Time Trend in SARS-CoV-2 Seropositivity, Surveillance Detection- and Infection Fatality Ratio until Spring 2021 in the Tirschenreuth County—Results from a Population-Based Longitudinal Study in Germany
Abstract
:1. Introduction
2. Materials and Methods
2.1. Cohort Design, Inclusion Criteria, and Study Program
2.2. Data on Registered COVID-19 Related Deaths, Registered Infected, and Tirschenreuth County Inhabitants
2.3. Observation Periods
2.4. Assessment of Educational Status, Comorbidities, Self-Reported Previous Infections, and Vaccination Status
2.5. Blood Sampling, Transport and Antibody Measurements
2.6. Statistical Analysis
2.7. Standardization
2.8. Confidence and Credibility Intervals
2.9. Vaccination
3. Results
3.1. Participant Characteristics and Dropout Analysis
3.2. Crude N-Antibody Seropositivity over Time
3.3. Serology vs. Positive PCR (Self-Reported and Confirmed by Health Authorities) across the Observation Periods
3.4. Dynamics of Standardized N-Antibody Seropositivity across the Observation Periods
3.5. Development of SDR and IFR across the Observation Periods
3.6. Contribution of Senior Care Homes to Overall N-Antibody Seropositivity, SDR and IFR across the Observation Periods
3.7. Vaccination
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Variable | BL [Participants] | FU_1 [Participants] | FU_2 [Participants] |
---|---|---|---|
Age median (min, max, IQR) | 52.0 (14.0, 102.0, 35.0–64.0) [n = 4181] | 53.0 (14.0, 102.0, 37.0–64.0) [n = 3513] | 53.0 (14.0, 102.0, 37.0–64.0) [n = 3374] |
Age 14–20 % (n) | 5.4 (225) [n = 4181] | 5.0 (176) [n = 3513] | 5.2 (177) [n = 3374] |
Age 20–49 % (n) | 40.8 (1707) [n = 4181] | 38.3 (1345) [n = 3513] | 38.1 (1284) [n = 3374] |
Age 50–69 % (n) | 38.8 (1624) [n = 4181] | 41.2 (1449) [n = 3513] | 41.2 (1389) [n = 3374] |
Age 70+ % (n) | 14.9 (625) [n = 4181] | 15.5 (543) [n = 3513] | 15.5 (524) [n = 3374] |
Female % (n) | 51.6 (2158) [n = 4181] | 53.0 (1861) [n = 3513] | 53.7 (1813) [n = 3374] |
BMI median (min, max, IQR) | 26.6 (13.9, 62.1, 23.7–30.4) [n = 4134] | 26.6 (13.9, 62.1, 23.7–30.3) [n = 3474] | 26.6 (13.9, 62.1, 23.7–30.4) [n = 3339] |
Disease 1 | |||
autoimmune % (n) | 7.1 (289) [n = 4081] | 7.3 (250) [n = 3435] | 7.4 (243) [n = 3300] |
cancer % (n) | 4.9 (202) [n = 4081] | 5.2 (178) [n = 3435] | 5.0 (164) [n = 3300] |
diabetes % (n) | 7.6 (312) [n = 4081] | 7.5 (259) [n = 3435] | 7.4 (245) [n = 3300] |
cardiovascular % (n) | 9.9 (402) [n = 4081] | 9.6 (331) [n = 3435] | 9.5 (314) [n = 3300] |
none 4 % (n) | 75.8 (3093) [n = 4081] | 75.6 (2596) [n = 3435] | 76.0 (2507) [n = 3300] |
Education | |||
Years 2 median (min, max, IQR) | 11.0 (6.0, 22.0, 10.0–14.0) [n = 4085] | 11.0 (6.0, 22.0, 10.0–13.0) [n = 3433] | 11.0 (6.0, 22.0, 10.0–14.0) [n = 3301] |
High 3 % (n) | 30.0 (1225) [n = 4085] | 29.5 (1013) [n = 3433] | 29.8 (985) [n = 3301] |
antibody status | |||
N-antibody positive at BL % (n) | 8.9 (374) [n = 4181] | 10.0 (351) [n = 3513] | 10.3 (349) [n = 3374] |
Time of Analysis Sex | AnalyzableParticipants 1 n | Total N Antibody Positive % (n) 2 | Analyzable Participants n Previously Pos/Neg | Newly N Antibody Positive % (n) 3 | Newly N Antibody Negative % (n) 4 | Ever Seropositive (%) 5 | Total N Antibody Positives (%) 5 |
---|---|---|---|---|---|---|---|
Baseline | 4181 | 8.95 (374) | 0/4181 | 8.95 (374) | (n/a) | ||
women | 2158 | 9.08 (196) | 0/2158 | 9.08 (196) | (n/a) | ||
men | 2023 | 8.80 (178) | 0/2023 | 8.8 (178) | (n/a) | ||
FU1 | 3513 | 10.22 (359) | 351/3162 | 0.66 (21) | 3.70 (13) | 9.55 | 9.22 |
women | 1861 | 10.26 (191) | 187/1674 | 0.66 (11) | 3.74 (7) | 9.54 | 9.21 |
men | 1652 | 10.17 (168) | 164/1488 | 0.67 (10) | 3.66 (6) | 9.58 | 9.23 |
FU2 | 3177 | 15.68 (498) | 349/2828 | 5.80 (164) | 4.30 (15) | 14.80 | 14.09 |
women | 1710 | 15.56 (266) | 186/1524 | 5.91 (90) | 5.38 (10) | 14.89 | 14.08 |
men | 1467 | 15.81 (232) | 163/1304 | 5.67 (74) | 3.07 (5) | 14.69 | 14.10 |
Timepoint | # Confirmed Positive Registered PCR Test (# Total Self-Reported PCR Tests) | N-Antibody Negative # (%[Group]; %[All Tests]) | N-Antibody Positive # (%[Group]; %[All Tests]) |
---|---|---|---|
Until BL 12/2019–4/2020 | n = 66 (n = 501) | 4 (6.06; 0.80) | 62 (93.94; 12.38) |
between BL and FU1 6/2020–11/2020 | n = 19 (n = 1064) | 6 (31.58; 0.56) | 13 (68.4; 1.22) |
between FU1 and FU2 11/2020–4/2021 | n = 153 (n = 1568) | 8 (5.23; 0.51) | 145 (94.77; 9.25) |
until FU2 12/2019–4/2021 | n = 238 (n = 3133) | 18 (7.56; 0.57) | 220 (92.44; 7.02) |
Vaccination 1- and Serostatus | N + S | Only S | S | S |
---|---|---|---|---|
Antibody Positive | Antibody Positive | Seropositive | Antibody Negative | |
% (#) | % (#) | % (#) | % (#) | |
Not vaccinated, | 20.17 (375) | 1.61 (30) | 21.79 (405) | 78.21 (1454) |
n = 1859 | ||||
vaccinated (all), | 9.18 (137) | 63.47 (947) | 72.65 (1084) | 27.35 (408) |
n = 1492 | ||||
1× vaccinated (<14 d), | 8.48 (38) | 14.73 (66) | 23.21 (104) | 76.79 (344) |
n = 448 | ||||
1× vaccinated (>14 d), | 10.69 (76) | 81.43 (579) | 92.12 (655) | 7.88 (56) |
n = 711 | ||||
2× vaccinated (<14 d), | 25 (2) | 75 (6) | 100 (8) | 0 (0) |
n = 8 | ||||
2× vaccinated (>14 d), | 6.21 (19) | 93.46 (286) | 99.67 (305) | 0.33 (1) |
n = 306 | ||||
No of vaccinations unknown | 10.5 (2) | 52.6 (10) | 63.2 (12) | 36.8 (7) |
n = 19 |
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Einhauser, S.; Peterhoff, D.; Beileke, S.; Günther, F.; Niller, H.-H.; Steininger, P.; Knöll, A.; Korn, K.; Berr, M.; Schütz, A.; et al. Time Trend in SARS-CoV-2 Seropositivity, Surveillance Detection- and Infection Fatality Ratio until Spring 2021 in the Tirschenreuth County—Results from a Population-Based Longitudinal Study in Germany. Viruses 2022, 14, 1168. https://doi.org/10.3390/v14061168
Einhauser S, Peterhoff D, Beileke S, Günther F, Niller H-H, Steininger P, Knöll A, Korn K, Berr M, Schütz A, et al. Time Trend in SARS-CoV-2 Seropositivity, Surveillance Detection- and Infection Fatality Ratio until Spring 2021 in the Tirschenreuth County—Results from a Population-Based Longitudinal Study in Germany. Viruses. 2022; 14(6):1168. https://doi.org/10.3390/v14061168
Chicago/Turabian StyleEinhauser, Sebastian, David Peterhoff, Stephanie Beileke, Felix Günther, Hans-Helmut Niller, Philipp Steininger, Antje Knöll, Klaus Korn, Melanie Berr, Anja Schütz, and et al. 2022. "Time Trend in SARS-CoV-2 Seropositivity, Surveillance Detection- and Infection Fatality Ratio until Spring 2021 in the Tirschenreuth County—Results from a Population-Based Longitudinal Study in Germany" Viruses 14, no. 6: 1168. https://doi.org/10.3390/v14061168
APA StyleEinhauser, S., Peterhoff, D., Beileke, S., Günther, F., Niller, H. -H., Steininger, P., Knöll, A., Korn, K., Berr, M., Schütz, A., Wiegrebe, S., Stark, K. J., Gessner, A., Burkhardt, R., Kabesch, M., Schedl, H., Küchenhoff, H., Pfahlberg, A. B., Heid, I. M., ... Wagner, R. (2022). Time Trend in SARS-CoV-2 Seropositivity, Surveillance Detection- and Infection Fatality Ratio until Spring 2021 in the Tirschenreuth County—Results from a Population-Based Longitudinal Study in Germany. Viruses, 14(6), 1168. https://doi.org/10.3390/v14061168