@article{3183965,
    title = "The concordance of the limiting antigen and the Bio-Rad avidity assays
in persons from Estonia infected mainly with HIV-1 CRF06_cpx",
    author = "Huik, Kristi and Soodla, Pilleriin and Pauskar, Merit and Owen, S. and Michele and Luo, Wei and Murphy, Gary and Jogeda, Ene-Ly and Kallas, and Eveli and Rajasaar, Heli and Avi, Radko and Masciotra, Silvina and and Lutsar, Irja and Del Amo, Julia and Meyer, Laurence and Bucher, Heiner and C. and Chene, Genevieve and Hamouda, Osamah and Pillay, Deenan and and Prins, Maria and Rosinska, Magda and Sabin, Caroline and Touloumi, Giota and and Porter, Kholoud and Olson, Ashley and Cartier, Andrea and Fradette, and Lorraine and Walker, Sarah and Babiker, Abdel and De Luca, Andrea and and Fisher, Martin and Muga, Roberto and Kelleher, Tony and Cooper, David and and Grey, Pat and Finlayson, Robert and Bloch, Mark and Ramacciotti, Tim and and Gelgor, Linda and Smith, Don and Zangerle, Robert and Gill, John and and Dabis, Francois and Thiebaut, Rodolphe and Costagliola, Dominique and and Guiguet, Marguerite and Vanhems, Philippe and Chaix, Marie-Laure and and Ghosn, Jade and Boufassa, Faroudy and Meixenberger, Karolin and Bannert, and Norbert and Bartmeyer, Barbara and Antoniadou, Anastasia and Chrysos, and Georgios and Daikos, Georgios L. and Pantazis, Nikos and Katsarou, Olga and and Rezza, Giovanni and Dorrucci, Maria and Monforte, Antonella and d'Arminio and Geskus, Ronald and van der Helm, Jannie and Schuitemaker, and Hanneke and Sannes, Mette and Dyrhol-Riise, Anne Ma and Kran, Anne-Marte and Bakken and Rosinska, Magdalena and Tor, Jordi and de Olalla, Patricia and Garcia and Cayla, Joan and del Amo, Julia and Moreno, Santiago and and Monge, Susana and del Romero, Jorge and Perez-Hoyos, Santiago and and Sonnerborg, Anders and Guenthard, Huldrych and Scherrer, Alexandra and and Malyuta, Ruslan and Johnson, Anne and Phillips, Andrew and Morrison, and Charles and Salata, Robert and Mugerwa, Roy and Chipato, Tsungai and and Price, Matt A. and Gilmour, Jill and Kamali, Anatoli and Karita, Etienne and and Burns, Fiona and Giaquinto, Carlo and Grarup, Jesper and Kirk, Ole and and Bailey, Heather and Anne, Alain Volny and Panteleev, Alex and and Thorne, Claire and Aboulker, Jean-Pierre and Albert, Jan and Asandi, and Silvia and De Wit, Stephane and Reiss, Peter and Gatell, Jose and and Karpov, Igor and Ledergerber, Bruno and Lundgren, Jens and Moller, Claus and and Rakhma-nova, Aza and Rockstroh, Juergen and Sandhu, Manjinder and and Dedes, Nikos and Fenton, Kevin and Pizzuti, David and Vitoria, Marco and and Faggion, Silvia and Frost, Richard and Raben, Dorthe and Schwimmer, and Christine and Scott, Martin and CASCADE Collaboration EuroCoord",
    journal = "PLOS ONE",
    year = "2019",
    volume = "14",
    number = "5",
    publisher = "Public Library of Science",
    doi = "10.1371/journal.pone.0217048",
    abstract = "Background
Serological assays to determine HIV incidence have contributed to
estimates of HIV incidence, monitoring of HIV spread, and evaluation of
prevention strategies. Two frequently used incidence assays are the
Sedia HIV-1 LAg-Avidity EIA (LAg) and the Bio-Rad avidity incidence
(BRAI) assays with a mean duration of recent infection (MDRI) of 130 and
240 days for subtype B infections, respectively. Little is known about
how these assays perform with recombinant HIV-1 strains. We evaluated
the concordance of these assays in a population infected mainly with
HIV-1 CRF06_cpx.
Material/Methods
Remnant serum samples (n = 288) collected from confirmed,
newly-diagnosed HIV-positive persons from Estonia in 2013 were tested.
Demographic and clinical data were extracted from clinical databases.
LAg was performed according to the manufacturer’s protocol and BRAI
testing was done using a validated protocol. Samples with LAg-pending or
BRAI-invalid results were reclassified as recent if they were from
persons with viral loads <1000 copies/mL or were reclassified as
long-term if presenting with AIDS.
Results
In total 325 new HIV infections were diagnosed in 2013 in Estonia. Of
those 276 persons were tested with both LAg and BRAI. Using assay
results only, the recency rate was 44% and 70% by LAg and BRAI,
respectively. The majority of samples (92%) recent by LAg were recent
by BRAI. Similarly, 89% of samples long-term by BRAI were long-term by
LAg. After clinical information was included in the analysis, the
recency rate was 44% and 62% for LAg and BRAI, respectively. The
majority of samples (86%) recent by LAg were recent by BRAI and 91% of
long-term infections by BRAI were long-term by LAg.
Conclusions
Comparison of LAg and BRAI results in this mostly CRF06_cpx-infected
population showed good concordance for incidence classification. Our
finding of a higher recency rate with BRAI in this population is likely
related to the longer MDRI for this assay."
}