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April 29, 2021 - Dr. Archer's Update on COVID-19 response from the DOM and Medicine Program


Starting with a big Thank You to colleagues!

tweet thanking colleaguestweet thanking colleagues


  • Provincial stay at home order (click here) in effect until the May 20th
  • All patients admitted to KHSC will undergo Covid-19 testing and all people entering the hospital will be required to wear medical grade masks.
  • Ontario Website now open to book vaccines for people over age 40 for all people and is now open for people ages 18-44 in hot spots (click here). 
screenshot of covid vaccine appt registration page
  • Universal masking: All patients and visitors to KHSC will be provided with medical masks at the doors of KHSC (to replace their cloth masks upon entry). Please wear your mask beginning on the front steps Do not enter the building without your mask on. Please be polite to the screeners-they are there to keep us all safe!

1) KHSC has accepted its 100th COVID-19 transfer patient from Toronto-KUDOS Team ICU! KUDOS Team Medicine!

2) Economics of COVID-19-Good public health policy and good economics are actually aligned

3) KFL&A COVID-19: KHSC has 37 hospitalized patients with active COVID-19 and 15 patients recovering from COVID-19, all from the Toronto area (except one local case) and >40% of all residents over age 16 years are partially vaccinated (see update from KFL& A Public Health)

4) AstraZeneca Vaccine has a strong safety record (5 cases of VITT out of 1.1 million doses in Canada) and is recommended by Health Canada (click here): Canada records first VITT-related death 

5) World vaccine roll-out tops 1.08 billion people (click here)! The pandemic explodes in India

6) Ontario infection rates plateau with 3871 new cases and a fall in positive test rates (7.6%) but hospital capacity remains saturated in Toronto (click here(click here): 

7) Canada’s COVID-19 epidemic shows a plateau in new and active cases (down -8 and -7%, respectively) and hospitalizations; but deaths rose 9%; 13 million vaccines administered thus far (31.5% of population have received at least 1 dose) (click here) (click here): 

8) The global pandemic continues to escalate: ~150 million cases to date and new case rates on the rise, particularly in India (click here): Up almost 3 million cases since Monday!

9) COVID-19 Vaccines FAQ: New FAQ 1: Can I take a different second vaccine for COVID-19? (click here)

10) Continued Improvement in COVID-19 in Ontario’s Long Term Care facilities (LTC)…2 deaths in past week-evidence vaccines working: click here


1) KHSC has accepted its 100th COVID-19 transfer patient from Toronto-KUDOS Team ICU! KUDOS Team Medicine!

The graph below shows where COVID-19 patients are being cared for at KHSC. About half are cared for by Team ICU (red bars) and the other half cared from by Team Medicine (yellow and Green). A big thanks to Drs Dan Howes and Chris Smith for their Leadership in ICU and Medicine, respectively. This is an amazing story of people in our hospital stepping up to make things happen. From staff in IT and facility management, through our Incident Command team, nursing, respiratory therapy, administration, trainees and faculty, everyone has stepped up! While ICU and Medicine are managing most patients, a big thanks to colleagues in all our Departments-each has made major accommodations to their practice to make this rapid change in practice possible. 

graphs showing covid admissions at KHSC

COVID-19 care at KHSC

2) Economics of COVID-19-Good public health policy and good economics are actually aligned (click here),

While Canada has got somethings right we have made two costly mistakes-a tentative approach to lockdowns and a slow vaccine roll out. I had the pleasure of hosting Dr. Chris Cotton from the Queen’s Department of Economics at Medical Grand Rounds this morning. He approached both these issues from an economic perspective. Dr Cotton has been leading the charge to make information available to government on the economic impact of health policy decisions they are considering in dealing with COVID-19. It turns out what makes health sense also makes financial sense!

screen shot of Dr. Christopher Cotton and his MGR info

We know that stay home orders and lockdowns work to slow the spread of COVID-19. However, we also know they come at high cost-both economic, loss of jobs and GDP, and personal cost, causing isolation and strains on mental health as well as loss of income. One interesting initiative Dr Cotton has led is, called Canadian Shield (click here). This platform assessed how best to do lockdowns-predicting the economic impact of rapid and extensive responses vs more delayed and incremental responses. In his economic modeling Dr Cotton compared an early and comprehensive lockdown (red line) to a more intermittent and incomplete lockdown model (the latter being what we actually did in Ontario).

The graph from Canadian Shield (below) predicts that an early but comprehensive Ontario COVID-19 lockdown (blue) would have resulted in less loss of employment than our actual policy (red), with partial lockdowns, partial reopening and inevitable recurring lockdowns. The key to economic recovery is thus effective control of the spread of COVID-19. These economic data suggest that taking tough medicine up front to crush the curve is better than on-again, off-again shut downs.

graphs red and blue lines

Likewise, Dr. Cotton predicts that a 1 month delay in vaccination would have staggering economic costs (in addition to the high price on human health). Dr. Cotton’s modeling data suggest that no matter how we did the lockdown (pre-emptively or more reactively-), a 1 month acceleration of vaccination would have avoided loss of GDP. For clarification, the ‘reactive response’ scenario is one in which Canada’s provinces and territories ease restrictions during March and the beginning of April of 2021. In this scenario, a resurgence of the virus, possibly driven by new variants of the disease, forces governments to impose another round of lockdowns in late April and continuing into June. 

teal and grey bar graphs

Early vaccination is predicted to minimize the impact of lockdowns on Gross Domestic Product (GDP) and could have saved Canada $22 billion. 

screenshot of powerpoint slide with graphs

Take home message-what makes sense (for health) also makes dollars!

3) KFL&A COVID-19: KHSC has 37 hospitalized patients with active COVID-19 and 15 patients recovering from COVID-19, all from the Toronto area (except one local case) and >40% of all residents over age 16 years are partially vaccinated (see update from KFL& A Public Health)

Our local situation is improving. Cases in SE Ontario have dropped 50% in the past week and we now have 227 active cases in SE Ontario, with 76 cases in KFL& A (see below). 

blue bar graph with red lines

New cases in SE Ontario have declined by 50% in the past 2 weeks due to vaccines and compliance with public health measures (slide courtesy of Dr. Evans)-April 29th 2021

The total number of cases in KFL&A since the pandemic began is 1267, not counting the resolved prison outbreak or people from other regions. This is up 26 cases since Monday, with most cases being young people, associated with Queen’s University outbreaks. As part of the provincial tertiary care system we have changed our hospital status overnight, doing our duty and filling ICUs and Medicine beds with COVID-19 patients from Toronto, which is overwhelmed. This is the right thing to do! We now have a paradox: Our hospital has the inpatient composition of a hot spot while local epidemiology is less dire. We will get through this and will be rightly proud of our role in helping to defeat COVID-19.

table of kfl&a covid data

Relative stability in KFL&A-but community spread continues, mostly amongst young adults

We have 37 patients with active COVID-19 in hospital at KHSC (red bar-graph on left below). Twenty people are in critical are beds (red bar below) and 17 are in Medicine beds with 15 more individuals who have recovered from COVID-19 (see green bar on graph below). I am happy to report we have bed capacity (177 beds) and ventilator capacity (22 ventilators) to continue to support local care of patients. The Medicine program remains busy with 173 patients in hospital. 

various graphs showing what beds are occupied at KHSC

KHSC bed capacity- (top left)-people with COVID-19 (red bar) or recovering from COVID-19 and no longer infectious (green bar)

There have only been two deaths of KFL&A resident since the pandemic began but we have had several deaths at KHSC of non-resident patients. In Leeds Lanark Grenville county there have been 58 deaths with 8 deaths in Hastings-Prince Edward County. 

In the past 4 days KFL&A has done 2145 COVID-19 tests with a rate of positive tests of 1.6%, roughly 20% of the provincial rate. Positive test rates are in modest decline locally (see green line below). Most new cases in KFL&A are caused by a variant of concern (i.e. mutant virus) including many double mutant viruses. These variants are more infectious and may be more lethal.

various line graphs of colour tracking covid test positivity

Rates of test positivity stable in SE Ontario April 29th (slide courtesy of Dr Gerald Evans)

COVID-19 is still actively spreading in our region mostly among young adults, with the latest outbreak being amongst students at Queen’s University (click here). This is a reminder that we are quite literally NOT IMMUNE. There has never been a more pressing need for following public health measures and to get vaccinated. 

On a more positive note, over 73,000 KFL&A residents have already been vaccinated (>40% of all residents)! Interestingly we have also vaccinated over 12,000 people who do not live in KFL&A! While good progress has been made in vaccinating older residents of KFL&A, less than 20% of those groups most often infected (<age 40 years) have been vaccinated, as we follow provincial vaccine administration guidelines that focus on vaccination of older populations first.

table and graphs showing outcome of phase 2 vaccinations

Great progress has been made in vaccinating the residents of KFL&A: 40.6% of residents over age 16 years have had at least one vaccine dose

4) AstraZeneca Vaccine has a strong safety record (5 cases of VITT out of 1.1 million doses in Canada) and is recommended by Health Canada (click here): Canada records first VITT-related death 

Update: Canada has had the first death attributed to VITT reported in a previously healthy 54 year woman, Ms Francine Boyer, in Quebec (click hereFollowing her vaccination, Ms Boyer suffered from severe fatigue and headaches. She was hospitalized locally and then transferred to the Montreal Neurological Institute but died two weeks post vaccination. Despite this tragic death the benefits of this vaccine, and all other COVID-19 vaccines, clearly outweigh the risks (discussed below).

All drugs and vaccines have side effects that can cause harm or even death. Whenever a treatment is administered a doctor and a patient are essentially agreeing that the benefits outweigh the risks. In this regard, one needs to understand the magnitude of the risk vs the benefit. To provide some perspective on the low risk of developing this rare blood clot after the A-Z vaccine there have been five cases of VITT in Canada out of more than 1.1 million shots administered(two in Ontario, and one each in Alberta, Quebec and New Brunswick). Four patients who developed VITT are recovering at home (click here).

The risk of developing a blood clot simply from being female far outweighs risk of developing a clot from taking a COVID vaccine. Women age 15-45 are more at risk for blood clots just based on their sex (1 in 3,300 risk of a clot). Many women choose to use birth control pills and this doubles their risk of clot to 1/1600. In contrast the risk of a clot after the Astra Zeneca vaccine is 1-4/million risk. Moreover, the vaccine will completely protect you from the much higher risk of contracting or dying from COVID-19. In the United Kingdom, where 20 million doses of AstraZeneca have been administered as of April 1st, there have only been 79 cases of blood clots likely linked to vaccination and <10% of these people have died (click here). The math clearly favours taking the vaccine. The Astra Zeneca vaccine has been reviewed again by Health Canada and its strong safety record has been confirmed. Health Canada once again recommends its use to stem wave 3 of COVID-19.

online news article regarding vaccines with photo of doctor administering vaccine in arm

However, for those that are interested in how the vaccine might cause clots and whether the problem is the antigen or the vector-read on! There are 2 new papers exploring the clotting disease that is associated in rare cases with the adenoviral vaccines (A-Z and J&J). 

Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination.Andreas Greinacher, al and Sabine Eichinger, M.D. New England Journal of Medicine, April 9, 2021. DOI: 10.1056/NEJMoa2104840 (click here). 

Thrombosis and Thrombocytopenia after ChAdOx1 nCoV-19 Vaccination. Nina H. Schultz, MD,PhD et al. and Pål A. Holme, M.D., Ph.D New England Journal of Medicine, April 9, 2021. DOI: 10.1056/NEJMoa2104882 (click here)

Both articles conclude that the unusual clotting events post vaccine are accompanied by thrombocytopenia (low platelet counts) caused by the unintended production of antibodies against a normal protein in the body (platelet factor 4 , PF4). These unwanted antibodies cause platelets to stick together and create blood clots in unusual places, like the brain, and they also reduce platelet counts which paradoxically promotes bleeding. The German study (see above) reported 28 cases of VITT, with a detailed description of the first 11 patients. They were aged 22-49 years and presented with serious thrombotic complications including cerebral venous sinus thrombosis (CVST), splanchnic vein thrombosis, disseminated intravascular coagulation (DIC), and pulmonary embolism. These problems occurred within 5-16 days of receiving the AstraZeneca vaccine. Six patients died. This group have now analyzed 40-50 cases, all of which show the presence of the PF4 antibodies. 

This combination of severe thrombosis and severe bleeding resembles another syndrome which is itself a complication of a widely used drug: heparin-induced thrombocytopenia (HIT). The new vaccine syndrome, named vaccine-induced immune thrombotic thrombocytopenia (VITT), and HIT are both diagnosed and treated in the same way, with the administration of intravenous immunoglobulins (IVIG) and anticoagulants. It is noteworthy we rely on heparin every day in the care of millions of patients; we did not discard it because of its ability to cause rare cases of HIT!

What about the Johnson & Johnson vaccine? The J&J vaccine resembles the AstraZeneca vaccine in that it uses an adenoviral vector to deliver the spike protein antigen. As with the Astra Zeneca vaccine the clot events with the J&J vaccine are also rare. We have not begun to use this vaccine in Canada but in the USA there have only been 6 cases of VITT out of 6.8 million administered vaccines. In my view, it is likely that VITT relates more to the vaccine vector than the spike protein antibodies since the 2 implicated vaccines use an adenoviral vector whereas all 4 vaccines generate antibodies to the spike protein and VITT has not occurred with Pfizer and Moderna vaccines, to my knowledge.

To summarize: The third wave in Canada is not yet controlled, we do not have adequate vaccine and quite frankly we do not have the luxury of not using the Astra Zeneca vaccine. If people make this choice there will be many unnecessary death and hospitalizations. The risks of the AstraZeneca vaccine causing VITT are rare…very rare! In contrast the benefits of the Astra Zeneca vaccine, which include an almost compelled protection from COVID death and severe COVID disease, are substantial. 

The bottom line: It would be dangerous policy and poor personal decision making to avoid taking the AstraZeneca vaccine (which results in ~1-4 chances/million of causing a clot) while COVID-19 itself confers a 2% risk of death, a 5-10 % risk of hospitalization and both these bad outcomes are prevented by the Astra Zeneca Vaccine. The numbers clearly give clear guidance: Take the first vaccine you are offered! This advice is supported by Federal and provincial guidelines.

5) World vaccine roll-out tops 1.08 billion people (click here)! The pandemic explodes in India

horizontal bar graphs of vaccines administered by country

1.08 billion vaccines administered globally-but distribution is hugely variable by country

Vaccines are they key to ending COVID-19 and the graph above shows some vaccine champs (USA in the lead). Canada’s vaccine roll out is slowly accelerating with >12.8 million doses administered. We are still paying a high price for our slow rollout in the form of an aggressive 3rd wave of COVID-19; but things are improving. There is real world evidence that the vaccines work. The graph below shows that in countries that have an effective vaccine roll out, like the UK and USA, rates of infection fall rapidly. In contrast, rates in India (where vaccinations are manufactured for export but few are delivered to Indian people) are skyrocketing.The per cent of Indian people vaccinated remains low and the country is paying a high price with people dying rapidly. Suffering is intensified by shortages of basic supplies like oxygen.

colourful line graphs showing daily new cases

The epidemic in India is a national and global crisis-note the low vaccination rate (left) and the rapidly rising rate of new cases (purple line on right).

India foreshadows what will likely happen in Africa. Very little vaccination has occurred in the African continent. We cannot end this pandemic without effective and equitable global vaccination. We need to turn our attention to international vaccine distribution as soon as possible.

For more on India: here is a sobering article from the Guardian (click here): The pandemic in India, like in most countries, is multifactorial. The epidemic reflects political dithering and ideology by leaders who deny the diseases’ magnitude and fails to plan for it. In addition India faces the stark economic realities of a country where poverty is common. Moreover, the emergence of SARS-COV-2 mutants, which are more infectious and probably more lethal. In addition, while vaccine nationalism is not in general viewed in a positive light; India has the opposite problem, massive export of vaccines to rich countries (like Canada) while the task of vaccinating their own population lags. India, has the world's largest vaccine-making capacity, and has donated or exported more than 66 million vaccine doses -it’s time to pay them back (click here).

article screenshot crime against humanityphoto of many people gathered close together in a lake

There is made in Canada, evidence that the vaccines are safe (no updates in past week). Here are the Canadian vaccine safety data for all vaccines as of April 16th (click here). After > 11 million vaccinations in Canada there have been 3,444 individual reports of vaccine side effects (0.045%). Only 464 side effects were serious (0.006% ) and there has been 6 presumptive cases of VITT.

The bottom line: If you get vaccinated you have less than a 6/100,000 risk of a serious allergic reaction and only one person has died from a COVID-19 vaccine in Canada. In return you get >90% protection from a serious COVID-19 infection and almost complete protection from a COVID-19 death. 

6) Ontario infection rates plateau with 3871 new cases and a fall in positive test rates (7.6%) but hospital capacity remains saturated in Toronto-see table below (click here(click here): 

number graphic of cases in ontario dataline graph

COVID-19 in Ontario April 29th 2021: An encouraging drop in the 7-day rolling average of new cases (right side of graph)

salmon coloured graph with 4 text boxes below and arrows

Wave 3 shows signs of plateauing in Ontario-with an encouraging 9% drop in hospitalizations

7) Canada’s COVID-19 epidemic shows a plateau in new and active cases (down -8 and -7%, respectively) and hospitalizations have plateaued; but both deaths rose 9; 13 million vaccines administered thus far (click here) (click here): 

map of Canada and surrounding waters

As is always the case, active cases rise several weeks before hospitalizations increase and resolve earlier (with stay home orders and vaccines). Thus it is no surprise that with stay home orders and rising vaccine rates in Canada we are seeing new and active case rates fall and hospitalizations plateau. As is usually the case the death rates have risen as ~1.6% of infected people succumb to the virus (see below).

salmon coloured bar graph

COVID-19 in Canada April 29h 2021

map of canada and various graphs and numbers

A plateau in wave 3-but rates of ICU admission have yet to decline

Canadians need to be aware that adherence to public health measures and acceptance of vaccines is critical. To date we have had 1,207,654 cases of COVID-19 since the pandemic began. The case mortality rate is 1.59% with 24,163 deaths. The current hospitalization numbers are much higher than in the 2nd wave of COVID-19 in late 2020 (with 4360 people in hospital today). Most infections are being spread by close contact. We have done ~32 million COVID-19 tests with a cumulative positive test rate of 3.76%. We all need to do our part to keep the health care system afloat so that people who do not have COVID-19 can continue to receive essential health care. The state of hospitals is worse than at any point in the pandemic. 

Rates of infection are high in most Canadian provinces, although most sharply increased in Nova Scotia and Nunavut, due in part to imported cases.Alberta’s high rates have yet to plateau.

colourful line graphs

COVID-19 cases rise in Nunavut.

Canada’s vaccination roll-out: 13 million vaccines administered thus far (31.5% of population have received at least 1 dose) (click here)-see below: To date, 14.6 million doses of COVID-19 vaccines (including Moderna, Pfizer-BioNTech and Astra-Zeneca) have been delivered and 89.3% of delivered doses have been administered. Thus, Canada’s vaccine gap has narrowed compared with last week. This vaccine gap is most pronounced in Ontario. The gap reflects recent arrival of vaccines but also our relative inability to quickly administer the vaccine to patients. 1,076,013 Canadians are fully vaccinated (click here).

8) The global pandemic continues to escalate: ~150 million cases to date and new case rates on the rise, particularly in India (click here): Up almost 3 million cases since Monday!

satellite image of earth from space

There have been almost 150 million cases of COVID-19 since the pandemic began, up almost 3 million cases since Monday! There have been 3,154,603 COVID-19 deaths since the pandemic began. Death rates are once again on the rise, as are new cases (orange graph below right). As usual rising deaths following rising case numbers by 3-4 weeks.

world map with yellow dots and ranking of countries leading in covid cases and deaths

New cases surge globally-orange graph bottom right

This is a reminder of the need for global vaccination. We will not end this pandemic until the entire world has access to vaccines. Until then we will continue to have the development of mutant viruses that not only hurt the unvaccinated people but threaten to defeat the protection conferred by vaccination. 

map of east Asia with yellow dots

Global COVID-19 April 29th 2021: India’s epidemic surges

Our next big challenge-India and Africa: We need to vaccinate the world-not just wealthy countries. This is not done just out of a sense of compassion and equity. Widespread vaccination, to the point of herd immunity, is necessary to stop viral mutation and immune evasion. India’s 3rd wave is a reminder of how fast a situation can deteriorate. Although India produces massive amounts of vaccine the per centage of Indian’s vaccinated is very low and the disease is overwhelming their health care system. There are reports of shortage not only of hospital beds but of basic medical supplies, including oxygen (click here). Mr. Modi has not helped, with a fondness for big crowds at his rallies and a lack of clear, science-based communication. 

screenshot of people in PPE carrying medical aid for India

Canada has appropriately offered aid to India (click here)!

The USA is now a success story: The pandemic is improving in the USA largely due to an effective vaccine program, with over ~244,000,000 vaccinations completed and a promise to have all Americans vaccinated by the end of April, 2021. America now has a 3.9% positive test rate, the lowest rate since data collection began! (click here; see below). The American turnaround should offer hope to Canadians-this should be us in 2-3 months!

line graphs

8) FAQs-answers to common questions about the COVID-19 vaccines:

grey human figure with hands up on head with orange questiuonmarks swirling around

New FAQ 1: Can I take a different second vaccine for COVID-19 (click here)

Chances are you can mix and match (i.e. one shot Pfizer; one shot AstraZeneca); but the science is not in yet. Researchers in Britain have launched a study to determine if it’s safe and effective to mix different vaccines (Pfizer and A-Z) that protect against SARS-CoV-2, the coronavirus that causes COVID-19. Participants will be allocated, at random, (rather like a flip of a coin) to receive one dose of one approved vaccine and a second dose of either the same approved vaccine, or a dose of a different approved vaccine. Participants will also be allocated at random to the timing of receiving these doses – some will get a boost dose four weeks after the first dose and some will get a booster at twelve weeks. Some believe that one vaccine type (mRNA vs adenoviral) may be better than the other in triggering the various aspects of the immune response. While we await the research results I would suggest taking the two doses of the same vaccine brand (but stay tuned for updates).

FAQ 2) I’m pregnant, should I get the vaccine? 

Vaccination is recommended for all women who are pregnant or breast feeding at any time in pregnancy unless there is some specific reason not to be vaccinated. The reason for this advice is that the mRNA vaccines for COVID-19 appear to be safe in pregnant women (click here) whereas COVID-19 has higher morbidity (is more severe) when contracted during pregnancy.

pregnant lady getting vaccineScreenshot of graphs and tweet from Dr, Archer

FAQ 3) New FAQ: Does one dose of vaccine provide protection from COVID-19? Short answer: yes (within 2 weeks). Pfizer vaccine confers 80% immunity within 2 weeks of first shot (click hereA real world study by the U.S. Centers for Disease Control and Prevention (CDC) evaluated the vaccines’ ability to protect against infection, including infections that did not cause symptoms. The study looked at the effectiveness of the mRNA vaccines among 3,950 participants in six states over a 13-week period. About 74 % of people had at least one shot, and tests were conducted weekly to catch any infections without symptoms. BothCOVID-19 vaccines developed by Pfizer-BioNTech and Moderna reduced risk of infection by 80% two weeks or more after the first shot. Immunity rises to >90% 2 weeks after the booster shot. This is reassuring, since Canada has spread out the interval from 1 month to 4 months, due to limited vaccine supply, as we try to get more people their 1st shot.

FAQ 4) If I have a solid organ transplant or I am a cancer patient should I have my second vaccine dose at the original interval? 

The short answer is yes (although it is not based on clinical trial data). Emerging “real world” data (aka experience) suggests that transplant recipients and active cancer chemotherapy patients (with specific treatment and timing considerations) are now eligible to have their 2nd dose of COVID-19 vaccine at the original interval (<30 days from dose 1); rather than the revised 16-week interval. KHSC is currently in the process of operationalizing this new recommendation (which was issued at noon today).

FAQ 5) Which vaccine will/should I get? The short answer is that all vaccines effectively prevent COVID-19 death and severe adverse outcomes-so take the one that you are offered. They are all safe. That said, the vaccine someone receives will depend on your age, where you live and where you are vaccinated. The AstraZeneca-Oxford vaccine, which has an overall effectiveness of 62%-vs >90% for Moderna and Pfizer, will be administered mostly through pharmacies and primary care clinics, as will the Johnson & Johnson vaccine (I suspect). This is the case because they both can be stored safely in a regular freezer (click here). The AstraZeneca vaccine is recommended for people between 18-64 years of age. The mRNA viruses (Pfizer/Moderna) are recommended for people over age 64 years. The advantages of getting a vaccine earlier (even if it’s a little less effective) outweigh waiting longer for a more effective vaccine. This is especially true since all vaccines seem to prevent death and severe COVID-19 complications. Emerging data show that the Astra-Zeneca vaccine is safe and effective in people over age 70 years (based on real-world data emerging from its use in the UK) (click here). In the recent US study it was over 90% effective in preventing severe COVID-19 and prevented death with 100% effectiveness!

FAQ 6) Which COVID-19 Vaccines have been approved by Health Canada? Currently Canada has 3 approved vaccines: Pfizer, Moderna, and Astra-Zeneca (as of last week). The Astra Zeneca vaccine was approved on Friday and may arrive as soon as Wednesday (click here). Canada is expecting 445,000 doses of this vaccine this week. The vaccine appears to prevent COVID-19 spread and severe COVID-19 pneumonia and death; however, it has the lowest effectiveness overall (62% protection).The J&J vaccine was just approved by the FDA in the USA (click here). It has not been approved in Canada yet but this is expected to occur in the next 2-3 weeks. The J&J vaccine has several advantages. In a study with people in 3 continents one dose of J&J was 85 per cent protective against the most severe COVID-19 illness and the safety profile was as good as other vaccines. The J&J vaccine is a single shot vaccine (unlike two shots for Pfizer and Moderna). In addition it can be stored in a simple office refrigerator, allowing it to be rapidly deployed in the community. The bottom line: All approved vaccines are protective against severe adverse outcomes and I would advise you to take the first vaccine you are offered!

FAQ 7) Does the vaccine work against new variants (mutations) in the SARS-CoV2 virus? Short answer is a qualified YES. The vaccines work albeit not quite as well for the variants. In the 144,000 participants in all randomized clinical trials of vaccines to date, those receiving any active vaccine had only 3 cases of severe COVID-19 (vs 37 in the control group). There were no deaths in people who were vaccinated with any of the vaccines versus 5 deaths in the control group. Even though absolute protection is slightly less for UK and South African variants the vaccines (including the AstraZeneca vaccine and J&J) prevent serious adverse outcomes (like hospitalization and death). Thus, despite variant viruses the vaccines are lifesavers!

FAQ 8) I’m on a blood thinner, can I be vaccinated for COVID-19? Short answer YES. Here is a more detailed answer from an Canadian agency with expertise on the use of blood thinners, Thrombosis Canada

memo from thrombosis canada re getting a vaccine if on blood thinner

FAQ 9) I have a history of allergic reactions, can I be vaccinated for COVID-19? Short answer YES. Out of ~1.8 million vaccinations there have only been 21 reported episodes of anaphylaxis (the most serious type of allergic reaction). Most (70%) of these events occurred within 15 minutes of the vaccine (which is why you will be monitored for this period of time post vaccine). There were also 83 cases of non-anaphylaxis allergic reaction after Pfizer-BioNTech COVID-19 vaccination with symptom onset within a 0–1-day risk window. Most (87%) of these allergic reactions were classified as nonserious. Thus, the risk of severe allergic reactions to the Pfizer vaccine are low and manageable. Allergy testing is NOT necessary prior to COVID-19 vaccination even in people with history of allergies. It is important note that none of the people who developed anaphylaxis after vaccination died and most did not have a prior history of anaphylaxis (see table below). The incidence of anaphylaxis is lower still with the Moderna vaccine. The Canadian Society of Allergy and Clinical Immunology has recently updated and reinforced this advice (see Tweet below):

tweet re allergic reactions and vaccine

The adverse effects of the COVID-19 vaccines in clinical trials are similar in vaccinated people vs people who got a placebo-saline injection except for: local pain at the vaccine site and increased muscle ache and headache, all of which were more common with the vaccine but were short-term (see below). This is a very good safety profile relative to other vaccines.

table listing side effect of Pfizer vs placebo

The CDC does advise against the use of the two mRNA vaccines for a very select group of people with the following allergy histories (click here):

  • Severe allergic reaction (e.g., anaphylaxis) after a previous dose of an mRNA COVID-19 vaccine or any of its components
  • Immediate allergic reaction of any severity to a previous dose of an mRNA COVID-19 vaccine or any of its components (including polyethylene glycol [PEG])*
  • Immediate allergic reaction of any severity to polysorbate (due to potential cross-reactive hypersensitivity with the vaccine ingredient PEG)*

FAQ 10) I’m immunosuppressed, should I get vaccinated? This question has a less clear answer. First, be reassured is no virus (dead or alive) in the Pfizer or Moderna vaccines so it is not possible for a person to get infected from the vaccine. However immunosuppressed people were not included in the initial clinical trials. That said, they probably are safe to be vaccinated but this is more a matter of expert opinion. In Canada the National Advisory Committee on Immunization (NACI) currently advises that the COVID-19 vaccine should not be offered to populations excluded from clinical trials “until further evidence is available.” However, they also say “an immunosuppressed person or those with an autoimmune disorder can still be vaccinated if a risk assessment deems that the benefits of vaccine outweigh the potential risks for the individual.” (click here).

The British Society for Immunology recently issued a statement indicating that vaccination is safe in immunosuppressed people (click here), albeit the resulting immune response may be weaker. They remind us that because there is no virus in the vaccine there is absolutely no risk of acquiring COVID-19 from the vaccine. Dr. Mike Beyak (gastroenterology) nicely summarized evidence from a registry of ~4500 patients who were immunosuppressed for their inflammatory bowel diseases (Crohn’s disease and ulcerative colitis). There was no increased risk of contracting COVID-19 in these 4500 patients. Apart for patients on prednisone, there was also no increased complications from COVID-19 when it occurred. Interestingly, some biologic therapies (antibody treatments for IBD) actually appear to reduce adverse outcomes in IBD patients who contracted COVID-19. This is not surprising since the truly bad outcomes in COVID-19 seem to occur in people who mount a hyper-aggressive immune response. Overall these data are good news for our many patients with rheumatoid arthritis, asthma and IBD who are on immunosuppressive therapies. However, since these people were not included in the vaccine clinical trials, it is advised they consult the physicians/clinic that is managing their care to inform their vaccine decision.

FAQ 11) How long can I wait after my first dose to get a second vaccine dose? It appears a second dose at day 42 is as effective in producing a neutralizing antibody response as when the dose is given at day 21 (the normal interval from dose 1). This more lenient 42-day interval is necessitated by our vaccine shortage and has been approved by Health Canada. 

syringe and needle drawing vaccine from bottle

FAQ 12) Can I contract a COVID-19 infection from the vaccines? This answer is simple-NO! None of the approved vaccines in Canada contain the virus itself. They do not contain live virus; they do not contain dead virus. Canada’s approved vaccines (from Pfizer and Moderna) contain only the messenger RNA (genetic code) to allow you cells to make the viral spike protein which then triggers your immune cells to build anti-spike antibodies which protect you. The Astra Zeneca vaccine is much the same but delivers the SARS-CoV-2 spike protein gene via a chimpanzee adenovirus-vector. The J&J vaccine also uses an adenoviral vector but again, there is no SARS-CoV-2 virus (not dead; not alive) in this vaccine (click here). So, while you might get a sore arm or a fever from vaccination this is just your immune system responding as it should; there is no chance of getting COVID-19. Obviously one could contract COVID-19 around the time of vaccination the normal way, before the vaccination’s protection develops (i.e. in the first 2 weeks after vaccination). 

FAQ 13) Are vaccines safe? Yes, serious adverse effects of vaccines are rare (occurring in only 167 of 1.4 million Canadians vaccinated). Most people get (at worst) sore arm at the injection site, fatigue, or fever, all signs the immune system is being activated. Based on the clinical trials and experience in millions of people who have been vaccinated world-wide we can be reassured of vaccine safety and efficacy. All the side effects (called adverse events and abbreviated AEFI) are tracked and reported by the government of Canada (see below). (click here) (last updated April 16th).

FAQ 14) Is it safe to increase the time span between dose 1 and 2 of the COVID-19 vaccine? Most vaccines are given with an initial dose and a booster dose 3 months later. The reason the COVID-19 vaccine regimen initially specified a shorter interval was simply the rapid pace of the clinical trials which compressed the vaccination interval. Regulators approved the vaccine based on the information that came from these trials. With time it is now clear that spacing out the interval up to 4 months is safe and effective. This longer interval between vaccines allows more people to get the first dose asap and as the data have shown, the first dose yields substantial immunity within 1-2 weeks. That said, once vaccines become more available it would be prudent to return to the initial interval between vaccine doses. My second dose of Pfizer vaccine will occur 4 months after the first dose I received.

9) Sustained improvement in COVID-19 in Ontario’s Long Term Care facilities (LTC)…evidence vaccines working: click here

three senior citizens sitting around a table all wearing masks

Most COVID-19 deaths occur in people who are not only old but who are also frail and live in nursing homes and LTC facilities. While LTC residents account for only 5.3% of all cases in Ontario, they account for 51.8% of all 8029 deaths in Ontario. As of today, the 3,757 deaths in nursing homes account for ~46% of all deaths. There were 2 new deaths in LTCs due to COVID-19 in the past week. There are 41 active COVID-19 cases in LTC residents and 139 active cases in LTC staff, the lowest numbers in months. These numbers remain low and stable, which is testimony to the effectiveness of mass vaccination in a high risk population! For example a month ago we were seeing death rates of >100/week; now it is 0-2/week. These graph below shows the beneficial impact of the province’s decision to prioritize its limited initial vaccine supply of health care workers and residents of Ontario’s LTCs. Note the rapid decline in both staff (yellow) and resident (orange) COVID-19 case numbers coincident with vaccination!

line graph showing decline in cases in ltc since vaccines

How this to friends and family who are vaccine hesitant: Vaccines crush COVID-19 in LTCs: an awesome testimonial to the power of vaccines in vulnerable people

Regular reminders-On hiatus 

Stay calm, Stay informed, Stay Home, Stay Well! …. Get Vaccinated!!!

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