months following the primary series
The CDC guidelines follow the review of unpublished Israeli data of 12-15 year olds vaccinated 5-6 months prior showing an equivalent infection rate to unvaccinated, and that those who receive boosters are at about 1/3 of the risk
Health Canada has not yet approved booster doses for general use in 12-17 year olds, however NACI has recommended that boosters, at least 6 months following the primary series, should be considered for the following groups within that age group
o Those with an underlying medical condition at high risk of severe illness due to COVID-19 (including those who are immunocompromised and received a 3-dose primary series)
o Those who are residents in congregate settings (e.g. shelters, group homes, quarters for migrant workers, correctional facilities)
o Those who belong to racialized and/or marginalized communities disproportionately affected by COVID-19
Notes
Updated Review cancelled due to insufficient evidence
Badea, A; Reeder, B; Groot, G; Dalidowicz, M; Fox, L. Is there evidence that children under 18 should receive the booster to increase their immunity? 2022 Feb 04, Document no.: EOC220102 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 8 p. (CEST rapid review report).
Dalidowicz, M; Fox, L. Is there evidence that children under 18 should receive the booster to increase their immunity? 2022 Apr 06, Document no.: EOC220102v002 ESR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 11 p. (CEST rapid review report).
Fox, L; Miller, L. What is known about hybrid immunity to COVID-19? 2022 May 18, Document no.: INF220501 ESR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 41 p. (CEST evidence search report).
Groot, G; Reeder, B; Muhajarine, N; Lee, S; Badea, A; Fox, L; Miller, L. What is known about hybrid immunity to COVID-19? 2022 Jun 06, Document no.: INF220501 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. (CEST table).