Evaluation of a commercial real-time PCR kit for detection of dengue virus in samples collected during an outbreak in Goiania, Central Brazil, in 2005.
In the past 2 decades, dengue has reemerged in Brazil as a significant public health problem. Clinicians demand a diagnostic test with high sensitivity that is applicable during the early symptomatic phase. We aimed to test two distinct molecular methods on samples from suspected dengue cases during an outbreak in Central Brazil. Acute-phase serum specimens from 254 patients suspected of having dengue were collected during 2005 in the city of Goiânia, Central Brazil. Samples were blindly evaluated by real-time and multiplex PCR in addition to routine immunoglobulin M serology and virus culture. Overall, acute dengue was confirmed by serology, multiplex PCR, or virus isolation for 80% of patients (203/254). Another four patients presented real-time PCR-positive results as the unique marker of dengue. Higher real-time PCR positivity levels and viral loads were observed in the early symptomatic phase of disease (< or =5 days) than after this period. Multiplex and real-time PCR assays presented a high kappa agreement (0.85). According to multiplex PCR, 60 samples harbored dengue virus type 3 (DEN-3), 4 samples harbored DEN-2, and 1 sample displayed a pattern compatible with a double infection with DEN-2 and -3. The dengue virus real-time kit was found to be practical and adjustable for high throughput, to display the best performance in the early symptomatic phase of dengue cases, and to be valuable for confirming dengue diagnosis in a timely manner.
Levi
José Eduardo
JE
Laboratório de Virologia, LIM-HC da FMUSP e Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, São Paulo, Brazil. dudilevi@usp.br
Tateno
Adriana Fumie
AF
Machado
Adriana Freire
AF
Ramalho
Débora Camillo
DC
de Souza
Vanda Akico Ueda Fick
VA
Guilarde
Adriana Oliveira
AO
de Rezende Feres
Valéria Christina
VC
Martelli
Celina Maria Turchi
CM
Turchi
Marília Dalva
MD
Siqueira
João Bosco
JB
Pannuti
Cláudio Sérgio
CS
D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D003715:Dengue / Q000175:diagnosis* / Q000453:epidemiology* / Q000821:virology; D003716:Dengue Virus / Q000235:genetics / Q000302:isolation & purification*; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods*; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D011933:Reagent Kits, Diagnostic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
D012367:RNA, Viral; D011933:Reagent Kits, Diagnostic