Table 1.
Characteristics of the studied population stratified by index case and household members.
| Characteristics | Index cases | Household contacts |
|---|---|---|
| Age | ||
| 0–12 years | 30/304 (10%) | 148/719 (21%) |
| 13–24 years | 53/304 (17%) | 125/719 (17%) |
| 25–39 years | 75/304 (25%) | 163/719 (23%) |
| 40–59 years | 80/304 (26%) | 171/719 (24%) |
| ≥ 60 years | 66/304 (22%) | 112/719 (16%) |
| Sex | ||
| Male | 141/304 (46%) | 315/719 (44%) |
| Female | 163/304 (54%) | 404/719 (56%) |
| Obesity | ||
| Yes | 36/304 (12%) | 41/719 (6%) |
| No | 268/304 (88%) | 678/719 (94%) |
| Care for index case | ||
| Yes | — | 274/719 (38%) |
| No | — | 359/719 (50%) |
| NAa | — | 86/719 (12%) |
| Sharing bedroom with index case (2 weeks post index diagnosis) | ||
| Yes | — | 191/719 (27%) |
| No | — | 525/719 (73%) |
| NAa | — | 3/719 (3%) |
| Hours (per day) with index case outside bedroom (2 weeks post index diagnosis) | ||
| <1 h | — | 236/719 (33%) |
| >1 h | — | 473/719 (66%) |
| NAa | — | 10/719 (1%) |
| Index case mask wearing frequencyb (2 weeks post index diagnosis) | ||
| >half of the time | — | 189/719 (26%) |
| ≤half of the time | — | 322/719 (45%) |
| NAa | — | 208/719 (29%) |
| Household contact mask wearing frequencyb (2 weeks post index diagnosis) | ||
| > half of the time | — | 184/719 (25%) |
| ≤ half of the time | — | 349/719 (49%) |
| NAa | — | 186/719 (26%) |
| Vaccination status | ||
| Unvaccinated | 296/304 (97%) | 649/719 (90%) |
| 1st dosec | 5/304 (2%) | 29/719 (4%) |
| 2nd dosec | 3/304 (1%) | 41/719 (6%) |
All information except vaccination status was self-reported based on questionnaires.
aNA denotes missing data.
bHere we looked at the mask wearing frequency of index case and household contact when they were interacting with each other under the household setting.
cSARS-CoV-2 vaccine administered in Costa Rica was Comirnaty (BNT162b2).