TABLE 2. Sensitivity* for detecting evidence of infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV), by selected characteristics of 84 laboratories — seven African countries, 2017.
| Characteristic | Assay target virus (no. of laboratories†)
Mean % (95% CI) |
p-value§ | ||
|---|---|---|---|---|
| HIV (n = 84) | HBV (n = 81) | HCV (n = 79) | ||
|
Overall, unadjusted
|
96.6 (95.0–98.1)
|
75.8 (70.8–81.2)
|
80.2 (74.7–86.2)
|
—
|
|
Country
¶
| ||||
| Ghana |
93.5 (87.8–96.6) |
58.5 (52.9–63.8) |
70.9 (50.8–85.2) |
<0.001 |
| Kenya |
99.0 (93.8–99.9) |
93.3 (84.2–97.4) |
96.0 (89.3–98.6) |
|
| Malawi |
98.7 (92.0–99.8) |
60.6 (47.4–72.4) |
60.0 (43.2–74.7) |
|
| Mozambique |
98.7 (91.9–99.8) |
54.7 (42.1–66.8) |
94.0 (85.1–97.7) |
|
| Nigeria |
98.5 (94.7–99.6) |
82.5 (69.6–90.7) |
78.8 (61.6–89.6) |
|
| Rwanda |
100 |
100 |
100 |
|
| Tanzania |
90.5 (83.1–94.8) |
84.3 (69.6–92.7) |
75.4 (63.4–84.4) |
|
|
Assay type
| ||||
| Rapid |
95.0 (91.9–96.9) |
59.8 (54.7–64.6) |
70.5 (61.1–78.4) |
<0.001 |
| EIA-3 |
97.7 (84.7–99.7) |
98.0 (91.4–99.6) |
96.9 (92.2–98.8) |
|
| EIA-4 |
99.0 (96.8–99.7) |
(Not used) |
84.4 (74.3–91.0) |
|
|
NBTS
| ||||
| No |
95.5 (92.8–97.3) |
66.2 (60.2–71.7) |
73.8 (64.7–81.2) |
<0.001 |
| Yes |
98.5 (95.8–99.5) |
93.0 (83.4–97.3) |
91.8 (86.7–95.0) |
|
|
Blood units tested per year** | ||||
| 1,000 |
96.6 (94.7–97.8) |
75.3 (69.8–80.2) |
79.5 (72.9–84.8) |
0.006 |
| 3,162 |
97.1 (95.3–98.3) |
79.3 (73.6–84.1) |
82.0 (75.6–87.1) |
|
| 10,000 |
97.6 (95.7–98.7) |
82.8 (76.6–87.6) |
84.3 (77.5–89.4) |
|
|
Components produced per year** | ||||
| None |
95.5 (92.4–97.4) |
73.3 (65.9–79.5) |
74.4 (65.1–82.0) |
0.026 |
| 1,000 blood units |
97.6 (95.4–98.7) |
78.8 (71.3–84.4) |
85.2 (78.3–90.1) |
|
| 10,000 blood units |
98.0 (95.4–99.2) |
80.5 (70.7–87.6) |
87.8 (79.9–92.9) |
|
|
Percentage of donors who are volunteers
| ||||
| 1–24 |
96.2 (92.8–98.0) |
69.3 (61.7–75.9) |
69.8 (57.8–79.6) |
0.013 |
| 25–74 |
94.4 (88.9–97.3) |
64.2 (51.4–75.2) |
89.2 (79.3–94.6) |
|
| 75–100 |
98.2 (94.3–99.4) |
89.8 (81.0–94.8) |
85.3 (76.0–91.4) |
|
|
No. of laboratory personnel
| ||||
| 1–6 |
97.6 (95.4–98.8) |
74.7 (66.0–81.8) |
81.7 (73.2–87.9) |
0.36 |
| 7–54 | 95.3 (91.7–97.4) | 77.9 (70.7–83.7) | 78.1 (67.7–85.9) | |
Abbreviations: CI = confidence interval; EIA-3 = third generation enzyme immunoassay; EIA-4 = fourth generation enzyme immunoassay; NBTS = national blood transfusion service.
* Based on univariate models.
† Because HBV- and HCV-positive specimens were not assayed by three and five laboratories, respectively, sensitivity evaluations for assay targets HIV, HBV, and HCV were based on 84, 81, and 79 laboratories, respectively.
§ P-values report statistical significance of associations of sensitivity with the interaction between assay virus and laboratory characteristics.
¶ Model excluded Rwanda and excluded the interaction term. P-value reports statistical significance of association of sensitivity with country.
** Characteristic was analyzed on the log-10 scale. Mean sensitivity was estimated at the values shown.