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January 11, 2021 - Dr. Archer's Update on COVID-19 response from the DOM and Medicine Program


All patients admitted to KHSC will undergo Covid-19 testing

1) Immunity from COVID-19 infection (and presumably vaccination) is long lasting! (click here).

2) Vaccine rollout to start soon at KHSC -likely beginning with long term care (LTC) residents and LTC staff

3) Ontario’s epidemic is not under control with a rate of test positivity of 7.7%, 1563 hospitalized patients (1/4 in ICU) and   3,338 new cases/day (click here).

4) COVID-19 rates remain stable in KFL&A (see update from KFL& A Public Health)

5) Canada’s COVID-19 epidemic: 665,256 total cases to date, 82,585 active cases and 17,209 deaths (a cumulative national case mortality rate of ~2%) (click here)

6) The COVID-19 global pandemic: A total of 1,942,713 million deaths and 90,806,606 million cases since the pandemic began(click here):

Regular reminders and updates:

  • KHSC bed capacity (not updated at time of note) 
  • Use the Mobile Screening Tool to expedite clinic visits 
  • KHSC visitor policy
  • COVID-19 testing at Beechgrove Community Assessment Center: (click here): 
  • Increased outbreaks and deaths in Long Term Care facilities (LTC)
  • COVID-19 in toddlers and young children: (click here). No new data since Dec 21st
  1. Infection (and presumably vaccination) with SARS-CoV-2 results in long lasting immunity:

There is now evidence that infection with COVID-19 provides long lasting protection against reinfection at the longest time point studied to date (8 months). 

Dan et al assessed measured both antibodies (which protect from reinfection with COVID-19) and cellular immunity (B and T lymphocyte mediated immunity, which reduces infection severity). They studied 188 people who recovered from COVID-19 cases. Their study extended up to eight months post-infection (click here). Most patients were from California and New York and 93% had mild infections and were never hospitalized. A blog by NIH director Francis Collins nicely summarizes the 3 types of antibodies that protect us (against SARS-CoV-2 and other infectious agents) (click here). Collins notes, “The first type is immunoglobulin G (IgG), which has the potential to confer sustained immunity. The second type is immunoglobulin A (IgA), which protects against infection on the body’s mucosal surfaces, such as those found in the respiratory and gastrointestinal tracts, and are found in high levels in tears, mucus, and other bodily secretions. The third type is immunoglobulin M (IgM), which the body produces first when fighting an infection. The literature shows that almost all COVID-19 patients mount an antibody response to the virus (seroconversion rates range from 91-99%). This is important because antibodies are the only component of immune memory that can provide sterilizing immunity. 

In addition to antibodies, there is a slower mechanism of immunity that is mediated by immune cells. This form of immunity can be protective (within days) even in the absence of circulating antibodies. These cells include circulating memory T cells and memory B cells. These cells mediated immune responses can limit the invasiveness of SARS-CoV-2 making any infection milder and limited to the nose and throat. This outcome is the primary goal of current COVID-19 vaccine clinical trials and is mediated by a team of cells, including memory CD4+ T cells, memory CD8+ T cells, and memory B cells.

Dan et al found that IgG antibodies targeting the virus’ spike protein were durable, with little decline in levels at 6 to 8 months after infection (see image below) . SARS-CoV-2 Spike IgG titers were relatively stable from 20-240 days. In contrast IgA and IgM antibodies declined rapidly 1-2 months after symptom onset.

Research data showing IgG antibodies

IgG antibodies are stable for 8 months post symptom onset (PSO)

In addition, memory B cells appeared within 16 days of symptom onset and steadily increased in the following 4-5 months. Thus, B cell memory to SARS-CoV-2 is strong and likely durable. What of the third arm of the immune system: T lymphocytes? CD8+ T lymphocytes appeared in 70% of people by 1 month and declined to 50% by 6 months. Even more impressive was memory CD4+ T lymphocytes. These immune cells occurred in 93% of patients at 1 month after symptoms and their numbers were essentially unchanged at 6 months. 

Thus, it appears that infection (and by inference vaccination) will indeed produce sustained immunity! There are very few reports of re-infection (although they always get lots of press). In Dan’s article they note two papers looking at over 4000 infections which noted no recurrent infection in 3-6 months of follow-up.

In conclusion, Dan et al nicely shows that almost all people with COVID-19 develop multiple forms of immunity (antibody and cellular) and this immunity persists >6 month post symptom onset (PSO)-see graph below.

research data graph with black, red and blue lines

This new work form Dan et al adds to two earlier papers (summarized in Dr. Collins’ blog). These earlier studies also showed that people who survive a COVID-19 infection continue to produce protective antibodies against key parts of the virus for at least three to four months after developing their first symptoms. In one study Iyer et al (click here) enrolled 343 patients, most of whom had severe COVID-19 requiring hospitalization. They examined antibody responses for up to 122 days after symptoms developed and compared them to antibodies in more than 1,500 blood samples collected before the pandemic began. They found that all three antibody types were present ~12 days after infection. IgA and IgM antibodies were short-lived but IgG antibodies persisted for the duration of the study (four months). The other study came from the University of Toronto. Isho et al (click here) looked at antibodies to the spike protein in blood and saliva taken from 439 COVID-19 infected people, some of whom required hospitalization. They found that antibodies against SARS-CoV-2 were present in blood and saliva. IgG levels peaked 2-4 weeks post infection but remained stable for the study duration (3 months). Because the antibodies are in the saliva this might offer and easy way to track immunity. 

All 3 studies found that IgA and IgM antibody levels drop rapidly. Because IgA and IgM antibodies decline more quickly, testing for these different antibody types also could help to distinguish between an infection within the last two months and one that occurred earlier. Such details are important for filling in gaps in our understanding COVID-19 infections and tracking their spread in our communities.

Bottom line: Immunity produced by infection with SARS-CoV-2 is durable for at least 8 months and likely much longer. This should also apply to vaccines which is very good news!

2) Vaccine rollout to start soon at KHSC: KHSC is a regional vaccine distribution site. Vaccinations will likely start this week with the prioritization of administration guided by provincial mandates. This will mean the initial vaccines will likely go to staff and residents of long term care facilities. However, I encourage people to remain patient, as vaccine supply arrives the vaccine will quickly move to frontline staff, vulnerable population and patient cohorts, and then on to the general population.

Important factors that guide the vaccine team are that:

  1. The clinic will run 7 days/week. 
  2. No doses will be wasted. Any reserve vaccine capacity will be used to vaccinate heath care workers on an on call basis.
  3. KHSC is a regional centre for vaccine distribution so equitable access will be ensured for LTC workers and health care workers at other hospitals and clinics.

In terms of managing expectations: information flow re: timing of vaccine distribution is controlled at a governmental level beyond KHSC. I apologize for the lack of detail in my note but will share information once its available and deemed reliable. Also, a reminder that vaccine supply will initially be insufficient to meet the pent up demand and patience will be required as we vaccinate people in accordance with provincially determined prioritization guidance!

syringe and needle in bottle of vaccine

3) Ontario’s epidemic is not under control with a rate of test positivity of 7.7%, 1563 hospitalized patients (1/4 in ICU) and 3,338 new cases/day (click here).Ontario has had 219,120 COVID-19 cases 3,338 new cases since yesterday. There has been a slight reduction in our positive COVID-19 test rate from 9.7% on Monday to 7.7% today. Ontario’s provincial rate is 1474.1/100,000 population, 5-times higher than in KFL&A (287.2 cases/100,000 population).

table of current Ontario data on Covid-19

Ontario’s pandemic at a glance Jan 11th 2021 (click here)

COVID-19’s large second wave in Ontario is resulting in rising rates of hospitalizations (1563 in hospital today with 387 in ICU beds). Most patients with COVID-19 are cared for on Medicine wards (gold below) and the balance are in ICU (black line in graph below) (click here). This ~4/1 ratio of ward to ICU admissions has been fairly constant throughout the pandemic. The government need to be mindful of this fact as they distribute resources to support pandemic care. Their rhetoric often to focus on supports for Emergency Departments and Critical Care Units (which are important) and too often fails to mention Medicine Units, such as Connell 3 at KGH, which 75% of COVID-19 care is provided.

graph showing increase in hospitalization and ICU cases

As can be seen in the graph below most cases of COVID-19 are in people under age 60 years, whereas most deaths (gray portion of bar graph) are over age 60 years. The infections are slightly more prevalent in women than men.

bar graphs showing cases by age and gender

The viral reproduction rate (R0) remains relatively stable but has not yet collapsed below 1.0 (see graph below), a desired inflection point that will mark a turning point in dealing with the virus and indicate we are winning the war on COVID-19). 

graph showing how many people will be infected by one person with covid

Peel (on Toronto’s western border) remains the hot spot in Ontario with 2835.7 cases/100,000 population (click here)Toronto’s prevalence remains high at (2,198.2 cases/100,000 population, ~3X the rate 1 month ago (711 cases/100,000) and ~9 times higher than Kingston). Windsor (2295.3 cases/100,000 population) and Ottawa (1088.2 cases/100,000 population) remain hotspots. Eastern Ontario, around Cornwall, continues to rise rapidly (923.8 cases/100,000). These hotspots, which include much of Ontario’s population, have rates 4-10 times higher than KFL&S, which is why elective travel to Kingston from these areas should be avoided.

Neighborhood variation in COVID-19 in Toronto: Most of Toronto’s neighbourhoods are COVID-19 hotspots and have a cumulative prevalence of over 1000 cases/100,000 population (click here).

photo of Toronto waterfront from the water showing cn tower and rogers centre

Toronto remains a collection of neighbourhoods with vastly different COVID-19 realities due to differences in social/economic, racial and health circumstances. Although COVID-19 is increasing in the city as a whole, case load is widely variable amongst Toronto neighbourhoods. Since the pandemic began the Thistletown-Beaumond neighbourhood has had 6496 cases/100,000 residents, ~ 10X the burden of COVID-19 in the Beaches neighbourhood (612 cases of COVID-19/100,000 residents). When one examines recent cases (i.e. those diagnosed since December 21st), case prevalence is still concerning-ranging from 93 cases/100,000 residents in Forest Hill South to 1256 cases/100,000 residents, in Humber Summit (click here).

We should avoid elective travel to and from these hot spots from lower prevalence areas, like Kingston.

4) COVID-19 rates remain stable in KFL&A (see update from KFL& A Public Health)

The total number of cases in KFL&A since the pandemic began is now 626, not counting the prison outbreak. There are currently 52 active cases in KFL&A, similar to last week. There was 2 COVID-19 patients hospitalized at KGH and we have had one death. In the last 4 days we have done 2660 tests for SARS-CoV-2 and 1.5% of tests were positive. There are 111 active cases in SE Ontario.

table showing status of Covid-19 in KFL&A

Table showing the status of COVID-19 in in KFL&A (which appear to be stable)

graphic showing the new cases in KFL&A

Graphic showing the new cases in KFL&A (still slowly rising but relatively stable)

Bottom line: The vaccine will ultimately protect us; however, it will take months to get a critical mass of Canadians vaccinated. Meanwhile we have to rely on good public health practices (as outlined by provincial lockdown). This is the final leg of a marathon and the next 3-4 months will challenge us all to remain patient and follow policies that have harsh financial and social consequences. However, there is light at the end of the tunnel in the form of the vaccines.

3d picture of hall showing depth and with arches along each side

5) Canada’s COVID-19 epidemic: 665,256 total cases to date, 82,585 active cases and 17,209 deaths (a cumulative national case mortality rate of ~2%) (click here) We have had 665,256 cases of COVID-19 in Canada since the pandemic began. Our second wave of active cases (orange line) has yet to reach a clear plateau (and certainly has not begun to decline). 84.6% of all cases have already recovered. There has been a ~2% national mortality rate amongst people diagnosed with COVID-19. Most cases of COVID-19 in Canada have been (in descending order), in Quebec, Ontario, Alberta and BC (top left below). Canada has done almost 20 million COVID tests with a cumulative positive test rate of 3.4%. Ontario is nearing the same case number as Quebec. remains the province with the most testing (~8.5 million tests) and has a 2.54% cumulative positive rate). 

map of Canada highlighting and listing Covid19 data for Canada

COVID-19 in Canada: Jan 11th, 2021 

Rates of infection are high in all Western provinces (BC to Manitoba) but with introduction of more aggressive public health measures rates in these provinces have plateaued (which is the intended outcome of the Dec 26th Ontario lockdown). Thus far rates in Ontario and Quebec (home to almost 63% of all Canadians) have not hit a plateau (see orange lines below). This relates (in part) to these two provinces being slow to ratchet up public health measures, several weeks later than western provinces. Rates of new infection remain low in all Maritime provinces. The outbreaks in the North have been controlled with few new cases in the NWT, Yukon, and Nunavut.

line, bar and circular graphs showing rates of new infection in Ontario

Graphics above show that Ontario rates of new infection (orange line) continue to increase, indicating we have yet to see effects of Dec 26th 2020 lockdown. Also note the unprecedented rise in hospitalizations (lower panel)

6) The COVID-19 global pandemic: A total of 1,942,713 million deaths and 90,806,606 million cases since the pandemic began (click here): The number of cases has increased over 5-fold since the beginning of August, 2020, when there were 16,296,790 cases globally. The pandemic hot spots are in the USA, India, Brazil, and Russia, with the UK, France and Turkey in hot pursuit! (click here). 

world map and lists ranking countries with highest covid 19 numbers

Rising global COVID-19 burden and death rate: Jan 11th 2021

The USA with 22,575,606 cases and 375,838 deaths tops the COVID-19 list and accounts for ~24.9% of the global pandemic (up from 21% pre-Christmas). The USA only accounts for ~4% of the world’s population (see below). There are as many cases in America as in India, Brazil and Russia combined! The COVID-19 active case map (above) shows the high incidence of infection in the US and South America, as well as in Europe (the bigger the salmon-colored dot the higher the active cases/100,000 population). Note the graph at bottom right (white) shows rising deaths/day. The ONLY solutions to this are adherence to public health measures and rapid, mass vaccination.

USA positive test rates and extension of border closure (click here): Thirty two (32) US states have positive test rates >10%! The USA, which has an average positive test rate of 13.6% (click here); however both countries are doing much worse than prior to Christmas (when Ontario’s rate was <5%). Ontario’s rising rate of positive tests is similar to rates in a number of states. However, rates of positive testing in the USA are extremely variable by state (as are public health policies!). California has a positive test rate of 13.7% whilst South Dakota remains at a staggering 33.6% rate of test positivity today. For snowbirds-rates in Florida remain high (13.7% today)-see below. 

graph showing Florida covid 19 cases from May 2020 to Jan 2021

The US-Canadian border closure has been extended until at least Jan 21st, 2021 (click here). That said, Canadians can still fly to America (although certain rules apply) and as discussed in my note in early December, Canadian citizens can return to Canada from America, with a number of requirements, including quarantine) (click here).

photo of US and Can flag attached at the ends and text stating extension of border closure

Regular reminders

KHSC bed capacity and preservation of elective care despite lock downBed capacity has changed little since Monday when it was 110 (107 today). We have 47 ventilators available. Our ICU capacity remains extremely limited (by non-COVID-19 cases). We are only reducing elective care to the smallest extent required, ensuring we provide care to the 99% of patients who do not have COVID-19. We recognize that the term “elective care” is really a misnomer-many of these “elective” patients have cancer and other serious disease which will not tolerate delay in care. We are not reducing cardiac work, as just one example, as much of this work is urgent and delay would be life threatening. We are encouraging physicians to optimize the use of e-health visits. We are also reminding patients who are coming to clinics in person that unless it is essential (and approved) they need to come alone, to minimize crowding in our clinic waiting areas. That said, it remains VERY safe to attend appointments at our clinics or to come to hospital for needed care!

We will however soon be taking patients transferred from Toronto to our center to assist as their COVID-19 admissions surge (stay tuned).

Use the Mobile Screening Tool to expedite clinic visits: Complete the COVID-19 pre-screening tool here and you will be able to “skip the line”: One way to safely expedite entry of patients into our facilities is to have all patients complete our pre-screening questionnaire before their clinic visit. This will screen out people who are sick and expedite entry to the facility for everyone. Reducing lines waiting to enter the clinics will be particularly important as colder weather arrives. The mobile screening tool only takes a few minutes to complete and you will receive an email with confirmation to bring with you, along with your appointment slip, in printed form or on your mobile device. To complete the mobile-screening in English, click here and in French, click here.

photo finger scrolling on smart phone showing screenshot of KHSC covid19 prescreening app

KHSC visitor policy: If a family member is coming in from a high prevalence area they cannot enter KHSC (i.e. they will fail the screening question). There are exceptions made for exceptional circumstances and this family presence policy will be updated by the end of the week (to make it clear who grants final decisions on exceptions that allow access). One of the hardest aspects of COVID-19 care in the hospital is the need to restrict visitors to ensure we don’t import COVID-19 into the hospital. A very few cases of COVID-19 can paralyze the hospital, particularly if they are brought in by visitors and then spread undetected. All details on the policy can be found using this link (click here). 

COVID-19 testing at Beechgrove Community Assessment Center: (click here): All COVID-19 test must be scheduled appointments (versus walk in). Appointments can be scheduled using our on line scheduling system. Before booking a test, individuals should complete the online tool to determine whether they qualify for testing (click here). The Beechgrove Complex is south of the King St. West/Portsmouth Avenue intersection. Signage will direct people through the Complex to the Recreation Centre building at 51 Heakes Lane for walk-in testing. Operating hours: Testing hours will return to 9 a.m. to 4 p.m. daily. To be tested you will require: A valid Ontario health card or a piece of photo identification. You must also wear a mask and maintain physical distancing at all times while in the walk-in line (click here).

animated photo of female receiving nasal covid test and showing how far the swab goes inside the nasal cavityphoto of three young boys dressed up as doctors

Because health care workers (doctors and staff) are increasingly having to miss work because their children have been sent home from school or daycare with symptoms of a upper respiratory tract infection, we have arranged that their children can access expedited testing at Beechgrove . The goal of this service is simply to allow the healthcare worker to return to work as quickly as possible for the public good. The children of staff will be tested between 1230 -1300 by appointment, 7 days/week. The new program for families applies to children up to age 18, an includes children of staff and physicians who provide clinical care and service. Staff and physicians themselves should contact occupational health to book their testing appointment. To book an appointment for a child, KHSC staff should call 613-548-2376. Testing of clinical staff and faculty and their children is processed at the KHSC lab with an average turnaround time of less than 24 hours.

Increased outbreaks and deaths in Long Term Care facilities (LTC): We have 4060 LTC beds in KFL&A. As discussed in many prior notes, most COVID-19 deaths occur in people who are not only old but who are also frail and live in nursing homes and long term care facilities (LTC). As of today, the 2980 deaths in nursing homes (up 71 deaths since Thursday) account for ~60% of all deaths in Ontario, click here. There are also ~ 1502 active cases in LTC residents and 1260 of active cases in LTC staff! In the last month the rate of death amongst LTC residents continues to increase daily and is now >100/week! Outbreaks in nursing homes usually start with a person in the community (health worker or family) acquiring the infection and importing it into the facility. Thus, protecting LTCs is best done with a combination of reducing community spread of COVID-19 and ensuring single occupancy rooms in LTCs (as well as appropriate pay for PWS workers, provision of PPE and rapid testing capacity). It is because of these grim statistics that the province has prioritized vaccination of health care workers and residents of Ontario’s LTCs. 

COVID-19 in toddlers and young children: (click here). No updates since Dec 21st since on-site schooling does not resume until later in January.

Stay well! 


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