Volume 26, Number 11—November 2020
Research
Case-Control Study of Use of Personal Protective Measures and Risk for SARS-CoV 2 Infection, Thailand
Pawinee Doung-ngern, Rapeepong Suphanchaimat, Apinya Panjangampatthana, Chawisar Janekrongtham, Duangrat Ruampoom, Nawaporn Daochaeng, Napatchakorn Eungkanit, Nichakul Pisitpayat, Nuengruethai Srisong, Oiythip Yasopa, Patchanee Plernprom, Pitiphon Promduangsi, Panita Kumphon, Paphanij Suangtho, Peeriya Watakulsin, Sarinya Chaiya, Somkid Kripattanapong, Thanawadee Chantian, Emily Bloss, Chawetsan Namwat, and Direk Limmathurotsakul
Table 1
Factors associated with coronavirus disease among persons followed through contract tracing, Thailand, March–April 2020*
| Factors | COVID-19 cases, no. (%), N = 211† | Controls, no. (%), N = 839† | Crude odds ratio (95% CI)‡ | p value | Adjusted odds ratio (95% CI)‡ | p value |
|---|---|---|---|---|---|---|
| Sex | n = 211 | n = 838 | ||||
| F | 65 (30.8) | 404 (48.2) | Referent | 0.52 | Referent | 0.37 |
| M |
146 (69.2) |
434 (51.8) |
0.83 (0.47–1.46) |
0.76 (0.41–1.41) |
||
| Age group, y | n =211 | n = 829 | ||||
| <15 | 6 (2.8) | 49 (5.9) | 0.65 (0.17–2.48) | 0.29 | 0.57 (0.15–2.21) | 0.21 |
| >15–40 | 94 (44.5) | 435 (52.5) | Referent | Referent | ||
| >40–65 | 98 (46.4) | 302 (36.4) | 1.65 (0.91–2.97) | 1.77 (0.94–3.32) | ||
| >65 |
13 (6.2) |
43 (5.0) |
1.29 (0.33–5.07) |
0.97 (0.22–4.24) |
||
| Contact place§ | n = 211 | n = 839 | ||||
| Nightclub | 35 (16.6) | 193 (23.0) | NA | NA | NA | NA |
| Boxing stadium | 125 (59.2) | 19 (2.3) | ||||
| Workplace | 11 (5.2) | 286 (34.0) | ||||
| Household | 38 (18.0) | 192 (22.9) | ||||
| Others |
2 (0.9) |
149 (17.8) |
||||
| Shortest distance of contact | n = 197 | n = 809 | ||||
| Physical contact | 132 (67.0) | 292 (36.1) | Referent | 0.001 | Referent | 0.02 |
| <1 m without physical contact | 61 (30.9) | 335 (41.4) | 0.76 (0.43–1.35) | 1.09 (0.58–2.07) | ||
| >1 m |
4 (2.0) |
182 (22.5) |
0.08 (0.02–0.31) |
0.15 (0.04–0.63) |
||
| Duration of contact within 1 m | n = 199 | n = 801 | ||||
| >60 min | 180 (90.4) | 487 (60.8) | Referent | 0.003 | Referent | 0.09 |
| >15–60 min | 14 (7.0) | 162 (20.2) | 0.53 (0.24–1.17) | 0.67 (0.29–1.55) | ||
| <15 min |
5 (2.5) |
152 (19.0) |
0.13 (0.04–0.46) |
0.24 (0.07–0.90) |
||
| Sharing dishes or cups¶ | n = 210 | n = 837 | ||||
| N | 125 (59.5) | 576 (68.8) | Referent | 0.001 | Referent | 0.39 |
| Y |
85 (40.5) |
261 (31.2) |
2.71 (1.48–4.94) |
1.33 (0.70–2.54) |
||
| Sharing cigarettes# | n = 209 | n = 836 | ||||
| N | 196 (93.8) | 824 (98.6) | Referent | 0.001 | Referent | 0.03 |
| Y |
13 (6.2) |
12 (1.4) |
6.12 (2.12–17.72) |
3.47 (1.09–11.02) |
||
| Handwashing** | n = 210 | n = 826 | ||||
| None | 44 (20.9) | 121 (14.6) | Referent | <0.001 | Referent | 0.045 |
| Sometimes | 114 (54.3) | 333 (40.3) | 0.41 (0.18–0.91) | 0.34 (0.14–0.81) | ||
| Often |
52 (24.8) |
372 (45.0) |
0.19 (0.08–0.46) |
0.33 (0.13–0.87) |
||
| Type of mask†† | n = 211 | n = 834 | ||||
| None | 102 (48.3) | 500 (60.0) | Referent | 0.003 | – | – |
| Nonmedical masks only | 25 (11.8) | 77 (9.2) | 0.78 (0.32–1.90) | |||
| Nonmedical and medical | 12 (5.7) | 48 (5.8) | 0.46 (0.13–1.64) | |||
| Medical mask only |
72 (34.1) |
209 (25.0) |
0.25 (0.12–0.53) |
|||
| Compliance with mask-wearing†† | n = 210 | n = 823 | ||||
| Not wearing a mask | 102 (48.6) | 500 (60.7) | Referent | <0.001 | Referent | 0.006 |
| Wearing a mask sometimes | 79 (37.6) | 125 (15.2) | 0.75 (0.37–1.52) | 0.87 (0.41–1.84) | ||
| Always wearing a mask |
29 (13.8) |
198 (24.1) |
0.16 (0.07–0.36) |
0.23 (0.09–0.60) |
||
| *NA, not applicable; COVID-19, coronavirus disease. †Data not available for all cases and controls for all factors. ‡Crude and adjusted odds ratios were estimated using logistic regression with random effects for location and for index patient nested within the same location. §The state enterprise office was included as a workplace. Others included restaurants, markets, malls, religious places, and households of index patients or other persons by persons not living in that household. Location was included in the model as a random effect variable. ¶Sharing multiserving dishes and using communal serving utensils to portion food individually was not categorized as sharing dishes. #Included sharing electronic cigarettes and any vaping devices. **Included washing with soap and water, and by using alcohol-based solutions. ††Wearing masks incorrectly, such as not covering both nose and mouth, was considered the same as not wearing a mask for analyses. Crude odds ratios of wearing mask and of each factor evaluated were estimated using logistic regression with random effects for location and for index patient nested within the same location to take into account clustering; therefore, the crude odds ratios are not equal to dividing of the odds in the case group by the odds in the control group. | ||||||
Page created: September 02, 2020
Page updated: October 17, 2020
Page reviewed: October 17, 2020
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