TY - JOUR
T1 - Relative risks of COVID-19 fatality between the first and second waves of the pandemic in Ontario, Canada
AU - Hsu, Sylvia H.
AU - Chang, Su Hsin
AU - Gross, Cary P.
AU - Wang, Shi Yi
N1 - Funding Information:
Dr. Gross reported receiving research grants from the National Comprehensive Cancer Network (funded by Pfizer and AstraZeneca), funding from Johnson and Johnson to assist with developing new approaches to sharing clinical trial data (through the Yale Open Data Access Project), and funding from Flatiron, Inc., for travel/speaking, outside the submitted work. No other disclosures were reported.
Publisher Copyright:
© 2021 The Author(s)
PY - 2021/8
Y1 - 2021/8
N2 - Objectives: To examine whether the case fatality rate (CFR) of COVID-19 decreased over time and whether the COVID-19 testing rate is a driving factor for the changes if the CFR decreased. Methods: Analyzing COVID-19 cases, deaths and tests in Ontario, Canada, we compared the CFR between the first wave and the second wave across 26 public health units in Ontario. We also explored whether a high testing rate was associated with a large CFR decrease. Results: The first wave CFR ranged from 0.004 to 0.146, whereas the second wave CFR ranged from 0.003 to 0.034. The pooled RR estimate of second wave COVID-19 case fatality, compared with first wave, was 0.24 (95% CI: 0.19-0.32). Additionally, COVID-19 testing percentages were not associated with the estimated relative risk (P=0.246). Conclusions: The COVID-19 CFR decreased significantly in Ontario during the second wave, and COVID-19 testing was not a driving factor for this decrease.
AB - Objectives: To examine whether the case fatality rate (CFR) of COVID-19 decreased over time and whether the COVID-19 testing rate is a driving factor for the changes if the CFR decreased. Methods: Analyzing COVID-19 cases, deaths and tests in Ontario, Canada, we compared the CFR between the first wave and the second wave across 26 public health units in Ontario. We also explored whether a high testing rate was associated with a large CFR decrease. Results: The first wave CFR ranged from 0.004 to 0.146, whereas the second wave CFR ranged from 0.003 to 0.034. The pooled RR estimate of second wave COVID-19 case fatality, compared with first wave, was 0.24 (95% CI: 0.19-0.32). Additionally, COVID-19 testing percentages were not associated with the estimated relative risk (P=0.246). Conclusions: The COVID-19 CFR decreased significantly in Ontario during the second wave, and COVID-19 testing was not a driving factor for this decrease.
UR - http://www.scopus.com/inward/record.url?scp=85111298944&partnerID=8YFLogxK
U2 - 10.1016/j.ijid.2021.06.059
DO - 10.1016/j.ijid.2021.06.059
M3 - Article
C2 - 34216734
AN - SCOPUS:85111298944
SN - 1201-9712
VL - 109
SP - 189
EP - 191
JO - International Journal of Infectious Diseases
JF - International Journal of Infectious Diseases
ER -