Update on COVID-19 Projections Science Advisory and Modelling Consensus Tables December 16, 2021 Key findings 2 • Cases are climbing across most public health units. The Omicron variant will shortly become the dominant variant. • Omicron transmits very quickly. Early evidence suggests it can produce severe disease. Without prompt intervention, ICU occupancy could reach unsustainable levels in early January. • Although vaccines are less effective against Omicron infection, boosters can substantially increase protection. Even 2 doses likely provide strong protection against severe illness. The risk of severe illness is dramatically higher in the unvaccinated. • We can help protect the most vulnerable with vaccination (children and boosters). Rapid rollout of booster doses is essential, with strong focus on the most vulnerable (e.g. long-term care, shelters, high￾risk communities) and healthcare workers. • Increasing vaccination is not enough to slow this wave. Circuit breakers with strong additional public health measures (at least 50% fewer contacts) and strong booster campaigns (250,000 per day) could blunt the Omicron wave. High-quality masks, physical distancing indoors, improved ventilation, and increased access to rapid testing can help buy time for boosters to take effect and keep schools open. • Although uncertainty persists, waiting for more information will eliminate the opportunity for action. Rising cases, ICU occupancy, and deaths in European peer jurisdictions show potential risk The Ontario Stringency Index (41) is similar to UK (47) and Denmark (44); the Netherlands are at 56, Australia, France and Germany are at ≥67. Ontario vaccine coverage (77% of population fully vaccinated) similar to Netherlands and Australia (~75%) and Denmark (77%), and higher than remaining peer countries (~69%). Data: https://data.ontario.ca/ and https://ourworldindata.org/explorers/coronavirus-data-explorer Analysis: Secretariat of the Science Advisory Table 3 In Ontario, cases are increasing in most public health units Data: CCM Data note: Data for the most recent day have been censored to account for reporting delays Analysis: Ontario Health 14-day increases 14-day decreases 0 20 40 60 80 100 120 140 160 180 200 220 Weekly new cases per 100,000 residents KFLA Sudbury Windsor-Essex Chatham-Kent Simcoe Muskoka Hastings & PEC Southwestern Brant Thunder Bay Wellington-Dufferin-Guelph Niagara Lambton Middlesex-London Waterloo Huron Perth Leeds Grenville Lanark Hamilton Halton Ottawa Renfrew Durham York Toronto Peel Peterborough Grey Bruce North Bay Parry Sound Haliburton KPR Porcupine Algoma Timiskaming Haldimand-Norfolk Eastern Northwestern November 28 December 11 Average weekly cases on 4 Omicron cases are rising quickly in Ontario. Omicron will be the dominant variant this week. Data: https://data.ontario.ca 5 Analysis: Secretariat of the Science Advisory Table (https://covid19-sciencetable.ca/ontario-dashboard/) South Africa is cited as evidence of Omicron’s lower severity, but hospitalizations, ICU occupancy, and in-hospital deaths are rising despite a younger population with some immunity Median age in Gauteng 27 years (Ontario 41 years), estimated percentage infected ~90% (Ontario ~10%), estimated percentage highly immune among adults ~32% (Ontario ~15%) Analysis: Secretariat of the Science Advisory Table Data: https://www.nicd.ac.za/diseases-a-z-index/disease-index-covid-19/surveillance-reports/daily-hospital-surveillance-datcov-report/ 6 A steep rise in cases in South Africa during the current Omicron wave is followed by a steep rise in hospitalizations, while the rise in deaths currently is less steep than in previous waves 7 Median age in South Africa 28 years (Ontario 41 years), estimated percentage infected ~90% (Ontario ~10%), estimated percentage highly immune among adults ~32% (Ontario ~15%) Analysis: Secretariat of the Science Advisory Table Data: https://www.nicd.ac.za/diseases-a-z-index/disease-index-covid-19/surveillance-reports/daily-hospital-surveillance-datcov-report/ and https://ourworldindata.org/explorers/coronavirus-data-explorer Initial data from Denmark indicate that the percentage of cases requiring hospital admission is not lower with Omicron Analysis: Secretariat of the Science Advisory Table 8 Data: https://files.ssi.dk/covid19/omikron/statusrapport/rapport-omikronvarianten-13122021-i30w Omicron Other strains Cases 3,437 88,940 Hospital admissions 28 665 Percentage hospitalized 0.81% 0.75% Maintaining vaccine effectiveness against Omicron will require aggressive booster campaign UK real-world surveillance data suggests a significant reduction in vaccine effectiveness (VE) against symptomatic infection for Omicron • 2 doses of Pfizer vaccine: VE ~35% after 14 weeks • 3rd dose of Pfizer vaccine: increase VE to ~75% in the 1st month 9 Source: UK HAS https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1040076/Technical_Briefing_31.pdf Vaccine effectiveness against symptomatic diseases by period after dose 2 and dose 3 (booster) of Pfizer vaccine for Delta (black squares) and Omicron (grey circles) The Omicron variant requires new assumptions for modelling What we know Infectiousness Omicron cases double every 2-4 days (UK, Scotland, Denmark ~2 days, South Africa ~3.5 days) We estimate that each case of Omicron is infecting 6.1 times more individuals than Delta There is a high risk for a close contact of a case becoming infected (UK: adjusted odds ratio of 2.09) Omicron will be the dominant strain very quickly (consistent with data from the UK and Denmark) We modeled infectiousness consistent with Ontario, UK and Danish data Severity The severity of Omicron is unclear • Recent data from South Africa suggesting about 25% less severity cannot be extrapolated to northern high-income countries due to differences in population age and degree of immunity/previous infection • Early Danish data suggests the same severity as previous strains We modelled two options: (i) the same as Delta and (ii) 25% less than Delta Vaccine Effectiveness Vaccine effectiveness against Omicron infection is lower than with Delta for 2 doses: 34% (Pfizer, UK); 33% (South Africa) Vaccine effectiveness against Omicron infection is stronger with 3 doses: 75% (Pfizer; UK) Vaccine effectiveness against hospitalization with 2 doses is lower than with Delta but still strong: 70% (South Africa) We modelled a full range of assumptions from 25% vaccine effectiveness with 2 doses against infection through to 100% effective against infection (extreme case) We modelled vaccine effectiveness against infection with 3 doses at 70% We modelled vaccine effectiveness against hospitalization given infection from Omicron at 90% (with 2 or 3 doses) 10 With Omicron, cases are predicted to increase at a rapid pace but an immediate circuit breaker can blunt impact. Predictions informed by modeling from COVID-19 ModCollab, McMasterU, PHO, WesternU, YorkU 11 Data (Observed Cases): covid-19.ontario.ca Figure shows predictions based on a consensus across models from 5 scientific teams. • Different models use different approaches and assumptions. • All scenarios assume continuing current public health measures. • Circuit breaker scenarios are assumed to start December 15 and include additional strong public health measures (reducing contacts by at least 50%) that substantially reduce contacts and rapid roll-out of booster doses. Historic max for daily case reports No additional measures Circuit breaker on 15 Dec 0 2500 5000 7500 10000 27 Nov 04 Dec 11 Dec 18 Dec 25 Dec 01 Jan Daily cases Reported cases 7-day average Analysis: Ontario Health COVID-19 hospitalizations and ICU admissions are increasing 0 500 1,000 1,500 2,000 2,500 COVID inpatient or ICU total census Patients in ICU with COVID-related critical illness Patients in inpatient beds (incl. ICU) with active COVID19 26.6% increase in COVID inpatients, 25.8% increase in ICU census over most recent 4 weeks 12 ICU occupancy is likely to rise substantially Predictions: COVID-19 ModCollab based on case predictions in previous slide 13 Data (Observed ICU Occupancy): CCSO No additional measures Circuit breaker on 15 Dec 0 100 200 300 400 500 600 26 Nov 03 Dec 10 Dec 17 Dec 24 Dec 31 Dec ICU occupancy Observed ICU occupancy 7-day average Assumption: Omicron has same severity as Delta ICU occupancy is likely to rise even if Omicron is less severe (25%) than Delta Predictions: COVID-19 ModCollab based on case predictions in previous slide 14 Data (Observed ICU Occupancy): CCSO 0 100 200 300 400 500 600 26 Nov 03 Dec 10 Dec 17 Dec 24 Dec 31 Dec ICU occupancy Observed ICU occupancy 7-day average No additional measures Circuit breaker on 15 Dec Third dose coverage will be important to protect the vulnerable. This should be accelerated. 0% 20% 40% 60% 80% 100% Percentage with at least 1 vaccine dose Percentage with 2 doses* Percentage with 3 doses** 5-64 years Vaccine Coverage 5-64 years Individuals with any risk condition (highest-risk/high-risk/at-risk) Individuals with none of the listed conditions Recent experience with homelessness 0% 20% 40% 60% 80% 100% Percentage with at least 1 vaccine dose Percentage with 2 doses* Percentage with 3 doses** 65+ years Vaccine Coverage 65+ years Individuals with any risk condition (highest-risk/high-risk/at-risk) Individuals with none of the listed conditions Recent experience with homelessness Source: ICES 15 With prompt action we can slow down and reduce some of the impact of the Omicron wave • Circuit breakers with public health measures that cut contacts by 50% and rapid roll-out of booster doses could blunt the Omicron wave. • Accelerated boosters for the most vulnerable and healthcare workers and their families, and caregivers will help reduce transmission to vulnerable people and help protect the health workforce. • Help keep schools, workplaces and places where people gather indoors safe by reinforcing the importance of key behaviors & public health measures: • Wear a well-fitted high-quality mask • Physical distance and avoid indoor spaces where there is crowding • Increase ventilation in all indoor spaces • Increase access to rapid testing • Match distribution of therapeutics to where they are needed most to mitigate the impact of potential shortages. • Although uncertainty persists, waiting for more information will eliminate the opportunity for action. 16 Current public health measures are effective against Omicron 17 Adapted from: https://uihc.org/health-topics/why-swiss-cheese-may-be-key-keeping-you-safe-covid-19 Key findings 18 • Cases are climbing across most public health units. The Omicron variant will shortly become the dominant variant. • Omicron transmits very quickly. Early evidence suggests it can produce severe disease. Without prompt intervention, ICU occupancy could reach unsustainable levels in early January. • Although vaccines are less effective against Omicron infection, boosters can substantially increase protection. Even 2 doses likely provide strong protection against severe illness. The risk of severe illness is dramatically higher in the unvaccinated. • We can help protect the most vulnerable with vaccination (children and boosters). Rapid rollout of booster doses is essential, with strong focus on the most vulnerable (e.g. long-term care, shelters, high￾risk communities) and healthcare workers. • Increasing vaccination is not enough to slow this wave. Circuit breakers with strong additional public health measures (at least 50% fewer contacts) and strong booster campaigns (250,000 per day) could blunt the Omicron wave. High-quality masks, physical distancing indoors, improved ventilation, and increased access to rapid testing can help buy time for boosters to take effect and keep schools open. • Although uncertainty persists, waiting for more information will eliminate the opportunity for action. Contributors • COVID-19 Modeling Collaborative: Kali Barrett, Stephen Mac, David Naimark, Aysegul Erman, Yasin Khan, Raphael Ximenes, Sharmistha Mishra, Beate Sander • ICES: Jeff Kwong, Hannah Chung, Sharifa Nasreen, Siyi He, Sarah Buchan, Deshayne Fell, Maria Sundaram, Peter Austin • McMasterU: Irena Papst, Ben Bolker, Jonathan Dushoff, David Earn • Modeling Consensus Table: Isha Berry • Our Health Counts Toronto ICES COVID-19 AHRQ linkage project: Janet Smylie, Stephanie McConkey, Beth Rachlis, Lisa Avery, Graham Mercredi, Cheryllee Bourgeois, Mike Rotondi • Ontario Health: Erik Hellsten, Stephen Petersen, Anna Lambrinos • PHO: Kevin Brown, Sarah Buchan, Alyssa Parpia • Science Advisory Table: Peter Jüni, Karen Born, Sarah Baert, Kali Barrett, Pavlos Bobos, Nicolas Bodmer, Shujun Yan • Western University/London Health Sciences Centre: Lauren Cipriano, Wael Haddara • YorkU: Jianhong Wu, Michael Glazer, Zack McCarthy 19 Content and review by Modelling Consensus and Scientific Advisory Table members and secretariat Beate Sander,* Peter Jüni, Brian Schwartz,* Upton Allen, Vanessa Allen, Kali Barrett, Isha Berry, Nicolas Bodmer, Isaac Bogoch, Karen Born, Kevin Brown, Sarah Buchan, Yoojin Choi, Lauren Cipriano, Troy Day, David Earn,* Gerald Evans, Jennifer Gibson, Anna Greenberg, Anne Hayes,* Michael Hillmer, Jessica Hopkins, Jeff Kwong, Fiona Kouyoumdjian, Audrey Laporte, John Lavis, Gerald Lebovic, Brian Lewis, Linda Mah, Kamil Malikov, Doug Manuel, Roisin McElroy, Allison McGeer, Michelle Murti, John McLaughlin, Sharmistha Mishra, Andrew Morris, Samira Mubareka, Christopher Mushquash, Ayodele Odutayo, Menaka Pai, Alyssa Parpia, Samir Patel, Anna Perkhun, Bill Praamsma, Justin Presseau, Fahad Razak, Rob Reid,* Paula Rochon, Laura Rosella, Michael Schull, Arjumand Siddiqi, Chris Simpson, Arthur Slutsky, Janet Smylie, Robert Steiner, Ashleigh Tuite, Tania Watts, Ashini Weerasinghe, Scott Weese, Xiaolin Wei, Jianhong Wu, Diana Yan, Emre Yurga *Chairs of Scientific Advisory, Evidence Synthesis, and Modelling Consensus Tables For table membership and profiles, please visit the About and Partners pages on the Science Advisory Table website. 20