Table 3.
Adjusted seroprevalence estimates according to site, sociodemographic and clinical variables, Blood Donors Services, Cameroon, 2021
| Survey 1 | Survey 2 | Survey 3 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Positive tests | Age–sex-standardized seroprevalence (95% CI) | Adjusted seroprevalence (95% CrI) | p value | Positive tests | Age–sex-standardized seroprevalence (95% CI) | Adjusted seroprevalence (95% CrI) | p value | Positive tests | Age–sex-standardized seroprevalence (95% CI) | Adjusted seroprevalence (95% CI) | p value | |
| Overall | 475/742 | 64.0% (60.3–69.7) | 66.3% (61.1–71.3) | 1004/1201 | 84.7% (82.2–87.3) | 87.2% (84.0–90.0) | 1425/1500 | 95.3% (94.0–96.7) | 98.4% (96.8–99.7) | |||
| Study site | 0.001 | < 0.001 | 0.6 | |||||||||
| CHY | 251/404 | 59.5% (52.8–65.9) | 60.6% (53.6–67.5) | 417/519 | 81.2% (76.3–85.3) | 83.5% (78.8–87.9) | 648/725 | 95.4% (93.5–96.7) | 98.2% (96.0–99.8) | |||
| JHY | 97/167 | 62.2% (51.9–71.5) | 62.7% (51.4–73.4) | 280/341 | 82.9% (77.7–87.1) | 84.7% (77.9–90.7) | 343/364 | 93.9% (90.1–96.3) | 96.9% (92.6–99.7) | |||
| HLD | 127/171 | 78.9% (71.1–85.1) | 81.0% (72.4–88.7) | 307/341 | 92.4% (88.9–94.9) | 94.8% (90.2–98.5) | 398/411 | 96.2% (91.6–98.3) | 98.5% (95.8–99.9) | |||
| Gender | 0.7 | 0.3 | 0.2 | |||||||||
| Male | 428/671 | 64.1% (60.0–68.1) | 65.4% (59.3–71.3) | 907/1088 | 83.5% (80.9–85.9) | 86.0% (82.3–89.5) | 1280/1351 | 94.5% (92.9–95.8) | 97.6% (95.5–99.4) | |||
| Female | 47/71 | 66.8% (53.6–77.8) | 68.6% (59.9–77.0) | 97/113 | 87.5% (79.4–92.7) | 90.0% (84.7–94.6) | 145/149 | 97.3% (92.1–99.1) | 99.0% (96.9–100.0) | |||
| Grouped age | 0.6 | 0.3 | 0.6 | |||||||||
| 18–34 | 361/568 | 63.9% (59.0–68.5) | 64.9% (58.1–71.5) | 773/929 | 83.3% (80.2–86.0) | 85.6% (81.3–89.5) | 1126/1183 | 95.7% (94.1–96.8) | 98.4% (96.3–99.9) | |||
| 35–55 | 114/174 | 66.2% (57.2–74.2) | 67.2% (60.0–74.2) | 231/272 | 86.5% (81.2–90.4) | 89.1% (84.8–93.0) | 299/317 | 94.9% (91.6–96.9) | 97.6% (95.0–99.7) | |||
| Marital status | 0.9 | 0.4 | 0.2 | |||||||||
| Single | 398/624 | 65.3% (60.2–70.0) | 66.6% (60.9–72.1) | 838/1003 | 84.1% (80.7–86.9) | 86.5% (83.0–89.9) | 1208/1269 | 95.9% (94.5–96.9) | 98.8% (97.1–99.9) | |||
| Married/Cohabiting | 77/118 | 64.1% (51.8–74.8) | 65.2% (55.1–74.8) | 166/198 | 86.7% (81.0–90.8) | 88.7% (82.8–93.7) | 217/231 | 93.7% (88.6–96.7) | 96.4% (92.4–99.4) | |||
| Occupation | 0.006 | 0.14 | 0.6 | |||||||||
| Student | 152/245 | 61.1% (52.2–69.4) | 62.4% (53.7–70.9) | 300/366 | 85.0% (80.6–88.6) | 87.6% (82.1–92.5) | 504/532 | 94.2% (91.1–96.3) | 97.9% (94.6–99.9) | |||
| Technician/agent | 136/225 | 58.7% (50.1–66.8) | 59.3% (48.8–69.7) | 348/425 | 79.6% (73.7–84.5) | 81.5% (74.4–87.7) | 411/437 | 95.4% (92.8–97.0) | 97.2% (93.6–99.7) | |||
| Senior | 103/162 | 63.8% (53.3–73.2) | 65.0% (54.8–74.6) | 234/270 | 86.4% (79.3–91.4) | 88.4% (82.8–93.3) | 345/358 | 95.4% (91.0–97.7) | 98.0% (95.0–99.9) | |||
| Other | 81/105 | 82.1% (72.5–88.8) | 83.4% (73.3–92.0) | 121/139 | 89.3% (82.3–93.7) | 90.9% (83.5–96.8) | 165/173 | 96.8% (93.1–98.6) | 98.0% (94.0–99.9) | |||
| Comorbidities | 0.003 | 0.3 | 0.5 | |||||||||
| None | 461/725 | 64.2% (59.3–68.8) | 65.5% (60.4–70.4) | 997/1194 | 84.6* | 8.72% (84.1–90.0) | 1413/1488 | 95.8* | 98.3% (96.6–99.7) | |||
| One or more | 14/17 | 92.2% (71.5–98.2) | 87.3% (64.2–99.3) | 7/7 | 100.0* | 83.0% (54.2–100.0) | 12/12 | 100.0* | 94.2% (82.6–100.0) | |||
| Symptoms | 0.14 | 0.087 | 0.9 | |||||||||
| None | 319/489 | 67.7% (62.2–72.8) | 69.0% (62.8–74.9) | 816/983 | 83.8% (80.5–86.6) | 86.2% (82.7–89.4) | 1102/1158 | 95.4% (93.6–96.7) | 98.4% (96.5–99.8) | |||
| One or more | 156/253 | 60.1% (51.1–68.5) | 61.3% (52.9–69.5) | 188/218 | 89.0% (83.5–92.8) | 91.5% (84.9–96.7) | 323/342 | 95.1% (91.8–97.1) | 97.9% (94.5–99.9) | |||
| Previous contact with a COVID-19 case | 0.3 | 0.3 | 0.5 | |||||||||
| No/don’t know | 471/733 | 41.0% (5.1–90.0) | 66.6% (61.5–71.4) | 984/1175 | 85.1% (82.4–87.4) | 87.5% (84.5–90.4) | 1409/1483 | 95.4% (93.8–96.5) | 98.4% (96.8–99.8) | |||
| Yes | 2/6 | 65.2% (60.4–69.8) | 50.5% (13.3–87.7) | 16/21 | 72.0% (34.0–92.8) | 75.5% (53.0–93.2) | 15/16 | 93.7%* | 85.2% (60.0–99.1) | |||
| Previously PCR COVID-19 tested | 0.2 | 0.2 | 0.3 | |||||||||
| No | 415/647 | 65.2% (60.4–69.8) | 67.5% (62.2–72.7) | 874/1044 | 84.2% (81.1–86.9) | 86.7% (83.4–89.7) | 1300/1372 | 95.1% (93.5–96.4) | 98.1% (96.4–99.6) | |||
| Yes | 60/95 | 58.0% (44.1–70.6) | 58.8% (44.8–71.9) | 130/157 | 88.3% (82.1–92.5) | 90.6% (82.9–96.8) | 125/128 | 97.6% (91.5–99.4) | 97.9% (92.8–99.9) | |||
| Outcome of previous test | 0.4 | 0.4 | 0.7 | |||||||||
| Negative | 58/94 | 57.6%* | 58.9% (45.2–72.1) | 119/144 | 89.5%* | 89.6% (81.0–96.3) | 120/123 | 98.3%* | 96.9% (90.2–99.9) | |||
| Positive | 1/1 | 100.0%* | 66.3% (20.7–100.0) | 7/7 | 100.0%* | 88.7% (68.1–100.0) | 8/8 | 100.0%* | 85.3% (59.6–100.0) | |||
| COVID-19 vaccination | 25/25 | 100.0%* | 93.5% (81.2–100.0) | |||||||||
*The survey confidence interval was not computed because the observed proportion was 100% or close to or no sufficient sample size