COVID-19 Research Scan

Research Scan: November 25, 2021

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  • On November 19, Health Canada authorized the use of Pfizer-BioNTech vaccine for children 5 to 11 years of age.
  • On November 15, Health Canada authorized the use of Moderna's COVID-19 vaccine for booster shots. The dose of the Moderna booster is half (50 µg) of the dose used in the primary series.
  • On November 16, Moderna submitted an application to Health Canada to authorize Moderna's COVID-19 vaccine in children ages 6-11 years. This age group will receive a 50 µg two-dose series, half the dose given to individuals 12 and older.
    • Phase 2 results of the KidCOVE have demonstrated 100% efficacy against symptomatic infection two weeks after the first dose. Vaccine efficacy against any SARS-CoV-2 infection, regardless of symptoms, was 80% two weeks after the first dose.
  • On November 16, Pfizer applied to the FDA for emergency use authorization of its antiviral pill, PAXLOVID. Unpublished data suggest that the pill reduces the risk of hospitalization by 89% if given within three days of symptom onset.  


  • A number of European countries are again experiencing surges in SARS-CoV-2 infections, exceeding previous daily case records, and are reimposing restrictions. Resurgences are not limited to countries with lower vaccination rates.


New Measures

Vaccination Rate (as of Nov 24)


On  November 12, Denmark reinstated its COVID-19 vaccine pass in bars, restaurants, cafes, and large events. Denmark lifted most of its restrictions by September 10, eliminating capacity limits, mask use, and the vaccine passport.

76% of the population is fully vaccinated

86.4% of the population 12+ is fully vaccinated


On November 22, Austria imposed a lockdown, closing non-essential shops and requiring people to work from home. This follows a November 15 lockdown of only unvaccinated people and a series of other restrictions that were first introduced September 14. The government plans to implement a nationwide vaccine mandate on February 1, 2022.

66.1% of the population is fully vaccinated

74.7% of the population 12+ is fully vaccinated



On November 15, Berlin and a number of German states have reintroduced restrictions on unvaccinated individuals, limiting access to restaurants, cinemas, museums and concert venues to those who are vaccinated or recently recovered.

68.1% of the population is fully vaccinated

76.5% of the population 12+ is fully vaccinated


On November 13, the Netherlands reinstated a partial lockdown that will last at least 3 weeks and requires non-essential retail to close at 6pm and bars, restaurants, and essential shops to close at 8pm. Sporting events will be held without spectators and people are limited to gatherings of four guests in their homes.

72% of the population is fully vaccinated

83% of the population 12+ is fully vaccinated


In Portugal, which has one of the highest vaccination rates in the world, the government plans to announce new measures to control rising cases on November 25.

86% of the population is fully vaccinated (last updated November 14)

Over 90% of the population 12+ is vaccinated (exact % cannot be calculated based on available data)


On November 6, Iceland reintroduced four weeks of restrictions including mandatory masks in public when physical distancing cannot be maintained, an 11pm curfew on restaurants, and rapid tests for events of 1500 or more. Further restrictions were introduced on November 12, including limiting indoor/outdoor gatherings to 50 people, a 10pm curfew on seating guests at restaurants, 75% capacity limits in gyms, spas, pools.

On November 16, Iceland had the highest single-day number of SARS-CoV-2 infections in the whole pandemic.

76% of the population is fully vaccinated

89% of the population 12+ is fully vaccinated


FDA authorizes use of Moderna and Pfizer-BioNTech boosters for all adults 18 and older

  • On November 19, the US FDA amended the emergency use authorizations of both the Pfizer-BioNTech and Moderna vaccines to authorize their use as boosters in all adults 18 and older. Previously, boosters were only authorized for adults 65 years of age and older and adults 18-64 who were at greater risk of severe disease or who had high occupational exposure.
  • In a meeting held on November 19, the CDC Advisory Committee on Immunization Practices (ACIP) unanimously voted in favour of recommending that people 50 and older and people 18 and older living in LTC, should receive a vaccine booster. ACIP also recommended that people 18-49 may receive a booster, based on individual risks and benefits.

Pfizer-BioNTech has 90.7% efficacy in children 5 to 11 years of age

  • Results of the ongoing Pfizer-BioNTech phase 2/3 trial in children 5–11 years of age (n=1,517 in vaccine group, n=751 in placebo group) demonstrate vaccine efficacy of 90.7%, seven days after the second dose, with 3 cases of COVID-19 in the vaccine group and 16 cases in the placebo group (Walter et al., NEJM). Children received two 10-μg doses administered 21 days apart. Phase 1 data suggest that the vaccines are safe and produce strong immune responses.  

Vaccinating children 5 and older could reduce cases by an estimated 9%

  • A pre-print modelling study out of the Netherlands evaluated the benefits of vaccinated children ages 5 and older on cases, hospitalizations, and deaths. The model estimates that lifting all non-pharmaceutical control measures results in a large wave of SARS-CoV-2 infections, but vaccinating those 5 years and older reduces cases by 8.7%, hospital admissions by 3.2%, and ICU admissions by 2.4% (Ainslie et al., medRxiv).


Increasing hospital strain leads to an exponential increase in excess mortality

  • A US modelling study looked at the impact of severe hospital strain on excess mortality using data from July 4, 2020–July 10, 2021. During the study period, increased ICU occupancy was associated with increased excess mortality 2, 4, and 6 weeks later. Based on this data, the model predicts that if ICU capacity reaches 75% nationwide, an estimated 12,000 excess deaths could be expected over the following two weeks. If hospitals exceed 100% ICU occupancy, an estimated 80,000 excess deaths could be expected (French et al., CDC MMWR).

COVID-19 increases the risk of stillbirth

  • A large US study looked at the frequency of stillbirth in 1,249,634 delivery hospitalizations during March 2020 to September 2021 and whether risk increased in the pregnant person had COVID-19. Stillbirths were rare, but pregnant people with COVID-19 were 1.9 times greater risk for stillbirth compared to those without COVID-19. Stillbirths occurred in 1.2% of deliveries with COVID-19 compared to 0.64% of deliveries without COVID-19 (DeSisto et al., CDC MMWR).

Automated text messages and remote monitoring is associated with reduced mortality

  • A US study looking at the impact of a remote monitoring program that included twice-daily automated text message check-ins found that enrollment led to a 68% decrease in the odds of death at 30 days from a COVID-19 test compared to patients who received usual care (Delgado et al., Annals Intern Med). The automated text messages asked patients to compare their current state to 12 hours previously. If patients felt worse, this triggered a subsequent text to assess breathing ability which triggered a phone call with a clinician within one hour.  


  • The WHO reported a 6% increase in weekly cases; the European region reported a 11% increase in weekly cases. Deaths in the European region increased by 3%. The highest number of new cases were reported in the US, Germany (a 31% increase), the UK, and Russia. The Delta variant continues to dominate, accounting for 99.8% of sequenced samples in the last 60 days (Weekly epidemiological update - 23 November 2021).