Prevalence of SARS-CoV-2 infection by close contacts and symptoms
| Number of participants | Crude prevalence % (95% CI) | Adjusted prevalence* % (95% CI) | Prevalence ratio (95% CI) | ||
| Overall | 23 762 | 3.4 (3.2 to 3.7) | 3.4 (3.2 to 3.6) | ||
| Contact with a COVID case | |||||
| No contact | 17 402 | 2.3 (2.1 to 2.5) | 2.6 (2.3 to 2.8) | Ref | |
| Occupational contact | 3372 | 5.0 (4.3 to 5.8) | 3.6 (3.1 to 4.2) | 1.42 (1.18 to 1.71) | |
| Household contact | 2483 | 7.9 (6.9 to 9.0) | 7.0 (6.1 to 8.0) | 2.75 (2.32 to 3.25) | |
| Both | 505 | 9.9 (7.6 to 12.8) | 7.3 (5.4 to 9.3) | 2.87 (2.15 to 3.83) | |
| Symptoms (previous 2 weeks) | |||||
| No | 11 897 | 2.9 (2.6 to 3.2) | 3.2 (2.9 to 3.6) | Ref | |
| Yes | 11 865 | 4.0 (3.6 to 4.3) | 3.6 (3.3 to 3.9) | 1.11 (0.97 to 1.28) | |
| Symptoms at recruitment | |||||
| No | 17 755 | 3.1 (2.9 to 3.4) | 3.2 (2.9 to 3.4) | Ref | |
| Yes | 6007 | 4.3 (3.9 to 4.9) | 4.1 (3.6 to 4.5) | 1.28 (1.11 to 1.48) | |
| Shortness of breath | |||||
| No | 22 320 | 3.3 (3.0 to 3.5) | 3.4 (3.1 to 3.6R) | Ref | |
| Yes, previous 2 weeks | 919 | 6.1 (4.7 to 7.8) | 4.2 (3.1 to 5.3) | 1.26 (0.96 to 1.66) | |
| Yes, at recruitment | 523 | 5.2 (3.6 to 7.4) | 4.1 (2.6 to 5.6) | 1.22 (0.83 to 1.77) | |
| Fever (>37.7°C) | |||||
| No | 23 322 | 3.2 (3.0 to 3.5) | 3.3 (3.1 to 3.6) | Ref | |
| Yes, previous 2 weeks | 417 | 11.8 (9.0 to 15.2) | 5.2 (3.7 to 6.8) | 1.57 (1.15 to 2.13) | |
| Yes, at recruitment | 23 | 21.7 (9.4 to 42.8) | 9.1 (0.9 to 17.2) | 2.71 (1.10 to 6.73) | |
| Low fever | |||||
| No | 22 225 | 3.2 (2.9 to 3.4) | 3.3 (3.1 to 3.5) | Ref | |
| Yes, previous 2 weeks | 1325 | 6.8 (5.6 to 8.3) | 4.2 (3.3 to 5.0) | 1.26 (1.01 to 1.58) | |
| Yes, at recruitment | 212 | 9.4 (6.2 to 14.2) | 7.0 (4.0 to 10.0) | 2.12 (1.38 to 3.26) | |
| Dry and persistent cough | |||||
| No | 22 142 | 3.1 (2.9 to 3.3) | 3.2 (3.0 to 3.5) | Ref | |
| Yes, previous 2 weeks | 954 | 8.3 (6.7 to 10.2) | 4.8 (3.7 to 5.8) | 1.48 (1.16 to 1.88) | |
| Yes, at recruitment | 666 | 7.7 (5.9 to 9.9) | 6.0 (4.4 to 7.6) | 1.88 (1.43 to 2.48) | |
| Runny nose | |||||
| No | 18 877 | 3.4 (3.1 to 3.6) | 3.4 (3.2 to 3.7) | Ref | |
| Yes, previous 2 weeks | 2411 | 3.8 (3.1 to 4.7) | 3.3 (2.6 to 4.0) | 0.96 (0.78 to 1.19) | |
| Yes, at recruitment | 2474 | 3.5 (2.8 to 4.3) | 3.5 (2.8 to 4.2) | 1.03 (0.83 to 1.28) | |
| Sore throat | |||||
| No | 21 225 | 3.3 (3.0 to 3.5) | 3.4 (3.2 to 3.7) | Ref | |
| Yes, previous 2 weeks | 1806 | 4.4 (3.6 to 5.5) | 3.0 (2.4 to 3.7) | 0.88 (0.70 to 1.11) | |
| Yes, at recruitment | 731 | 5.3 (3.9 to 7.2) | 4.5 (3.1 to 5.9) | 1.32 (0.96 to 1.80) | |
| Headache | |||||
| No | 18 135 | 3.2 (3.0 to 3.5) | 3.4 (3.1 to 3.7) | Ref | |
| Yes, previous 2 weeks | 4482 | 3.6 (3.1 to 4.2) | 3.1 (2.6 to 3.5) | 0.9 (0.76 to 1.07) | |
| Yes, at recruitment | 1145 | 5.6 (4.4 to 7.1) | 5.1 (3.9 to 6.3) | 1.49 (1.16 to 1.92) | |
| Anosmia/ageusia | |||||
| No | 22 735 | 2.7 (2.5 to 2.9) | 2.8 (2.5 to 3.0) | Ref | |
| Yes, previous 2 weeks | 607 | 20.3 (17.3 to 23.7) | 13.3 (11.0 to 15.6) | 4.82 (3.98 to 5.84) | |
| Yes, at recruitment | 420 | 18.6 (15.1 to 22.6) | 13.5 (10.6 to 16.3) | 4.87 (3.88 to 6.12) | |
| Severe tiredness | |||||
| No | 19 124 | 3.0 (2.8 to 3.3) | 3.2 (2.9 to 3.4) | Ref | |
| Yes, previous 2 weeks | 2559 | 5.0 (4.3 to 6.0) | 3.9 (3.2 to 4.6) | 1.23 (1.01 to 1.48) | |
| Yes, at recruitment | 2079 | 5.0 (4.1 to 6.0) | 4.7 (3.8 to 5.6) | 1.49 (1.21 to 1.82) | |
| General discomfort | |||||
| No | 21 827 | 3.0 (2.8 to 3.2) | 3.1 (2.9 to 3.4) | Ref | |
| Yes, previous 2 weeks | 1393 | 8.3 (6.9 to 9.8) | 5.2 (4.2 to 6.2) | 1.66 (1.35 to 2.03) | |
| Yes, at recruitment | 542 | 7.9 (5.9 to 10.5) | 6.2 (4.4 to 8.0) | 1.97 (1.46 to 2.66) | |
| Unusual back pain | |||||
| No | 21 737 | 3.2 (3.0 to 3.4) | 3.3 (3.0 to 3.5) | Ref | |
| Yes, previous 2 weeks | 1047 | 7.6 (6.1 to 9.3) | 5.1 (4.0 to 6.2) | 1.55 (1.23 to 1.95) | |
| Yes, at recruitment | 978 | 4.2 (3.1 to 5.6) | 3.8 (2.6 to 4.9) | 1.14 (0.84 to 1.55) | |
| Muscle pain | |||||
| No | 20 734 | 3.1 (2.9 to 3.3) | 3.2 (3.0 to 3.5) | Ref | |
| Yes, previous 2 weeks | 1622 | 7.0 (5.9 to 8.4) | 4.8 (3.9 to 5.7) | 1.5 (1.23 to 1.83) | |
| Yes, at recruitment | 1406 | 4.2 (3.3 to 5.4) | 4.1 (3.1 to 5.1) | 1.26 (0.98 to 1.64) | |
| Vomiting, nausea | |||||
| No | 23 162 | 3.4 (3.2 to 3.6) | 3.4 (3.2 to 3.6) | Ref | |
| Yes, previous 2 weeks | 484 | 4.1 (2.7 to 6.3) | 3.1 (1.7 to 4.4) | 0.9 (0.58 to 1.40) | |
| Yes, at recruitment | 116 | 5.2 (2.3 to 11.0) | 5.5 (1.3 to 9.7) | 1.61 (0.75 to 3.44) | |
| Diarrhoea | |||||
| No | 21 748 | 3.3 (3.1 to 3.6) | 3.4 (3.2 to 3.7) | Ref | |
| Yes, previous 2 weeks | 1654 | 4.2 (3.4 to 5.3) | 3.3 (2.5 to 4.0) | 0.96 (0.75 to 1.22) | |
| Yes, at recruitment | 360 | 5.3 (3.4 to 8.1) | 4.6 (2.6 to 6.6) | 1.36 (0.87 to 2.11) | |
| Emergency room visits | |||||
| No | 22 804 | 3.1 (2.9 to 3.4) | 3.2 (3.0 to 3.4) | Ref | |
| Yes | 811 | 11.2 (9.2 to 13.6) | 8.6 (6.9 to 10.4) | 2.72 (2.21 to 3.36) | |
| Hospitalisation | |||||
| No | 23 454 | 3.3 (3.1 to 3.6) | 3.3 (3.1 to 3.6) | Ref | |
| Yes | 223 | 13.9 (10.0 to 19.1) | 12.2 (8.3 to 16.1) | 3.66 (2.64 to 5.08) | |
*Adjusted by age, gender, occupation, epidemiological week, and laboratory.