title: Evaluation of a dengue NS1 antigen detection assay sensitivity and specificity for the diagnosis of acute dengue virus infection.
abstract: BACKGROUND
  Currently, no dengue NS1 detection kit has regulatory approval for the diagnosis of acute dengue fever. Here we report the sensitivity and specificity of the InBios DEN Detect NS1 ELISA using a panel of well characterized human acute fever serum specimens.
  
  
  RESULTS
  The InBios DENV Detect NS1 ELISA was tested using a panel composed of 334 serum specimens collected from acute febrile patients seeking care in a Bangkok hospital in 2010 and 2011. Of these patients, 314 were found to have acute dengue by either RT-PCR and/or anti-dengue IgM/IgG ELISA. Alongside the InBios NS1 ELISA kit, we compared the performance characteristics of the BioRad Platelia NS1 antigen kit. The InBios NS1 ELISA Ag kit had a higher overall sensitivity (86% vs 72.8%) but equal specificity (100%) compared to the BioRad Platelia kit. The serological status of the patient significantly influenced the outcome. In primary infections, the InBios NS1 kit demonstrated a higher sensitivity (98.8%) than in secondary infections (83.5%). We found significant variation in the sensitivity of the InBios NS1 ELISA kit depending on the serotype of the dengue virus and also found decreasing sensitivity the longer after the onset of illness, showing 100% sensitivity early during illness, but dropping below 50% by Day 7.
  
  
  CONCLUSIONS
  The InBios NS1 ELISA kit demonstrated high accuracy when compared to the initial clinical diagnosis with greater than 85% agreement when patients were clinically diagnosed with dengue illness. Results presented here suggest the accurate detection of circulating dengue NS1 by the InBios DENV Detect NS1 ELISA can provide clinicians with a useful tool for diagnosis of early dengue infections.
authors.affiliation: Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: Laura L
authors.initials: LL
authors.lastname: Hermann
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: Butsaya
authors.initials: B
authors.lastname: Thaisomboonsuk
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: Yongyuth
authors.initials: Y
authors.lastname: Poolpanichupatam
authors.affiliation: Viral Diseases Branch, Walter Reed Army Institute of Research, Washington D.C., United States of America.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Jarman
authors.affiliation: Queen Sirikit National Institute of Child Health, Bangkok, Thailand.
authors.forename: Siripen
authors.initials: S
authors.lastname: Kalayanarooj
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: Ananda
authors.initials: A
authors.lastname: Nisalak
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: In-Kyu
authors.initials: IK
authors.lastname: Yoon
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
authors.forename: Stefan
authors.initials: S
authors.lastname: Fernandez
mesh_terms: D000293:Adolescent; D000328:Adult; D000956:Antigens, Viral / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000097:blood / Q000175:diagnosis* / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D017361:Viral Nonstructural Proteins / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: D000956:Antigens, Viral; D011933:Reagent Kits, Diagnostic; D017361:Viral Nonstructural Proteins