Table 1.
Comparison between the microscopic and PCR based detection of Plasmodium falciparum from asymptomatic infections from highland and lowland sites in Western Kenya.
| Microscopic method | PCR method | ||||||
|---|---|---|---|---|---|---|---|
| No. positive | Mean density | Sensitivity | Specificity | No. positive | |||
| Region | Site | Samples tested | (%) | (range)1 | (95% CI)2 | (95% CI)2 | (%) |
| Lowland | Chemelil | 102 | 18 (17.7) | 233.8 (80–640) | 0.32 (0.18–0.51) | 0.88 (0.79–0.94) | 28 (27.5) |
| Miwani | 92 | 12 (13.0) | 388.7 (40–10280) | 0.25 (0.14–0.41) | 0.95 (0.85–0.98) | 36 (39.1) | |
| Kisian | 105 | 30 (28.6) | 471.8 (80–7200) | 0.40 (0.29–0.52) | 0.92 (0.79–0.97) | 68 (64.8) | |
| Highland | Iguhu06 | 84 | 8 (9.5) | 329.1 (120–1000) | 0.17 (0.08–0.33) | 0.96 (0.86–0.99) | 35 (41.7) |
| Iguhu07 | 216 | 3 (1.4) | 134.5 (40–760) | 0 (0–0.22) | 0.99 (0.896–1.00) | 14 (6.5) | |
1
Geometric mean intensity of P. falciparum is calculated only for microscopic-positive infections, and is expressed as the number infected red blood cells per µl blood.
2
95% CI refers to 95% confidence interval.