TABLE 1.
Comparison of PCR versus microscopic detection of Cryptosporidium
| Method | No. of samples examined | No. of positives detected | Sensitivity (%)a | Specificity (%)b | Strain discrimination |
|---|---|---|---|---|---|
| PCR | 511 | 36c | 100 | 100 | Yesc |
| Microscopy | 511 | 29 | 83.7 | 98.9 | No |
a
Calculated as follows: [number of true positives/(number of true positives + number of false negatives)] × 100.
b
Calculated as follows: [number of true negatives/(number of true negatives + number of false positives)] × 100.
c
The PCR test was able not only to detect Cryptosporidium oocysts but also to identify isolate genotypes (15). Of the 36 positives detected in the present study, 30 were of the human genotype and 6 were of the calf genotype.