Table 3.
Risk factors for transmission of SARS-CoV-2
| Unadjusted odds ratio (95% CI) | p value | Adjusted odds ratio (95% CI) | p value | ||
|---|---|---|---|---|---|
| Index case | |||||
| Age, per year | 1·02 (0·99–1·05) | 0·069 | 1·01 (0·99–1·03) | 0·46 | |
| Sex | |||||
| Men | 1 (ref) | NA | 1 (ref) | NA | |
| Women | 0·74 (0·40–1·36) | 0·33 | 0·71 (0·37–1·39) | 0·32 | |
| Viral load, per log10 change | 1·27 (1·09–1·48) | 0·0020 | 1·29 (1·10–1·50) | 0·0012 | |
| Cough | 1·00 (0·55–1·82) | 0·99 | 1·13 (0·64–2·00) | 0·66 | |
| Dyspnoea | 0·80 (0·31–2·07) | 0·64 | 0·75 (0·30–1·89) | 0·55 | |
| Rhinitis | 1·46 (0·46–4·63) | 0·52 | 1·31 (0·42–4·11) | 0·64 | |
| Contact | |||||
| Age, per year | 1·03 (1·01–1·05) | 0·0085 | 1·02 (1·01–1·04) | 0·0008 | |
| Sex | |||||
| Men | 1 (ref) | NA | 1 (ref) | NA | |
| Women | 0·93 (0·58–1·49) | 0·77 | 1·33 (0·79–2·23) | 0·28 | |
| Mask use by the contact | |||||
| Never | 1 (ref) | NA | 1 (ref) | NA | |
| Always | 0·93 (0·47–1·83) | 0·84 | 1·55 (0·76–3·16) | 0·23 | |
| Unknown | 1·18 (0·59–2·36) | 0·47 | 1·49 (0·74–3·01) | 0·26 | |
| Contact type | |||||
| Health-care work | 1 (ref) | NA | 1 (ref) | NA | |
| Household | 3·07 (1·68–5·62) | 0·0003 | 3·00 (1·59–5·65) | 0·0006 | |
| Nursing home | 1·75 (0·19–16·01) | 0·62 | 1·90 (0·30–1·91) | 0·49 | |
| Other | 0·32 (0·03–3·05) | 0·32 | 1·19 (0·10–4·31) | 0·89 | |
NA=not applicable. SARS-CoV-2=severe acute respiratory syndrome coronavirus 2.