Table 2. Prevalence of and risk factors associated with SARS-CoV-2 positive test result among participants in survey of SARS-CoV-2 prevalence in Malawi in October 2020*.
| Characteristic | Community, N = 4,261 |
Health facility staff, N = 970 |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Pos | Weighted prevalence (95% CI) | Crude OR (95% CI) | Adjusted OR (95% CI)† | Pos | Weighted prevalence (95% CI) | Crude OR (95% CI) | Adjusted OR (95% CI)† | ||
| Overall |
423 |
7.8 (6.3–9.6) |
NA |
NA |
|
124 |
9.7 (6.4–14.5) |
NA |
NA |
| Sex | |||||||||
| M | 170 | 8.3 (6.5–10.4) | Referent | Referent | 58 | 9.7 (5.6–15.6) | Referent | Referent | |
| F |
253 |
7.5 (6.0–9.4) |
0.9 (0.7–1.1) |
0.9 (0.6–1.2) |
|
66 |
9.7 (6.1–15.1) |
1.0 (0.6–1.6) |
0.7 (0.4–1.0) |
| Age, y | |||||||||
| 10–19 | 71 | 5.3 (3.7–7.5) | Referent | Ref | 5 | 57.4 (4.4–97.5) | Ref | Referent | |
| 20–29 | 104 | 6.9 (5.3–9.0) | 1.3 (0.9–1.9) | 1.3 (0.8–2.4) | 38 | 7.6 (4.4–12.9) | 0.06 (0.01–0.3)§ | 0.1 (0.01–0.5)¶ | |
| 30–39 | 105 | 9.7 (7.4–12.6) | 1.9 (1.3–3.0)§ | 2.6 (1.3–5.2)§ | 41 | 12.6 (6.4–23.4) | 0.1 (0.02–0.4)§ | 0.2 (0.03–0.9)¶ | |
| 40–49 | 61 | 6.2 (4.0–9.5) | 1.2 (0.8–1.8) | 1.8 (0.9–3.6) | 32 | 6.6 (3.3–13.0) | 0.1 (0.01–0.3)§ | 0.1 (0.01–0.7)¶ | |
| ≥50 |
82 |
11.0 (7.6–15.8) |
2.2 (1.4–3.4)¶ |
2.8 (1.4–5.4)§ |
|
8 |
8.7 (2.6–25.4) |
0.1 (0.01–0.4)§ |
0.2 (0.02–1.2) |
| District | |||||||||
| Karonga | 103 | 9.4 (7.3–12.2) | Referent | Referent | 13 | 8.9 (2.2–29.4) | Referent | Referent | |
| Blantyre | 67 | 13.1 (9.0–18.7) | 1.4 (0.9–2.2) | 1.3 (0.9–2.1) | 25 | 4.7 (1.1–18.0) | 3.5 (0.8–15.2) | 3.6 (0.6–21.4) | |
| Lilongwe | 47 | 6.1 (3.5–10.2) | 0.6 (0.3–1.1) | 0.9 (0.6–1.6) | 23 | 10 (6.7–14.7) | 2.3 (0.6–8.6) | 2.1 (0.4–10.2) | |
| Mangochi | 38 | 4.1 (2.6–6.2) | 0.4 (0.2–0.6)§ | 0.5 (0.3–0.8)§ | 6 | 2.6 (1.0–6.6) | 0.5 (0.1–2.5) | 0.7 (0.1–3.5) | |
| Mzimba North |
168 |
12.1 (8.7–16.6) |
1.3 (0.8–2.1) |
1.5 (1.0–2.2) |
|
57 |
14.5 (6.7–28.5) |
2.0 (0.3–12.0) |
2.0 (0.4–11.3) |
| Location type | |||||||||
| Rural | 59 | 3.1 (1.8–5.5) | Referent | Referent | 27 | 7.4 (3.6–14.7) | Referent | Referent | |
| Urban |
364 |
12.6 (11.2–14.1) |
4.4 (2.5–7.9)¶ |
4.2 (2.6–6.7)¶ |
|
97 |
14.5 (9.7–21.1) |
2.1 (0.9–4.9) |
1.8 (0.7–4.9) |
| Household size | |||||||||
| 1–2 | 47 | 8.4 (5.9–11.8) | Referent | – | 33 | 8.3 (3.6–17.9) | Referent | NA | |
| 3–4 | 167 | 7.4 (5.7–9.4) | 0.9 (0.6–1.3) | NA | 35 | 8.3 (3.9–16.9) | 1.0 (0.3–3.9) | NA | |
| ≥5 |
209 |
8.0 (6.1–10.4) |
1.0 (0.6–1.5) |
NA |
|
56 |
11.6 (7.3–17.9) |
1.4 (0.6–3.5) |
NA |
| Education# | |||||||||
| No education | 22 | 7.6 (4.2–13.2) | Referent | Referent | NA | NA | NA | ||
| Primary | 151 | 5.2 (3.8–7.1) | 0.7 (0.4–1.3) | 0.4 (0.2–0.9)¶ | 3 | 5.1 (1.7–14.3) | Referent | NA | |
| Secondary | 211 | 11.9 (9.7–14.4) | 1.6 (0.9–3.1) | 0.8 (0.4–1.7) | 53 | 8.6 (5.6–13.0) | 1.7 (0.6–5.5) | NA | |
| Tertiary/postsecondary |
39 |
14.4 (10.6–19.3) |
2.1 (1.0–4.1)¶ |
0.8 (0.4–1.8) |
|
68 |
12.0 (7.1–19.7) |
2.5 (0.7–8.9) |
NA |
| Occupation | |||||||||
| Student | 81 | 6.7 (4.6–9.8) | Referent | Referent | NA | NA | NA | ||
| Unemployed | 160 | 7.7 (6.1–9.7) | 1.2 (0.8–1.7) | 0.7 (0.4–1.4) | NA | NA | NA | ||
| Employed, HFS | 13 | 4.9 (1.1–18.6) | 0.7 (0.2.3.3) | 0.2 (0.05–1.1) | NA | NA | NA | ||
| Employed, non-HFS | 3 | 10.0 (6.4–15.2) | 1.5 (0.9–2.7) | 0.6 (0.2–1.2) | NA | NA | NA | ||
| Retired | 36 | 25.7 (14.5–41.3) | 4.8 (2.1–10.9)¶ | 1.4 (0.5–4.0) | NA | NA | NA | ||
| Other |
130 |
7.6 (5.5–10.4) |
1.1 (0.7–1.8) |
0.6 (0.3–1.2) |
|
|
NA |
NA |
NA |
| Contact with confirmed case | |||||||||
| No | 422 | 7.8 (6.3–9.6) | Referent | NA | 117 | 9.5 (6.1–14.4) | Referent | NA | |
| Yes |
1 |
14.5 (0.14–95.3) |
2.0 (0.3–14.9) |
NA |
|
7 |
26.1 (8.5–57.3) |
3.4 (0.9–12.7) |
NA |
| Attended gatherings** | |||||||||
| No | 90 | 6.9 (4.8–9.8) | Referent | NA | 19 | 9.8 (6.3–15.0) | Referent | NA | |
| Yes |
333 |
8.3 (6.7–10.3) |
1.2 (0.8–1.8) |
NA |
|
105 |
9.7 (6.0–15.3) |
1.0 (0.5–2.0) |
NA |
| Any medical condition | |||||||||
| No | 367 | 7.7 (6.2–9.5) | Referent | NA | 103 | 10.1 (6.8–14.7) | Referent | NA | |
| Yes |
56 |
8.7 (5.8–13.0) |
1.1 (0.8–1.7) |
NA |
|
21 |
8.3 (3.3–19.4) |
0.8 (0.3–2.0) |
NA |
| Diabetes mellitus | |||||||||
| No | 401 | 7.5 (6.0–9.3) | Referent | Referent | 120 | 9.8 (6.2–15.3) | Referent | Referent | |
| Yes |
10 |
27.3 (12.9–48.9) |
4.6 (1.7–12.5)§ |
2.4 (0.9–6.3) |
|
2 |
17.6 (0.9–84.2) |
2.0 (0.2–16.2) |
1.9 (0.3–11.6) |
| CVD, including hypertension | |||||||||
| No | 383 | 7.6 (6.1–9.4) | Referent | NA | 113 | 10.6 (6.8–16.2) | Referent | NA | |
| Yes |
30 |
8.4 (4.6–14.9) |
1.1 (0.6–2.0) |
NA |
|
9 |
3.3 (0.65–15.5) |
0.3 (0.6–1.4) |
NA |
| Immunosuppressive condition†† | |||||||||
| No | 398 | 7.5 (6.1–9.3) | Referent | NA | 116 | 9.0 (5.7–13.9) | Referent | NA | |
| Yes |
9 |
12.0 (5.8–22.9) |
1.7 (0.7–3.8) |
NA |
|
5 |
23.1 (8.1–50.7) |
3.1 (1.7–8.7)¶ |
NA |
| Obesity | |||||||||
| No | 407 | 7.6 (6.1–9.3) | Referent | NA | 122 | 10.0 (6.3–15.5) | NA | NA | |
| Yes |
2 |
19.2 (3.3–6.2) |
2.9 (0.5–15.9) |
NA |
|
0 |
0 |
NA |
NA |
| Asthma | |||||||||
| No | 407 | 7.6 (6.1–9.3) | Referent | NA | 119 | 10.5 (6.6–16.3) | Referent | NA | |
| Yes |
2 |
9.5 (4.6–18.5) |
1.3 (0.6–2.7) |
NA |
|
3 |
1.9 (0.34–9.7) |
0.2 (0.03–0.8)¶ |
NA |
| Chronic lung disease, including COPD | NA | ||||||||
| No | 411 | 7.7 (6.2–9.4) | Referent | NA | 121 | 9.9 (6.2–15.4) | Referent | NA | |
| Yes |
1 |
9.7 (0.05–69.6) |
1.3 (0.1–12.2) |
NA |
|
1 |
59.1 (–) |
13.1 (0.7–246.7) |
NA |
| Pregnant | |||||||||
| No | 88 | 7.6 (6.0–9.6) | Referent | NA | 66 | 10.0 (6.3–15.7) | NA | NA | |
| Yes |
9 |
6.3 (2.8–13.4) |
0.8 (0.3–1.9) |
NA |
|
0 |
0 |
NA |
NA |
| Smoking | |||||||||
| No | 400 | 7.9 (6.4–9.7) | Referent | NA | 120 | 10.1 (6.6–15.1) | NA | NA | |
| Yes, current | 4 | 5.5 (0.9–26.5) | 0.7 (0.1–3.7) | NA | 0 | 0 | NA | NA | |
| Yes, past |
19 |
6.0 (3.3–10.5) |
0.7 (0.4–1.3) |
NA |
|
4 |
4.2 (0.61–24.3) |
0.4 (0.05–2.9) |
NA |
| International travel‡‡ | |||||||||
| No | 417 | 7.8 (6.3–9.6) | Referent | NA | 13 | 9.6 (6.2–14.5) | Referent | NA | |
| Yes | 5 | 12.4 (3.0–39.8) | 1.7 (0.4–6.5) | NA | 3 | 18.0 (3.7–55.7) | 2.1 (0.6–7.7) | NA | |
*COPD, chronic obstructive pulmonary disease; CVD, cardiovascular disease; HFS, health facility staff; NA, not available; OR, odds ratio; pos, positive. †Adjusted for age, sex, district and residence. ‡p value <0.05. §p value <0.01. ¶p value <0.001. #Education: primary education = 8 y; secondary education = 4 y; tertiary/postsecondary = college/university education. **Gathering included any of prayers, sporting events or market, family celebrations, weddings, funerals and bars. ††From cancer, chemotherapy, radiation therapy, immunosuppressive medications, self-reported HIV, organ transplant, or inherited immunodeficiency. ‡‡International travel includes both road and air travel.