Table 6.
Serology and association with mortality
| Test | N (%) | Relative risk | P value | ||
|---|---|---|---|---|---|
| Total | Deaths | RR (95% CI) | |||
| EIA IgM | Positive | 22/83 (26) | 2/22 (9) | Reference | < 0.001 |
| Equivocal | 14/83 (17) | 0/14 (0) | NA | ||
| Negative | 47/83 (57) | 18/47 (38) | 1.5 (1.2–1.9) | ||
| EIA IgG | Positive | 62/114 (54) | 8/62 (13) | Reference | < 0.001 |
| Equivocal | 9/114 (8) | 1/9 (11) | N/A | ||
| Negative | 43/114 (38) | 17/43 (40) | 1.4 (1.1–1.9) | ||
| IHA | Positive | 50/114 (44) | 3/50 (6) | Reference | < 0.001 |
| Borderline | 17/114 (15) | 7/17 (41) | N/A | ||
| Negative | 47/114 (41) | 15/47 (32) | 1.4 (1.2–1.7) | ||
EIA = enzyme immunoassay; IHA = indirect hemagglutination assay; NA = not applicable.