COVID-19 Update
Situation in Canada with Vaccinations and New Variants
- Nick Lin -
At the end of November and beginning of
December, the COVID-19 pandemic continues to
persist around the world, including Canada.
As of December 9 in Canada, according to the
Public Health Agency of Canada (PHAC), there have
been 1,818,742 cumulative COVID-19 cases.
Worldometers reports that there are 31,197 active
cases and 1,760,830 people have recovered, and
29,863 people have died of the disease. Current
cases and vaccinations are shown in the two maps
below:
The changing levels of daily new cases and new
deaths since the start of pandemic are shown in
the two graphs below:
In the context of the Delta variant, which now
makes up the majority of current cases, and the
emerging Omicron variant, Dr. Theresa Tam, Chief
Public Health Officer of Canada, in her December
10 statement, noted:
"Today's updated longer-range modelling forecast
suggests that with our current levels of
transmission a resurgence of Delta variant cases
is forecasted for Canada, even without any
acceleration of the Omicron variant in Canada
[...]. The forecast also shows a possible
trajectory if spread of the Omicron variant were
to accelerate and replace the Delta variant as the
predominant variant in Canada. In this case [...],
it is possible we could have an even more rapidly
accelerating resurgence in cases. As well, while
there is still considerable uncertainty regarding
the potential for Omicron to evade immunity and/or
increase disease severity, any rapid resurgence in
cases could add additional strain to our still
fragile health care system. Until we know more,
Omicron's increased transmissibility and potential
for strong resurgence means we must approach the
coming weeks with an abundance of caution and at
the same time be prepared to act quickly to
control spread at the first sign of rapidly
accelerating cases."
As of December 9, the PHAC reports that cases of
the Omicron variant have been confirmed in seven
jurisdictions: Quebec, Ontario, Manitoba,
Saskatchewan, Alberta, British Columbia and the
Yukon Territory. Regarding the efficacy of
vaccines against this new variant of concern, Dr.
Tam explains:
"Despite the challenges ahead with the continuing
Delta-driven wave in Canada and emergence of the
Omicron variant, we have more and better
protections going into this holiday and winter
season than previously. Vaccines and our expanding
population coverage continue to give us an
advantage over this virus, and while some
reduction in protection is possible with the
Omicron variant, COVID-19 vaccines are still
expected to provide a level of protection,
particularly against severe outcomes. Hence,
vaccination including boosters, in combination
with layers of public health and personal
protections, continues to be essential to the
pandemic response in Canada.
"Since the start of the pandemic, there have been
1,823,009 cases of COVID-19 and 29,876 deaths
reported in Canada. These cumulative numbers tell
us about the overall burden of COVID-19 illness to
date, while the number of active cases, now at
31,295, and seven-day moving averages indicate
current disease activity and severity trends.
"Surveillance data continue to show significant
regional variation in COVID-19 disease activity
across the country. Nationally, daily case counts
are rising with high infection rates persisting in
many areas. During the latest seven-day period
(December 3-9), an average of 3,450 new cases were
reported, which is an increase of 22 per cent
compared to the previous week. Currently,
hospitalization and critical care admission
trends, which are lagging indicators, have
levelled off, but if infection rates accelerate,
trends could begin to rise again. The latest
provincial and territorial data show that an
average of 1,457 people with COVID-19 were being
treated in Canadian hospitals each day during the
most recent seven-day period (December 3-9), which
is five per cent lower than last week. This
includes, on average, 458 people who were being
treated in intensive care units (ICU), 1.6 per
cent less than last week and an average of 20
deaths were reported daily (December 3-9). Keeping
infection rates down remains key to avoiding
renewed increases in severe illness trends over
the coming weeks and months as well as to ease
longer term strain on the health system,
particularly in heavily impacted areas.
"While Delta continues to represent the vast
majority of recent COVID-19 cases in Canada, as of
December 9, 2021, there have been 87 cases with
the newly designated variant of concern (VOC),
Omicron, reported in seven provinces and
territories. As we continue to assess the
significance and impact of this new VOC, Canadians
are urged to remain vigilant and continue
maintaining layers of protection.
"Regardless of which SARS-CoV-2 variant is
circulating, we know that vaccination, in
combination with public health measures and
individual practices, work to reduce disease
spread and severe outcomes. In particular,
evidence continues to demonstrate that a complete
two-dose series of Health-Canada approved COVID-19
vaccines provides substantial protection against
severe illness due to the predominating Delta
variant, particularly among younger age groups.
Based on the latest data from 10 provinces and
territories for the population aged 12 years or
older, in recent weeks (October 24 - November 20,
2021) and adjusting for age, average weekly rates
indicate that unvaccinated people were
significantly more likely to be hospitalized with
COVID-19 compared to fully vaccinated people.
"Among youth and adults aged 12 to 59 years,
unvaccinated people were 32 times more likely to
be hospitalized with COVID-19 than fully
vaccinated people.
"Among older adults aged 60 years or older,
unvaccinated people were 16 times more likely to
be hospitalized with COVID-19 than fully
vaccinated people."
In her December 3 statement, Dr. Tam informed of
the National Advisory Committee on Immunization
(NACI) recommendations on third doses of the
vaccines to boost immunization. She stated:
"NACI has reaffirmed that the benefits of
receiving an mRNA COVID-19 vaccine continue to
outweigh any potential risks of experiencing rare
side effects following vaccination with an mRNA
vaccine, including the rare risk of
vaccine-associated myocarditis and/or pericarditis
most often seen in males aged 12 to 29 years. NACI
also recommends, and health authorities in Canada
agree, that immunization in those who are eligible
-- but have yet to receive their primary series --
should continue to remain the top priority, in
Canada and around the world.
"Regarding boosters, NACI considered emerging
evidence on waning protection of vaccines over
time and the safety and potential benefits of mRNA
vaccine booster doses. In the context of the Delta
variant, evidence suggests that vaccine
effectiveness against infection and symptomatic
disease decreases with time, and possibly against
severe illness as well, especially in older
individuals. No additional safety concerns were
noted following mRNA vaccine booster doses. The
rare risk of myocarditis and/or pericarditis
appears to be lower after the booster dose than
after the second dose of the primary series
--though higher than after the first dose. Based
on this, NACI has increased the strength of their
recommendations to now say --a booster dose of an
authorized mRNA COVID-19 vaccine should be offered
6 months or more after completion of a primary
COVID-19 vaccine series."
However, the World Health Organization (WHO) has
advised against the rollout of booster shots by
wealthy nations, saying that it comes at the
expense of access to vaccines by poorer countries.
The WHO and the Strategic Advisory Group of
Experts on Immunization and its COVID-19 Vaccines
Working Group, which "continues to review the
emerging evidence on the need for and timing of a
booster dose for the currently available COVID-19
vaccines," in an October 4 update concluded that:
"Introducing booster doses should be firmly
evidence-driven and targeted to the population
groups in greatest need. The rationale for
implementing booster doses should be guided by
evidence on waning vaccine effectiveness, in
particular a decline in protection against severe
disease in the general population and in high-risk
populations, or due to a circulating VOC [variant
of concern]. To date, the evidence remains limited
and still inconclusive on any widespread need for
booster doses following a primary vaccination
series.
"In the context of ongoing global vaccine supply
constraints, broad-based administration of booster
doses risks exacerbating inequities in vaccine
access by driving up demand and diverting supply
while priority populations in some countries, or
in subnational settings, have not yet received a
primary vaccination series. The focus remains on
urgently increasing global vaccination coverage
with the primary series driven by the objective to
protect against severe disease."
This article was published in
Volume 51 Number 12 - December 12, 2021
Article Link:
https://cpcml.ca/Tmlm2021/Articles/M510123.HTM
Website: www.cpcml.ca
Email: editor@cpcml.ca
|
