Internally Controlled, Generic Real-Time PCR for Quantification and Multiplex Real-Time PCR with Serotype-Specific Probes for Serotyping of Dengue Virus Infections
Table 6
Summary of patient characteristics and sensitivity and specificity of PCR assays.
Patient characteristics and test parameters
Vietnamese patients with DENV
Ill-returned travelers with DENV
Other causes of fever in travelers
Patients positive for
Primary infection
Secondary infection
Primary infection
Secondary infection
OFI
HCV/HAV
Total
Patients (n)
5
67
21
16
9
(18)d
136
Age; median (range)
10.9 (6.6–12.8)
18.9 (5.6–53.1)
38.7 (17.4–62.6)
33.2 (24.6–73.6)
39.5 (26.3–64.0)
unknown
26.3 (6.6–73.6)
Sex (M/F)
3/2
48/19
9/12
6/10
6/3
unknown
72/46
Days of illness at presentation; median (range)
1 (1-1)
1 (1–4)
6 (1–12)
8.5 (4–22)
—
—
2 (1–22)
Days of DENV viremia; median (range)
1 (1-1)
1 (1–4)
4 (1–11)
7 (4–9)
—
—
1 (1–11)
Patients () with a positive result in
Type-specific PCRa
5
66
16
9
0
ND
96
Generic PCRb
3
66
15
8
0
0
92
Multiplex PCRc
3
63
11
3
0
ND
80
Assay characteristics of Generic PCR
Sensitivity; % (95% CI)
60.0 (23.1–88.2)
100.0 (94.5–100.0)
93.8 (71.7–99.0)
88.9 (56.5–98.0)
—
—
95.8 (89.8–98.4)
κ-value
0.736
1.000
0.944
0.924
0.846
Specificity; %
100.0
100.0
100.0
aThe results were earlier generated by the type-specific primer PCR according to according Laue et al. [11, 16, 17].
bInternally controlled generic real-time PCR for DENV.
cMultiplex PCR with type-specific probes was only done on samples with a positive generic PCRbresult.
d16 patients were antibody and PCR positive for HCV and 2 patients were antibody and PCR positive for HAV. OFI: other febrile illness; HCV: hepatitis C virus; HAV: hepatitis A virus; M: male; F: female; 95% CI: 95% confidence interval, ND: not done.
