Table 1. Results of the EQA for the molecular detection of DENV.
| Samples no. | |||||||||||||||
| #2 | #9 | #12 | #4 | #14 | #5 | #13 | #6 | #10 | #11 | #3 | #7 | ||||
| DENV-1 | DENV-1 | DENV-1 | DENV-1 | DENV-1 | DENV-3 | DENV-3 | DENV-2 | DENV-4 | JE/YF WN/TBE | CHIK | Negative | ||||
| Copy no. [GE/mL] | |||||||||||||||
| Lab. no. | RT-PCR technique | 7,0E+05 | 7,0E+04 | 7,5E+03 | 7,0E+02 | 7,0E+01 | 3,0E+04 | 3,0E+03 | 1,0E+05 | 1,0E+05 | neg. | neg. | neg. | Score* | Classification # |
| 8 | Heminested[17] | ++ | ++ | ++ | + + | ++ | ++ | ++ | ++ | ++ | − | − | − | 22 | OPTIMAL |
| 7 | TaqMan[12] | ++ | ++ | ++ | ++ | (−) | ++ | ++ | ++ | ++ | − | − | − | 22 | OPTIMAL |
| 13 | SYBR-Green[18] | ++ | ++ | ++ | ++ | (−) | ++ | ++ | ++ | ++ | − | − | − | 22 | OPTIMAL |
| 17a | TaqMan[14] | ++ | ++ | ++ | ++ | (−) | ++ | ++ | ++ | ++ | − | − | − | 22 | OPTIMAL |
| 12 | TaqMan[19] | ++ | ++ | ++ | + | ++ | + | (−) | ++ | ++ | − | − | − | 20 | IMPROVE |
| 21 | SYBR-Greena | ++ | ++ | ++ | ++ | (−) | ++ | ++ | ++ | ++ | (+) | − | − | 20 | IMPROVE |
| 2a | Nested[12] | ++ | ++ | ++ | (−) | (−) | ++ | ++ | ++ | ++ | − | − | − | 20 | OPTIMAL |
| 2b | TaqMana | ++ | ++ | ++ | (−) | (−) | ++ | (−) | ++ | ++ | − | − | − | 18 | IMPROVE |
| 4b | Nested[28] | ++ | ++ | ++ | (−) | (−) | ++ | (−) | ++ | ++ | − | − | − | 18 | IMPROVE |
| 28a | Nestedb | ++ | ++ | ++ | (−) | (−) | ++ | (−) | ++ | ++ | − | − | − | 18 | IMPROVE |
| 15 | TaqMan[20] | ++ | ++ | (−) | (−) | ++ | ++ | (−) | ++ | ++ | − | − | − | 18 | IMPROVE |
| 5 | TaqMan[21] | ++ | ++ | ++ | ++ | (−) | (−) | (−) | ++ | ++ | − | − | − | 18 | IMPROVE |
| 20 | TaqMan[21] | ++ | ++ | ++ | ++ | (−) | (−) | (−) | ++ | ++ | − | − | − | 18 | IMPROVE |
| 14 | Nested[12] | + | + | + | + | (−) | ++ | ++ | ++ | + | − | − | − | 17 | ACCEPTABLE |
| 27 | Nestedb | + | ++ | ++ | ++ | (−) | ++ | (−) | ++ | ++ | (+) | − | − | 17 | IMPROVE |
| 28b | TaqMana | ++ | ++ | (−) | (−) | (−) | ++ | (−) | ++ | ++ | − | − | − | 16 | IMPROVE |
| 29 | TaqMan[18] | ++ | ++ | ++ | (−) | (−) | ++ | (−) | ++ | (−) | − | − | − | 16 | IMPROVE |
| 31 | TaqMana | + | + | + | + | + | + | + | + | + | − | − | − | 15 | ACCEPTABLE |
| 23b | TaqMana | + | + | (−) | (−) | (−) | ++ | (−) | ++ | ++ | − | − | − | 14 | IMPROVE |
| 19a | Nested[14] | ++ | ++ | (−) | (−) | (−) | ++ | (−) | (−) | ++ | − | − | − | 14 | IMPROVE |
| 1 | TaqManc | ++ | ++ | (−) | (−) | (−) | + | + | ++ | (−) | − | − | − | 14 | IMPROVE |
| 36 | Nested[28] | + | + | + | (−) | (−) | + | + | + | + | − | − | − | 13 | ACCEPTABLE |
| 10 | TaqMan[17] | + | + | + | (−) | (−) | + | + | + | + | − | − | − | 13 | ACCEPTABLE |
| 19b | TaqMan[19] | + | + | + | (−) | + | + | + | + | (−) | − | − | − | 13 | IMPROVE |
| 25b | Nested[15] | ++ | + | (−) | (−) | (−) | ++ | (−) | ++ | (−) | − | − | − | 12 | IMPROVE |
| 9a | Nestedb | ++ | ++ | ++ | (−) | (−) | ++ | ++ | ++ | (−) | (+) | − | − | 12 | IMPROVE |
| 9b | TaqMana | + | + | + | + | (−) | + | + | + | + | (+) | − | − | 12 | IMPROVE |
| 22 | TaqMan[13] | ++ | ++ | (−) | (−) | (−) | (−) | (−) | (−) | ++ | − | − | − | 12 | IMPROVE |
| 4a | TaqMana | + | + | + | (−) | (−) | + | (−) | + | + | − | − | − | 12 | IMPROVE |
| 30 | Nested[28] | (−) | ++ | (−) | ++ | ++ | (−) | (−) | + | (−) | − | (+) | − | 11 | IMPROVE |
| 17b | TaqMan[19] | + | + | (−) | (−) | + | (−) | + | (−) | (−) | − | − | − | 11 | IMPROVE |
| 37 | TaqMan[22] | + | + | (−) | (−) | (−) | + | + | + | (−) | − | − | − | 11 | IMPROVE |
| 3 | SYBR-Greena | + | (−) | (−) | (−) | (−) | + | (−) | + | + | − | − | − | 10 | IMPROVE |
| 16 | TaqManc | ++ | + | (−) | ++ | + | + | + | + | + | (+) | (+) | (+) | 10 | IMPROVE |
| 18 | TaqMan[19] | + | + | (−) | (−) | (−) | (−) | (−) | + | + | − | − | − | 10 | IMPROVE |
| 24 | RT-PCRb | + | + | (−) | (−) | (−) | (−) | (−) | + | + | − | − | − | 10 | IMPROVE |
| 6 | TaqManc | + | + | (−) | (−) | (−) | + | (−) | + | (−) | − | − | − | 10 | IMPROVE |
| 25a | TaqMan[19] | + | + | (−) | (−) | (−) | + | (−) | + | + | − | − | − | 10 | IMPROVE |
| 11 | Nested[15] | ++ | ++ | (−) | (−) | (−) | + | (−) | + | (−) | (+) | − | − | 10 | IMPROVE |
| 35a | Nested[12] | ++ | ++ | (−) | (−) | (−) | (−) | (−) | (−) | (−) | − | − | − | 10 | IMPROVE |
| 34 | TaqMan[23] | + | + | (−) | (−) | (−) | (−) | (−) | (−) | + | − | − | − | 9 | IMPROVE |
| 23a | SYBR-Green[29] | + | (−) | (−) | (−) | (−) | (−) | (−) | + | (−) | − | − | − | 8 | IMPROVE |
| 32 | Heminested[17] | ++ | (−) | (−) | (−) | (−) | (−) | (−) | (−) | (−) | − | − | − | 8 | IMPROVE |
| 33 | TaqMan[19] | + | + | + | (−) | (−) | (−) | (−) | + | + | − | − | − | 8 | IMPROVE |
| 26 | Nestedb | (−) | (−) | (−) | (−) | (−) | (−) | (−) | (−) | (−) | − | − | − | 6 | IMPROVE |
| 35b | Nested[16] | (−) | (−) | (−) | (−) | (−) | (−) | (−) | (−) | + | − | − | (+) | 5 | IMPROVE |
| Correct positive/total results (%) | 43/46 (93.5) | 41/46 (89) | 23/46 (50) | 14/46 (30.4) | 8/46 (17.4) | 32/46 (69.5) | 17/46 (37) | 38/46 (82.6) | 32/46 (69.5) | 40/46 (87) | 44/46 (95.6) | 44/46 (95.6) | |||
*The score reflects the quality of the diagnostic results: ++, positive result and correctly typed (score 2 points); +, positive but no information on serotype or incorrectly typed (score 1 point); (+), false positive (score 0 points); −, correct negative result (score 2 points); (−), false negative (score 0 points). Sample #14 was not evaluated for scoring.
# Classification reflects the capability to perform optimal surveillance and diagnosis activities (sensitivity up to 103 GE/ml and serotyping); acceptability for diagnosis purposes (sensitivity up to 103 GE/ml); or the need of improvement (failure to detect one or more serotypes or sensitivity below 103 GE/ml). Samples #4 and #14 were not evaluated for classification.
a In-house qRT-PCR system(s) for quantification and/or serotyping;
b In-house RT-PCR system(s);
c Commercial Artus Light Cycler test (Qiagen).