Telemedicine and other technologies are being adopted and tested to facilitate appointments over video/audio call, as well as to deliver various rehabilitation programs.
Telemedicine may be a solution that increases specialist and primary care providers’ capacity to serve more patients.
Many studies focusing on rehabilitation for certain post COVID-19 conditions, such as shortness of breath (dyspnea) and fatigue, emphasize physiotherapy as a key aspect in recovery efforts.
Most studies and reviews endorse adopting multi-disciplinary care pathways to address the broad range of post COVID-19 symptoms.
Alternate treatment methods, such as singing and vocal therapy, are being studied with preliminary data supporting these as potentially effective interventions.
Attentive rehabilitation programs with frequent follow-ups from facilitators addressing physical and psychological barriers to recovery often result in improved health related quality of life in patients.
Although many (?) care pathways have yet to be formally evaluated, many resources and guidance documents for care providers and patients are available online from reputable organizations, such as the WHO, and are frequently updated with new information.
Social media and other digital media sources have caused confusion amongst much of the general public and have greatly contributed to the sharing of misinformation about COVID-19 and post conditions, as well as vaccination safety and efficacy.
Hammond, B; Dalidowicz, M; Miller L; Groot, G; Reeder, B. Response to Long COVID: What are the Programs or accommodations to current frameworks? 2022 Jun 30. Document no.: EOC220303 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 21 p. (CEST rapid review report).
A case definition for long COVID has yet to be adopted but is referred to by the WHO as “usually 3 months from the onset of COVID-19 with symptoms and that last for at least 2 months and cannot be explained by an alternative diagnosis”; the CDC considers persistent symptoms, or the onset of long-term symptoms, =4 weeks after acute COVID-19 infection.
Many studies and systematic reviews refer to COVID-related symptoms that persist or emerge beyond 4 weeks of infection as consisting of two subsequent phases: 1) Ongoing Symptomatic COVID-19 (OSC; signs and symptoms from 4 to 12 weeks from initial infection) and 2) Post-COVID-19 Syndrome (PCS; signs and symptoms beyond 12 weeks) with respect to symptomatology, abnormal functioning, psychological burden, and quality of life.
Post Acute Sequalae of COVID (PASC) is often referred to in studies and systematic reviews and is commonly understood as “the presence of at least 1 abnormality diagnosed by (1) laboratory investigation, (2) radiologic pathology, or (3) clinical signs and symptoms that were present at least 1 month after COVID-19 diagnosis or after discharge from the hospital”. It can be further classified as short-term PASC as 1 month; intermediate-term, 2 to 5 months; and long-term, as 6 or more months after COVID-19 diagnosis or hospital discharge.
In previous reviews, we have referred to “long COVID” synonymously to the above terms (ie. OSC, PCS, PASC) but for clarity, will move toward using these specific terms as they appear in the literature as well as simply using the time frames reported in each study/review. For example, where needed, we have replaced “long COVID” with the more concise “PASC” or “symptoms beyond 4 weeks of infection”.
Recommendations set out in our 2021 report can be relied upon with an important update to follow-up times (previously 2-3 months). Now, a 4-week follow-up is recommended for diagnosing and managing any PASC, especially for patients who suffered severe acute COVID-19 manifestation, where severe typically refers to those requiring medical attention, such as hospitalization for respiratory difficulty, to manage symptoms during the acute phase. In addition, these follow-ups should include mental health assessments in addition to any relevant clinical testing in response to each patient’s specific symptoms.
The clinical care burden of ongoing COVID-19 symptoms (OCS) is significant in the 3 months after infection and can place great demands on primary care services. Both OSC and PCS have consistently been shown to affect a large portion of the population with complex and persistent challenges that will also place strain on healthcare systems. This involves:
o Complications pertaining to multiple care specialties, with 20-75% of individuals reporting at least 1 persistent symptom 12 or more weeks following COVID-19 diagnosis.
o Neuropsychiatric manifestations (or “NeuroCOVID”) such as smell/taste disorder, memory complaints, anxiety, depression, post traumatic stress disorder (PTSD), concentration difficulties, and sleep disturbances are reported in 20-50% of individuals beyond 4 weeks from infection.
Functional disabilities and incapacity to return to work has been reported in 5% to 90% of individuals, where some are unable to reach their pre-COVID employment level at 12 weeks or longer post-infection; this has the potential to impact all sectors, including various levels of healthcare.
A significant number of individuals suffer from severe clinical conditions, such as acute cardiac, lung, and kidney injury.
A key focus will be to support individuals and populations who experience other persistent yet less severe conditions and symptoms such as fatigue, dyspnea, and mental health challenges including depression, anxiety, and sleep disorders.
July 12, 2021
Long COVID-19 is likely to increase demands across the health system, including emergency departments, hospital admissions, primary care visits, specialist appointments, and home care and rehabilitation services.
The clinical care burden of long COVID-19 is the greatest in the first 3 months after infection (revised from ‘testing’ in the previous report) and is likely to place the greatest demand on primary care services.
Patients with severe COVID-19 illness are more likely to place longer-term demands (4-6 months after the infection) on specialist care due to respiratory, circulatory, endocrine, metabolic, psychiatric and unspecified conditions.
Groot, G; Reeder, B; Hammond, B; Badea, A; Howell-Spooner, B; Ellsworth, C. What are long COVID's demands on the healthcare system, and its severity of the illness? 2022 Jun 20, Document no.: EPM210602v002 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 23 p. (CEST rapid review report).
ECDC & WHO have released statements indicating that while a 4th dose may be beneficial to populations at highest risk of severe outcomes, marginal benefits for other populations may be outweighed by the opportunity and financial cost
Extensive analysis of data from Israel’s 4th dose campaign indicates that while protection against severe disease and death remains high following 3rd dose, the administration of a 4th dose significantly increases protection against infection and symptomatic disease, though this protection appears short-lived, with protective effects waning by 10 weeks
Israeli healthcare workers demonstrate an increase in immunity markers following 4th dose, but protection against infection remains low
In immunocompromised individuals (such as solid organ transplant patients and dialysis patients), receipt of a 4th dose of COVID-19 vaccine increases immunity marker titers, but non-responders continue to have a low likelihood of de novo seroconversion
March 31, 2022
Data from Israel of adults 60 years and older who received a 4th dose of mRNA vaccine found that the rate of confirmed infection decreased ~2 fold following the 4th dose, and the rate of severe illness decreased by ~4-fold in those who received a 4th dose versus those with 3 doses, both results were found to be statistically significant
NACI recommends a 4th dose at least 6 months following a 3rd dose for severely immunocompromised individuals who are not only at higher risk of severe outcomes, but also at higher risk of decreased protection over time following vaccination – this recommendation has been echoed by Public Health Ontario, the Northwest Territories Health and Social Services
The FDA has also authorized the use of the Pfizer mRNA vaccine as a 4th dose for adults over 50 years and those over 12 years with compromised immune systems
A small study of Israeli healthcare workers compared the incidence of COVID-19 in those who had received a 4th dose of vaccine to those who had received only three doses. It found that protection from Omicron infection was only slightly higher in the four-dose vaccine group compared to the three-dose control group (31% for Pfizer as a 4th dose, 11% for Moderna as a 4th dose), and that neither result was statistically significant. Breakthrough infections were mild, yet with high viral loads
Small-scale studies of solid-organ transplant and hemodialysis patients found that while a 4th dose increased antibody titers in most participants, those with severe immune deficiencies such as those taking anti-rejection medication were still unable to mount an immune response to vaccination – in addition, these studies have not assessed the presence or strength of functional immunity in these populations
Badea, A; Dalidowicz, M; Howell-Spooner, B; Groot, G; Reeder. B. What is the efficacy of a 4th booster dose for COVID-19? 2022 Jun 07. Document no.: EOC220304v002 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 12 p. (CEST rapid review report).
Current requirements for preoperative COVID-19 testing are highly variable across jurisdictions, with some requiring preoperative testing for all patients 24-72 hours prior to surgery and some not recommending testing of asymptomatic patients at all
Studies describing low rates of asymptomatic positivity are limited to early in the pandemic, prior to the widespread availability of vaccines and the emergence of variant strains. These studies show very low rates of asymptomatic positives when testing within 72 hours of surgery
Mixed evidence on safety of surgery in asymptomatic COVID-19 infected patients
Preliminary evidence indicates that it may be safe to discontinue asymptomatic preoperative testing, but there are too many unknowns that have not yet been addressed with regards to the impact of vaccination status and the altered pathophysiology associated with currently circulating variants
Badea, A; Groot, G; Reeder, B; Dalidowicz, M; Mueller, M. What is the evidence around testing for asymptomatic COVID on the day of surgery? 2022 Jun 06, Document no.: EOC220505 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 11 p. (CEST rapid review report).
There is substantial immunologic and increasing epidemiologic evidence that vaccination following infection further increases protection against subsequent illness among those who have been previously infected.
Laboratory studies indicate that hybrid immunity (i.e., immunity conferred by the combination of previous infection and vaccination) offers greater protection against COVID-19 infection.
A single dose of the AstraZeneca COVID-19 vaccine following SARS-CoV-2 infection induced a 2 to 3-fold increase in anti-Spike and -RBD IgG levels 30 days post-vaccination.
A study in Brazil found that hybrid immunity showed a modest increase in protection against symptomatic infection and waning over time.
Neutralising antibody titres against SARS-CoV-2 variants over 7 months following Pfizer vaccination in SARS-CoV-2-recovered and naïve healthcare workers resulted in substantially enhanced T-cell responses, anti-spike IgG responses and neutralising antibodies effective against SARS-CoV-2 variants in recovered participants.
Pfizer and Moderna vaccines were associated with greater IgG responses compared to Johnson & Johnson regardless of administration following infection.
Those with vaccine-after-infection or vaccine-breakthrough-infection had a more durable anti-spike-IgG response compared to infection-alone.
A study on healthcare workers from Oregon Health & Science University found enhanced immune responses after vaccination in COVID-19 recovered (hybrid immunity) compared with their naïve-vaccinated peers. However, the effects of post-vaccination breakthrough infections on humoral immune response remain to be determined.
Groot, G; Reeder, B; Muhajarine, N; Lee, S; Badea, A; Jagwani, M; 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. 11 p. (CEST rapid review report).
Significant evidence base demonstrates an increased risk of perioperative mortality in COVID positive surgical patients
Based on previous knowledge of preoperative pulmonary infections, as well as early clinical data, most professional associations recommend a deferral of at least 7 weeks from symptom onset or positive test to elective surgery
New evidence in light of the existing surgical backlogs indicates that those with asymptomatic or mild infections can proceed to minor, low-risk elective surgeries 4 weeks after symptom onset or positive test
Guidelines and frameworks indicate that timelines are only recommendations and individuals need to be assessed objectively for preoperative fitness, that the risks and benefits of both surgery and delay be discussed, and that shared decision making used between multidisciplinary care teams and patients
Badea, A; Groot, G; Reeder, B; Fox, L; Young, C. What is the evidence on timing and outcomes of elective surgery after a COVID infection? 2022 May 27, Document no.: EOC220504 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 11 p. (CEST rapid review report).
Rowein S, Singh S, Habbick M, Mehdiyeva K, Miller L, Gagneur, A, Groot G, Neudorf C, Camillo CA, Tokhmafshan, F, Muhajarine N. Motivational Interviewing for Vaccine Hesitancy. May 2022. Document no.: [12.1]. CoVaRR-Net Public Health, Health Systems, Social Policy Team, c2022.
Since the previous rapid review, a large amount of new research and reviews are available to draw upon. Many studies have addressed aspects previously identified as limitations such as the use of validated questionnaires, documenting pre-COVID health status, and control cohorts. Many studies now include only participants with RT-PCR verified infections and also focus on a range of disease severities from severe (hospitalized) to mild (managed in the community); PCR-validated infections ensure a higher quality of comparison between test-positive and control groups. Studies involving control groups contributed illuminating findings about prevalence and incidence of long COVID, which is lower than previous thought when compared to control groups. Comorbidities/factors that potentially indicate increased risk of developing long COVID-19 have been identified and widely agreed-upon, such as diabetes, cardiovascular diseases, obesity, and gender (female).
A case definition for long COVID has yet to be adopted but is commonly defined as COVID-related symptoms that persist or emerge beyond 4 weeks of infection with two subsequent phases: “ongoing symptomatic COVID-19 (OSC; signs and symptoms from 4 to 12 weeks from initial infection) and 2) post-COVID-19 syndrome (PCS; signs and symptoms beyond 12 weeks) with respect to symptomatology, abnormal functioning, psychological burden, and quality of life”. Long COVID includes both OSC and PCS.
It is estimated that 32% of non-hospitalized and 51% of hospitalized people experience Long COVID symptoms within 12 weeks of infection; however, higher estimates up to 92% have been reported in studies with a greater proportion in persons who were previously hospitalized. More than 200 symptoms affecting 10 organ systems have been identified in various reports or systematic reviews. Many patients (49%), experience at least one COVID-related symptom 12 months after infection (compared to 68% at 6 months).
For many persons, symptoms improve over time while others experience persistent and/or new symptoms. At 3 months post-infection the most frequently reported symptoms are fatigue (up to 98%), dyspnoea (up to 88%), headache (up to 91%) and taste/smell disorders (up to 58%).
Mechanism(s) leading to long COVID remain unclear, but these comorbidities/factors have been found to indicate potentially increased risk of developing long COVID:
o Age (60+)
o Greater number of symptoms during the acute phase of illness (typically 5+)
o Manifestation of specific symptoms
o Cardiovascular disease
o Obesity or high BMI
o Gender (female)
There is limited evidence to support the contention that vaccination lowers incidence of long COVID.
July 9, 2021
The frequency of Long COVID symptoms varies widely across studies based on populations studied, duration of follow up and methods of assessment of symptoms.
It is estimated that 1 in 50 persons experience Long COVID symptoms after 12 weeks; however, higher estimates up to 80% have been reported in studies with a greater proportion of persons who were previously hospitalized. A recent study of a mixed cohort of 96 persons found that only 22.9% had no symptoms at 12 months post diagnosis.
A wide range of symptoms affecting multiple organ systems has been reported. For many persons symptoms improve over time while others experience persistent and/or new symptoms. Among studies with the longest duration of follow up, the most frequently reported symptoms included fatigue (up to 65%), dyspnea (up to 50%), headache (up to 45%), anosmia/ageusia (up to 25%), cognitive memory/concentration (up to 39.6%) and sleep disorders (up to 26%).
Few studies estimated the duration of symptoms with estimates ranging from 2.2% for 6 months and 27% for 7-9 months.
The mechanism(s) leading to Long COVID remain unclear but those experiencing post acute sequelae tend to be older, have a greater number of symptoms during the acute phase of illness or manifest specific symptoms and live with multiple comorbid conditions such as obesity.
The lack of consensus on a definition of Long COVID contributes to marked variations in robust prevalence estimates.
A significant amount of evidence was produced since the previous review. This updated review was rewritten with extensive changes which have not been identified in red.
Hammond, B; Badea, A; Groot, G; Reeder, B; Howell-Spooner, B; Mueller, M. What is the incidence and duration of long COVID cases? 2022 Mar 31, Document no.: EPM210601v2 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 18 p. (CEST rapid review report).
Novavax was authorized for use in Canada February 16, 2022 and has also been authorized for use in 35 other countries as a 2-dose primary series given as an intramuscular injection, 21 days apart
Phase 3 trials of Novavax in US/Mexico and UK showed an overall vaccine effectiveness of 89.7-90.4% against all severity COVID infection and 100% against moderate/severe infection and death
In the US/Mexico, vaccine effectiveness against the dominant Alpha variant was found to be 92.6%, while in the UK, it’s effectiveness dropped to 86.3%
The most frequently reported local and systemic adverse events in both trials were tenderness and pain at the injection site and headache, myalgia and fatigue, respectively. Adverse events were mild-to-moderate and transient in nature, and more frequently reported following the second dose
A Phase 2 trial assessing safety and efficacy of Novavax in South Africa in adults 18-64 years during Beta dominance found a vaccine efficacy of only 49.4%, however, in subgroup analysis of only HIV negative individuals, efficacy rose to 60.1% overall, and 51% against the Beta variant. (). While efficacy against disease severity was not measured, the majority of infections reported in both the vaccine and placebo group were mild to moderate
Badea, A; Groot, G; Reeder, B; Miller, L. What is the safety/efficacy of the Novavax COVID-19 vaccine? 2022 Mar 10. Document no.: EOC220302 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 7 p. (CEST rapid review report).
6-month to 1 year survival rates of critical COVID-19 patients are similar to those of non-COVID-19 patients admitted to ICU
COVID-19 patients who have survived intensive care (ICU) admission are at risk of developing both post intensive care syndrome (PICS) and Long COVID. PICS includes impairments in physical, cognitive and psychological dimensions
Long-term survival follow up of COVID patients indicates that they experience similar levels of impairments in physical, cognitive and psychological dimensions as historical non-COVID reference populations.
The most common long-term impairments reported by COVID patients are persistent dyspnea/breathlessness, general weakness/fatigue and ongoing psychological symptoms such as anxiety, depression and PTSD
Badea, A; Reeder, B; Groot, G; Miller, L; Mueller, M. What are the one year outcomes for ICU COVID patients? 2022 Feb 18, Document no.: EOC220201 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 11 p. (CEST rapid review report).
There exists some ambiguity across jurisdictions and thus there is no clear universal case definition of COVID-19 hospitalization.
Public Health Ontario measures hospitalization as “the number of confirmed COVID-19 cases that reported ever being hospitalized during their infection”- i.e., all cases reported as ever being hospitalized during their infection.
The category “incidental COVID-19 hospitalizations” has been proposed. This refers to patients who are primarily admitted for other ailments and test positive as part of routine screening.
Some jurisdictions and health agencies have started differentiating between those who were admitted for COVID-19-related illness and incidental admissions. Ontario and Saskatchewan have begun using this category in their regular reporting of COVID-19 statistics.
New data from Australia, New Zealand, the US, and Canada indicate that 30 to 50 percent of COVID-19 hospitalizations are “incidental COVID-19 hospitalization” – 46% of COVID-19 hospitalizations in Ontario (as of January 11th, 2022) and 40% in Saskatchewan (as of January 26th, 2022)
Some expert opinions caution that such binary categorization may oversimplify clinical reality, and suggests also employing an ‘indeterminate’ category
Asamoah, G; Badea, A; Reeder, B; Groot, G; Muhajarine, N; Howell-Spooner, B; Young, C. What is the (case) definition of hospitalization for COVID-19 in similar jurisdictions? 2022 Feb 10. Document no.: CAC220101 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 9 p. (CEST rapid review report).
COVID-19 pandemic remains a challenge across various jurisdictions globally and with changing vaccine efficacy, and hesitancy, and COVID outcomes, various countries have since updated their definition of being fully vaccinated or immunized.
Government of Canada, for the purpose of international travel to qualify as a fully vaccinated against COVID-19 you must:
- have received at least 2 doses of a vaccine accepted for travel,
- a mix of 2 accepted vaccines or at least 1 dose of the Janssen/Johnson & Johnson vaccine, have received your second dose at least 15 calendar days before you enter Canada.
On 13th January, 2022, The Ministry of Health in Ontario recommended that the interval between the second dose third dose of COVID-19 vaccine be at least two months (56 days)
As of 16th January, 2022, the Centers for Disease Control and Prevention (CDC) in the United States has adopted the term Up to date with vaccination.
On 21st January, 2022, Chief Public Health Officer of Canada, Dr. Theresa Tam stated that the federal agency will re-examine the definition of fully vaccinated to include the booster dose in the primary vaccination series as being ‘up to date’.
On 4th February, 2022, the National Advisory Committee on Immunization (NACI) has issued an updated guidance on suggested intervals between previous SARS-CoV2 infection and COVID-19 vaccination
Jagwani, M; Reeder, B; Groot, G; Muhajarine, N; Mueller, M; Ellsworth, C. What are the latest health policy definitions of being fully vaccinated? 2022 Feb 10, Document no.: EOC220101 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 20 p. (CEST rapid review report).
Evidence to date of adverse events associated with mRNA COVID-19 vaccines are largely local reactions such as pain and swelling of the injection site, and systemic reactions of an allergic nature
Increased incidences of myocarditis and pericarditis have been observed, most often occurring in men under 30 years of age, and most often after the second dose of mRNA vaccine, with more occurrences following the Moderna COVID-19 vaccine versus Pfizer, however all cases appear to resolve
To date, there is no evidence indicating a negative effect on the immune system from the administration of multiple doses of mRNA COVID-19 vaccines
Badea, A; Reeder, B; Groot, G; Miller, L; Mueller, M. What are the harmful/adverse effects of multiple doses of COVID-19 mRNA vaccines? 2022 Feb 04, Document no.: EOC220103 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 10 p. (CEST rapid review report).
The diagnostic accuracy of Rapid Antigen Tests (RAT) has been widely studied in various applications and in diverse populations.
Sensitivity, in the order of 75% in pooled estimates, is significantly influenced by the presence or absence of symptoms, viral load, and the timing of sampling relative to the onset of symptoms.
Specificity, in the order of 99% in pooled estimates, is consistently high across tests, populations, and sampling methods.
Post-test probability of being an infectious case following a positive test is highest in individuals with a high pre-test probability (population prevalence > 5%), such as those with COVID-19 symptoms, and those in settings with a high level of community transmission. Here, the positive predictive value is in the order of 95%. However, when used in settings with a lower pre-test probability (population prevalence < 0.5%), as in screening asymptomatic individuals, the positive predictive value is considerably reduced, as low as 25%.
Post-test probability of being an infectious case following a negative test is less than 1% (negative predictive value > 99%) in all settings except those with the highest levels of community transmission.
Badea, A; Reeder, B; Groot, G; Muhajarine, N; Minion, J; Miller, L; Howell-Spooner, B. In real world settings, what is the validity of Rapid Antigen Tests (RATs) in identifying SARS-CoV-2 and how well do they predict disease? 2022 Jan 12, Document no.: EOC211201 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2022. 15 p. (CEST rapid review report).
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.
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.
Omicron first detected in Botswana and South Africa at the end of November 2021, classified as a variant of concern by the WHO and CDC by December 1st, 2021 after rapid spread to multiple areas of the world, and evidence of community transmission
Preliminary data indicates increased transmissibility of Omicron compared to the currently dominant Delta
In-vitro data indicates a significant reduction in neutralization titers of vaccinee sera – however, sera from individuals recently boosted with an mRNA vaccine had a minimal reduction in neutralization capacity compared to Delta
Increasing rates of breakthrough infections in South Africa and the UK confirming suspicions of decreased vaccine effectiveness of primary vaccine series, early data shows that mRNA boosters increase levels of protection, though still lower than protection against other variants
Vaccination protection against severe disease appears to still be quite good, however severe disease/death are lagging indicators and a definitive conclusion cannot be made at this time
Most therapeutic monoclonal antibodies currently approved by FDA and in use do not neutralize Omicron, however therapies targeting the host immune response are anticipated to retain effectiveness
Badea, A; Reeder, B; Groot, G; Miller, L. What is the epidemiology of the Omicron variant and its impact on health care? 2021 Dec 22, Document no.: EOC211220 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 10 p. (CEST rapid review report).
December 20, 2021
- Delta dominance - Delta remains the predominant variant accounting for most of variants sequenced from surveillance data from Public Health Ontario, Public Health England and ECDC as of the 6th of December; this is rapidly changing.
- Expect opinions from PHAC indicate that Omicron will likely outpace Delta and drive infections up to 26,600 a day by mid-January in Canada.
- ECDC projects Omicron could cause over half of all SARS-CoV-2 infections in the EU/EEA within the next few months, with probability of further introduction and community spread and impact of the spread assessed HIGH and VERY HIGH respectively.
- Preliminary evidence suggests that the various mutations in Omicron may increase transmissibility and replication; increase evasion of antibody neutralization by COVID-19 infection, vaccine-based, or monoclonal-based antibodies; increase the binding affinity of the virus to the ACE2 receptors on host cells; and may be associated with increased infectivity.
- Evidence is still emerging on the disease severity with omicron compared to Delta, however the first Omicron death has been reported in the UK during the week of December 13, 2021.
- The Delta sub-lineage AY.4.2 (Delta plus) continues account for an increasing proportion of Delta cases in the UK, with cases detected in Canada.
December 6, 2021
- A new SARS-CoV-2 variant designated Omicron has emerged and classified as a VOC by WHO. The heavily mutated variant (50 mutations -- 32 of them on the spike protein) was first identified in South Africa and has already spread to many parts of the world.
- Preliminary evidence suggests there may be an increased risk of reinfection with Omicron, however, there is still emerging evidence of the transmissibility, severity of disease, effectiveness of vaccines, and the effectiveness of current tests and treatment.
- Delta dominance - Delta remains the predominant variant accounting for most of variants sequenced from surveillance data from Public Health Ontario, Public Health England and ECDC.
- The Delta sub-lineage AY.4.2 (Delta plus) continues account for an increasing proportion of Delta cases in the UK.
- Delta variant sub-lineage AY.25 and AY.27 have been detected in Canada, with majority of the cases identified in Saskatchewan, followed by Alberta and B.C. However, experts say there’s no data to determine if these sub-lineages will be more transmissible than its parent strain.
Asamoah, G; Badea, A; Lee, S; Shumilak, G; Reeder, B; Groot, G; Muhajarine, N; Hernandez-Ronquillo L; Miller, L; Howell-Spooner, B. What is the epidemiology of variants and what are the implications for healthcare? 2021 Dec 20. Document no.: EOC031801v019 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 50 p. (CEST rapid review report).
In October, WHO released a consensus definition of post COVID-19 condition that includes 12 domains. This development should lead to better standardization of reporting and contribute to more precise prevalence estimates and better understanding of associated risk factors.
The effects of Variants of Concern (VoC) and COVID vaccination on progression of Long COVID symptoms remains unclear.
Risk factors for developing Long COVID symptoms were similar but limited evidence suggests that pre-pandemic psychological distress and poor general health were associated with developing persistent symptoms. Evidence is too limited to determine whether vaccination reduces the risk of developing Long COVID among persons with breakthrough infections.
Given the protean manifestations of Long COVID symptoms, the underlying causes are likely multifactorial; however, strong evidence to substantiate the theories of causation remains limited.
Research related to longer-term consequences of SARS CoV-2 infections in pediatric populations is growing but remains limited.
March 15, 2021
There is a lack of consensus around the clinical definition of Long COVID which in turn causes challenges with understanding the incidence and prevalence as well as the potential impact for the health care system
Information about the natural history of Long COVID is incomplete but limited evidence suggests that the immune response trajectories differ for those with few or no symptoms compared to those with severe disease. Individuals with severe disease are more likely to exhibit immunological marker abnormalities but anyone can experience functional limitations.
The mechanisms underlying the development of persistent symptoms in Long COVID remain an enigma. Despite multiple theories, there is little empirical evidence for specific immunological and or biochemical abnormalities in samples of individuals with symptoms consistent with Long COVID.
Risk factors for Long COVID include female gender, older age, higher body mass index, pre-existing asthma and the number of symptoms.
Few studies explored the short-term impact of Long COVID on health care utilization patterns and found a higher impact for those with severe disease compared with mild disease.
Williams-Roberts, H; Groot, G; Mueller, M; Dalidowicz, M. Long COVID: What does it mean for the healthcare system and programs? 2021 Oct 29. Document no.: EOC021901v2 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 14 p. (CEST rapid review report).
Consequences of delayed surgeries have potential patient-level and system-level consequences
Modelling indicates that even complete resumption of services requires additional resources to clear the backlogs caused by service disruptions
Retrospective data analysis indicates that minor delays for most cancer surgeries does not negatively impact patients, however the length of time to safely delay is largely dependent on condition and urgency
Badea, A; Groot, G; Young, C; Mueller, M. What have been the consequences of delayed surgeries due to the COVID-19 pandemic? 2021 Oct 18. Document no.: EOC210903 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 14 p. (CEST rapid review report).