Volume 10, Number 5—May 2004
Research
Laboratory Diagnosis of SARS
Paul K.S. Chan*
, Wing-Kin To†, King-Cheung Ng*, Rebecca K. Y. Lam*, Tak-Keung Ng†, Rickjason C. W. Chan* , Alan Wu*, Wai-Cho Yu†, Nelson Lee*, David S. C. Hui*, Sik-To Lai†, Ellis K. L. Hon*, Chi-Kong Li*, Joseph J. Y. Sung*, and John S. Tam*
, Wing-Kin To†, King-Cheung Ng*, Rebecca K. Y. Lam*, Tak-Keung Ng†, Rickjason C. W. Chan* , Alan Wu*, Wai-Cho Yu†, Nelson Lee*, David S. C. Hui*, Sik-To Lai†, Ellis K. L. Hon*, Chi-Kong Li*, Joseph J. Y. Sung*, and John S. Tam*Table 2
Diagnostic yield of specimen types to detect SARS-CoV according to time of collectiona
| No. positive specimens/no. tested for SARS-CoV (%) |
|||||||
|---|---|---|---|---|---|---|---|
| RT-PCR | Virus isolation | ||||||
| Specimen type |
1 week |
2 weeks |
3–4 weeks |
1 week |
2 weeks |
3–4 weeks |
|
| Respiratory |
|||||||
| Tracheal aspirate |
1/2 (50.0) |
1/1 (100) |
4/4 (100) |
2/3 (66.7) |
1/1 (100) |
0/3 |
|
| Pooled throat and nasal swabs |
6/17 (35.3) |
2/3 (66.7) |
2/5 (40.0) |
4/18 (22.2) |
0/3 |
0/1 |
|
| Nasal swab |
9/27 (33.3) |
5/14 (35.7) |
1/17 (5.9) |
3/29 (10.3) |
2/18 (11.1) |
0/19 |
|
| Nasopharyngeal aspirate |
39/138 (28.3) |
15/44 (34.1) |
6/10 (60.0) |
23/171 (13.5) |
6/54 (11.1) |
0/9 |
|
| Throat swab |
5/19 (26.3) |
5/14 (35.7) |
3/10 (30.0) |
2/23 (8.7) |
0/15 |
1/15 (6.7) |
|
| Throat washing |
4/40 (10.0) |
13/58 (22.4) |
1/48 (2.1) |
0/36 |
1/62 (1.6) |
0/51 |
|
| Nonrespiratory |
|||||||
| Rectal swab |
5/11 (45.5) |
2/10 (20.0) |
3/7 (42.9) |
0/14 |
0/12 |
0/35 |
|
| Stool |
9/21 (42.9) |
17/25 (68.0) |
34/80 (42.5) |
2/24 (8.3) |
0/28 |
0/141 |
|
| Urine | 2/75 (2.7) | 5/82 (6.1) | 6/54 (11.1) | 0/110 | 0/86 | 2/76 (2.6) | |
aSARS-CoV, severe acute respiratory syndrome–associated coronavirus; RT-PCR, reverse transcription–polymerase chain reaction.
