TY - JOUR
T1 - Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection Fatality Rate Among Elderly Danes
T2 - A Cross-sectional Study on Retired Blood Donors
AU - Pedersen, Ole Birger
AU - Nissen, Janna
AU - Dinh, Khoa Manh
AU - Schwinn, Michael
AU - Kaspersen, Kathrine Agergård
AU - Boldsen, Jens Kjærgaard
AU - Didriksen, Maria
AU - Dowsett, Joseph
AU - Sørensen, Erik
AU - Thørner, Lise Wegner
AU - Larsen, Margit Anita Hørup
AU - Grum-Schwensen, Birgitte
AU - Sækmose, Susanne
AU - Paulsen, Isabella Worlewenut
AU - Frisk, Nanna Lond Skov
AU - Brodersen, Thorsten
AU - Vestergaard, Lasse Skafte
AU - Rostgaard, Klaus
AU - Mølbak, Kåre
AU - Skov, Robert Leo
AU - Erikstrup, Christian
AU - Ullum, Henrik
AU - Hjalgrim, Henrik
N1 - © The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America.
PY - 2021/11/2
Y1 - 2021/11/2
N2 - BACKGROUND: Although the vast majority of individuals succumbing to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are elderly, infection fatality rate (IFR) estimates for the age group ≥70 years are still scarce. To this end, we assessed SARS-CoV-2 seroprevalence among retired blood donors and combined it with national coronavirus disease 2019 (COVID-19) survey data to provide reliable population-based IFR estimates for this age group.METHODS: We identified 60 926 retired blood donors aged ≥70 years in the rosters of 3 regionwide Danish blood banks and invited them to fill in a questionnaire on COVID-19-related symptoms and behaviors. Among 24 861 (40.8%) responders, we invited a random sample of 3200 individuals for blood testing. Overall, 1201 (37.5%) individuals were tested for SARS-CoV-2 antibodies (Wantai) and compared with 1110 active blood donors aged 17-69 years. Seroprevalence 95% confidence intervals (CIs) were adjusted for assay sensitivity and specificity.RESULTS: Among retired (aged ≥70 years) and active (aged 17-69 years) blood donors, adjusted seroprevalences were 1.4% (95% CI, .3-2.5%) and 2.5% (95% CI, 1.3-3.8%), respectively. Using available population data on COVID-19-related fatalities, IFRs for patients aged ≥70 years and for 17-69 years were estimated at 5.4% (95% CI, 2.7-6.4%) and .083% (95% CI, .054-.18%), respectively. Only 52.4% of SARS-CoV-2-seropositive retired blood donors reported having been sick since the start of the pandemic.CONCLUSIONS: COVID-19 IFR in the age group >69 years is estimated to be 65 times the IFR for people aged 18-69 years.
AB - BACKGROUND: Although the vast majority of individuals succumbing to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are elderly, infection fatality rate (IFR) estimates for the age group ≥70 years are still scarce. To this end, we assessed SARS-CoV-2 seroprevalence among retired blood donors and combined it with national coronavirus disease 2019 (COVID-19) survey data to provide reliable population-based IFR estimates for this age group.METHODS: We identified 60 926 retired blood donors aged ≥70 years in the rosters of 3 regionwide Danish blood banks and invited them to fill in a questionnaire on COVID-19-related symptoms and behaviors. Among 24 861 (40.8%) responders, we invited a random sample of 3200 individuals for blood testing. Overall, 1201 (37.5%) individuals were tested for SARS-CoV-2 antibodies (Wantai) and compared with 1110 active blood donors aged 17-69 years. Seroprevalence 95% confidence intervals (CIs) were adjusted for assay sensitivity and specificity.RESULTS: Among retired (aged ≥70 years) and active (aged 17-69 years) blood donors, adjusted seroprevalences were 1.4% (95% CI, .3-2.5%) and 2.5% (95% CI, 1.3-3.8%), respectively. Using available population data on COVID-19-related fatalities, IFRs for patients aged ≥70 years and for 17-69 years were estimated at 5.4% (95% CI, 2.7-6.4%) and .083% (95% CI, .054-.18%), respectively. Only 52.4% of SARS-CoV-2-seropositive retired blood donors reported having been sick since the start of the pandemic.CONCLUSIONS: COVID-19 IFR in the age group >69 years is estimated to be 65 times the IFR for people aged 18-69 years.
KW - Aged
KW - Antibodies, Viral
KW - Blood Donors
KW - COVID-19
KW - Cross-Sectional Studies
KW - Denmark
KW - Humans
KW - SARS-CoV-2
KW - Seroepidemiologic Studies
UR - http://www.scopus.com/inward/record.url?scp=85120613959&partnerID=8YFLogxK
U2 - 10.1093/cid/ciaa1627
DO - 10.1093/cid/ciaa1627
M3 - Journal article
C2 - 33103182
VL - 73
SP - e2962-e2969
JO - Clinical Infectious Diseases
JF - Clinical Infectious Diseases
SN - 1058-4838
IS - 9
ER -