The recent wave of COVID-19 in China peaked in late December of 2022, with 0.07 million deaths confirmed in hospitals between December 16, 2022 and January 19, 2023.Integrative Biolog

Du, Zhanwei

Meyers, Lauren Ancel

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                               Zhanwei Du and Lauren Ancel Meyers           February 3, 2023 The University of Texas at Austin COVID-19 Modeling Consortium utpandemics@austin.utexas.edu  Estimated COVID-19 Mortality in China, December16, 2022 - January 19, 2023Zhanwei Du, University of Hong KongLauren Ancel Meyers, University of Texas at AustinReported COVID-19 Mortality –– Chinese CDCThe recent wave of COVID-19 in China peaked in late December of 2022, with 0.07 milliondeaths confirmed in hospitals between December 16, 2022 and January 19, 2023 1.Extreme bounds on COVID-19 MortalityFirst, we bound the estimates by considering two extreme scenarios for vaccine efficacy inChina. We estimate the total number of COVID deaths and provide a plausible range for thenumber that would be reported by the Chinese CDC, given China’s strict exclusion ofCOVID-related deaths that list other causes of deaths. The CrI’s reflect uncertainty inage-specific IFR’s 2.● If vaccine effectiveness against mortality is zero○ 5.28 (95% CrI: 4.20, 6.13) million total deaths○ Range of reported deaths: 0.23 - 2.27 million● If 100% of cases are vaccinated and vaccine effectiveness against mortality is 98.1%:○ 0.10 (95% CrI: 0.08, 0.12) million total deaths○ Range of reported deaths: 0.004 - 0.043 millionEstimated COVID-19 mortalityUsing a simulation method that incorporates data on vaccine coverage, vaccination timing,vaccine efficacy and waning of protection in different age groups, we estimate:● Total deaths: 1.46 (95% CrI: 1.17, 1.69) million● Range of reported deaths: 0.064 - 0.627 millionDu & Meyers 1 February 2023Simulation-based method for estimating COVID-19 mortality in ChinaWe run 100 simulations each with 1,000,000 individuals assigned ages according to the nationalage distribution in China. Each simulation produces an estimated number of COVID-19 deathsbetween December 16, 2022 and January 19, 2023, as described below. We report the 2.5thpercentile (lower CI bound), median, and 97.5th percentile (upper CI bound) values across the100 simulations.To estimate a plausible range of reported deaths, we multiply the lower bound by 5.5% 7 and theupper bound by 37% 9, corresponding to low and high estimates for the fraction of COVID-19death reports that do not include other causes of death.The full parameter specification is given in Table A. In each simulation, we do the following:● For each age group a, select a random IFR (IFRa) from the estimated distributions givenin Table A and assign each individual their age-specific IFR. (For each age group, drawfrom triangle distributions with lower bound, mode and upper bound equal to thecorresponding lower CI, mean, and upper CI, respectively.)● Assign each individual a random infection time, based on the time series of reportedSARS-CoV-2 test positivity in China 1.● Administer doses to each individual according to reported daily age-specific vaccinationrates in China 4:○ Randomly select the date of the first dose (t1) based on the estimated first-doserate, C1a(t).■ For children 3-11 years old, first doses begin November 1, 2021.■ For children 12-17 years old, first doses begin August 1, 2021.■ For children 18-59 years old, first doses begin December 1, 2020.■ For adults over 60 years old, first doses begin April 1, 2021.○ Randomly select the date of the second dose (t2) based on the estimatedsecond-dose rate, C2a(t), beginning 3 weeks after their first dose.○ Randomly select the date of the booster dose (t3) for adults over 18 years oldbased on the estimated booster rate, C3a(t), starting at the CDC-recommendedtime waiting period after their second dose (i.e., 6 months before December 4,2022, and 3 months after December 5, 2022).● Determine VE for each individual based on the date of their last dose. Assume thatvaccine-acquired protection begins two weeks after each dose is administered and thatprotection wanes stepwise six months following each dose 4.● For each individual, determine whether they die from COVID based on their IFR and VE.Du & Meyers 2 February 2023● Assuming that 90.36% of the Chinese population was infected during this period 1, wescale deaths in simulated population to all of China (by age group)Table A. Model Parameters and Data Sources.Symbol Description Values SourcesNaAge-specificpopulation size inChinaAge 0-9: 168127944Age 10-19: 157940134Age 20-29: 166789007Age 30-39: 223158122Age 40-49: 207180217Age 50-59: 222565082Age 60-69: 147388498Age 70-79: 80828885Age ≥ 80: 35800835China StatisticalYearbook 2021 5rProportion of deathsthat have no otherconditions/causes ofdeath reportedexcept COVID-195.5% - 37%Range based on threeestimates for theproportion of deathsattributed to COVID-19without underlyingconditions or othercauses of death:● 5.5% of reported USdeaths in 2020 7● 28.5% of reporteddeaths in Australiaduring the Omicronwave 8● 37% of deaths in 7French hospitals 9Itot(t)Proportion of thepopulation newlyinfected at time tDaily positive rate betweenDecember 16, 2022 toJanuary 19, 2023, shown inFigure A belowExtracted from Figure1-5 in Ref. 1Cia(t)Age-specific vaccinecoverage of the i-thdose (first, second,and booster) fromDecember 2020 toSeptember 2022 inChinaSee Figure B below.We assume thecumulative vaccinationrates of the first,second, and boosterdoses before March 1,2022 follows thepublished values in Ref.4.For adults < 60 years,cumulative vaccinationDu & Meyers 3 February 2023coverage hardlychanges between Marchand December of 2022.For adults ≥ 60 years,cumulative vaccinationrates for first, second,and booster doses arereported as 90.68%,86.42%, and 68.8%,respectively, as ofNovember 28, 2022 10,and 96%, 96%, and92%  as of January 20,2023 1.We assume a constantdaily rate of vaccineadministration duringthis period.VE(j,t)Vaccineeffectiveness (VE)against mortality foran individual withmost recent dose oftype j administeredat time t, as ofDecember 2022 inChinaFirst dose: after two weeks53.0%; after six months53.0%Second dose: after twoweeks 66.3%; after sixmonths 59.7%Booster dose: after twoweeks 79.2%; after sixmonths 76.3%Ref. 4VEextremeVaccineeffectiveness (VE)against mortality intwo extremescenarios —maximimum andminimum protectionmaximum: entire populationwith VE of 98.1%minimum: entire populationwith VE of 0%maximum; Ref. 4assumes VE of boostersafter six months can beas high as 98.1%.minimum: Ref. 11suggests vaccines givenover eight months agohave minimal efficacy.IFRaAge-specificinfection-fatality(IFR) withoutvaccination orantiviral treatmentAge 0-9: 0.0005% (95% CI:0.0004%, 0.0008%)Age 10-19: 0.0005% (95%CI: 0.0003%, 0.0008%)Age 20-29: 0.0005% (95%CI: 0.0004%, 0.0008%)Age 30-39: 0.023% (95%CI: 0.016%, 0.034%)Mean values are basedon estimates in Ref. 3.95% confidence intervalsare derived from Ref. 2which estimatesage-specific IFR’s at 10year intervals (ages 5,Du & Meyers 4 February 2023Age 40-49: 0.023% (95%CI: 0.016%, 0.036%)Age 50-59: 0.126% (95%CI: 0.088%, 0.196%)Age 60-69: 0.126% (95%CI: 0.087%, 0.198%)Age 70-79: 2.00% (95% CI:1.38%, 3.15%)Age ≥ 80: 8.70% (95% CI:6.12%, 13.01%)15, 25 …) between April15, 2020 and January 1,2021, prior to broadvaccination and theemergence of the Deltaand Omicron variants.Specifically, we use theratios of the lower andupper CI’s to the mean inRef. 2 to scale theestimates in Ref. 3. Forexample, consider the70-79 age group. Theestimate of4.84% (95% CI: 3.33%,7.63%) given in Ref. 2 for75 year olds yields ratiosof 0.69 to 1.58. We usethese values to scale themean for 70-79 year oldsin Ref. 3 to obtain 2.00%(95% CI: 1.38%, 3.15%).Du & Meyers 5 February 2023FiguresFigure A. Graph reproduced from a Chineses CDC report published on January 26, 2023entitled COVID-19 Clinical and Surveillance Data — December 9, 2022 to January 23,2023, China1. The reported trends are based on (1) infection surveillance –– community-basedmonitoring of nucleic acid and antigen testing and sentinel community surveillance of nucleicacid and antigen testing; (2) clinical visits and hospitalizations –– daily COVID-19 visits to allfever clinics; mild to severe COVID-19 infections and COVID-19 fatalities in all hospitals, andoutpatient clinics (emergency) COVID-19 visits in sentinel hospitals; (3) molecular surveillance(sequencing) of samples from sentinel hospitals.Du & Meyers 6 February 2023Figure B. Graph reproduced from Ref. 4 estimating age-specific uptake of primary andbooster doses in China.References1. Chinese Center for Disease Control and Prevention. COVID- 19 Clinical and SurveillanceData--Dec 9, 2022 to Jan 23, 2023, China. chinacdchttps://en.chinacdc.cn/news/latest/202301/t20230126_263523.html (2023).2. COVID-19 Forecasting Team. Variation in the COVID-19 infection-fatality ratio by age, time,and geography during the pre-vaccine era: a systematic analysis. Lancet 399, 1469–1488Du & Meyers 7 February 2023(2022).3. Leung, K., Leung, G. M. & Wu, J. Modelling the adjustment of COVID-19 response and exitfrom dynamic zero-COVID in China. bioRxiv (2022) doi:10.1101/2022.12.14.22283460.4. Cai, J. et al. Modeling transmission of SARS-CoV-2 Omicron in China. Nat. Med. 28,1468–1475 (2022).5. National Bureau of Statistics of China. China Statistical Yearbook 2021. stats.gov.cnhttp://www.stats.gov.cn/tjsj/ndsj/2021/indexch.htm.6. Adjei, S. et al. Mortality Risk Among Patients Hospitalized Primarily for COVID-19 Duringthe Omicron and Delta Variant Pandemic Periods - United States, April 2020-June 2022.MMWR Morb. Mortal. Wkly. Rep. 71, 1182–1189 (2022).7. Gundlapalli, A. V. et al. Death Certificate-Based ICD-10 Diagnosis Codes for COVID-19Mortality Surveillance - United States, January-December 2020. MMWR Morb. Mortal.Wkly. Rep. 70, 523–527 (2021).8. COVID-19 Mortality by wave. Australian Bureau of Statisticshttps://www.abs.gov.au/articles/covid-19-mortality-wave (2022).9. de Roquetaillade, C. et al. Timing and causes of death in severe COVID-19 patients. Crit.Care 25, 224 (2021).10. National Health Commission. Transcript of Press Conference of the State Council’s JointPrevention and Control Mechanism for the Novel Coronavirus Pneumonia Outbreak(November 29, 2022). http://www.nhc.gov.cn/http://www.nhc.gov.cn/xcs/s3574/202211/6fedb556a9324cd3b5b986446ee7ca34.shtml(2022).11. Leung, K., Lau, E. H. Y., Wong, C. K. H., Leung, G. M. & Wu, J. T. Estimating thetransmission dynamics of SARS-CoV-2 Omicron BF.7 in Beijing after the adjustment ofzero-COVID policy in November - December 2022. Nat. Med. (2023)doi:10.1038/s41591-023-02212-y.Du & Meyers 8 February 2023

Estimated COVID-19 Mortality in China, December 16, 2022-January 19, 2023

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Estimated COVID-19 Mortality in China, December 16, 2022-January 19, 2023

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