Evaluation of the Diagnostic Accuracy of a New Dengue IgA Capture Assay (Platelia Dengue IgA Capture, Bio-Rad) for Dengue Infection Detection

<div><p>Considering the short lifetime of IgA antibodies in serum and the key advantages of antibody detection ELISAs in terms of sensitivity and specificity, Bio-Rad has just developed a new ELISA test based on the detection of specific anti-dengue IgA. This study has been carried out to assess the performance of this Platelia Dengue IgA Capture assay for dengue infection detection. A total of 184 well-characterized samples provided by the French Guiana NRC sera collection (Laboratory of Virology, Institut Pasteur in French Guiana) were selected among samples collected between 2002 and 2013 from patients exhibiting a dengue-like syndrome. A first group included 134 sera from confirmed dengue-infected patients, and a second included 50 sera from non-dengue infected patients, all collected between day 3 and day 15 after the onset of fever. Dengue infection diagnoses were all confirmed using reference assays by direct virological identification using RT-PCR or virus culture on acute sera samples or on paired acute-phase sera samples of selected convalescent sera. This study revealed: i) a good overall sensitivity and specificity of the IgA index test, i.e., 93% and 88% respectively, indicating its good correlation to acute dengue diagnosis; and ii) a good concordance with the Panbio IgM capture ELISA. Because of the shorter persistence of dengue virus-specific IgA than IgM, these results underlined the relevance of this new test, which could significantly improve dengue diagnosis accuracy, especially in countries where dengue virus is (hyper-) endemic. It would allow for additional refinement of dengue diagnostic strategy.</p></div

Description of serum samples (n = 184) used for evaluating the performance of the Platelia Dengue IgA Capture test according to the DENV serotype and the number of days after fever onset.

<p>Sera were collected between the 3^rd and the 15^th day following the onset of fever (<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003596#pntd.0003596.t001" target="_blank">Table 1</a>). The median (Interquartile 1-Interquartile 3, IQ1-IQ3) number of days between onset of fever and sample collection is 9 (7–10) and 8 (6–11) after the onset of fever for the non-dengue group and the dengue group, respectively.</p><p>Description of serum samples (n = 184) used for evaluating the performance of the Platelia Dengue IgA Capture test according to the DENV serotype and the number of days after fever onset.</p

Platelia Dengue IgA Capture index test and Panbio Dengue IgM kit ROC curves.

<p>Platelia Dengue IgA Capture index test and Panbio Dengue IgM kit ROC curves.</p

IgA detection using Platelia Dengue IgA Capture assay in relation to DENV infecting serotype.

<p>IgA detection using Platelia Dengue IgA Capture assay in relation to DENV infecting serotype.</p

IgA detection using Platelia Dengue IgA Capture assay in relation to immune status.

<p>IgA detection using Platelia Dengue IgA Capture assay in relation to immune status.</p

Estimated performances of Platelia Dengue IgA Capture assay.

<p>Estimated performances of Platelia Dengue IgA Capture assay.</p

Odds ratio from the adjusted mixed model for abstinence from opioids use during the treatment (n = 615 visits and 188 patients).

<p>Odds ratio from the adjusted mixed model for abstinence from opioids use during the treatment (n = 615 visits and 188 patients).</p

Features of the PC and SC model of care for methadone treatment (ANRS Methaville trial).

<p>Features of the PC and SC model of care for methadone treatment (ANRS Methaville trial).</p

Flow chart of ANRS Methaville trial.

<p>Flow chart of ANRS Methaville trial.</p

Retention in methadone maintenance treatment in patients (who completed the induction phase) in primary care (PC) versus those who started in specialized care (SC).

<p>Retention in methadone maintenance treatment in patients (who completed the induction phase) in primary care (PC) versus those who started in specialized care (SC).</p