title: Evaluating HBsAg rapid test performance for different biological samples from low and high infection rate settings & populations.
abstract: BACKGROUND
  Rapid tests (RTs) might have several advantages over standard laboratory procedures, increasing access to diagnosis, especially among vulnerable populations and/or those living in remote areas. The aim of this study was to evaluate the performance of RTs for the detection of hepatitis B virus surface antigen (HBsAg) in samples from different populations/settings.
  
  
  METHODS
  Three RTs for HBsAg detection (Vikia® HBsAg, HBsAg Teste Rápido®, and Imuno-Rápido HBsAg®) and different biological specimens (serum, whole blood, and saliva) were evaluated. Analyses comprised a reference panel and samples from field studies targeting suspected cases of hepatitis B virus (HBV) (G I), individuals living in deprived areas (G II), and highly vulnerable individuals (G III). Enzyme immunoassay (EIA) was defined as the gold standard in this study. Reproducibility, repeatability, and cross-reactivity with other infectious agents such as dengue, immunodeficiency (HIV), and hepatitis C (HCV) viruses and T. pallidum were determined.
  
  
  RESULTS
  For the reference panel, the sensitivity and specificity of all HBsAg RTs were higher than 93.00 %. G I presented the highest kappa values for all rapid assays using sera samples. When using serum, the sensitivity values were higher than 93.40 for G I, 60.00 % for G II and 66.77 % for G III, and the specificity values were higher than 99.50 for GI, 97.20 for G II and 99.10 % for G III for all tests. For whole blood samples & the Vikia® HBsAg assay, the best performance was achieved for GIII (k = 79.75 %). For saliva samples, the Imuno-Rápido HBsAg® assay showed the highest concordance values with EIA for G I (40.68 %) and G II (32.20 %). The reproducibility and repeatability of all RTs for serum and saliva were excellent, and the concordance between HBsAg EIAs and RTs using samples reactive with other infectious agents varied from 70.10 % to 100.00 %.
  
  
  CONCLUSIONS
  The overall performance of RTs for HBsAg in serum was high/moderately high for all groups, thereby promoting increased access to HBV diagnosis among vulnerable populations as well as samples from individuals in emergency settings or remote areas. Rapid tests for HBsAg using whole blood could be used in prevalence studies, though these assays should not be used for saliva samples.
authors.affiliation: Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. h.medina@ioc.fiocruz.br.
authors.forename: Helena Medina
authors.initials: HM
authors.lastname: Cruz
authors.affiliation: Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. lescali@ioc.fiocruz.br.
authors.forename: Leticia de Paula
authors.initials: Lde P
authors.lastname: Scalioni
authors.affiliation: Laboratory of Technological Development of Virology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. vdepaula@ioc.fiocruz.br.
authors.forename: Vanessa Salete
authors.initials: VS
authors.lastname: de Paula
authors.affiliation: Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. elis-ferreira@ioc.fiocruz.br.
authors.forename: Elisangela Ferreira
authors.initials: EF
authors.lastname: da Silva
authors.affiliation: São Lucas Hospital, Petropolis, Rio de Janeiro, Brazil. kyciadoo@gmail.com.
authors.forename: Kycia Maria Rodrigues
authors.initials: KM
authors.lastname: do Ó
authors.affiliation: Medicine Faculty, Federal University of Tocantins, Palmas, Brazil. flaviomilagres@uft.edu.br.
authors.forename: Flavio Augusto Pádua
authors.initials: FA
authors.lastname: Milagres
authors.affiliation: Institute of Psychiatry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. marcelosantoscruz@ipub.ufrj.br.
authors.forename: Marcelo Santos
authors.initials: MS
authors.lastname: Cruz
authors.affiliation: Institute of Communication and Scientific Information & Technology for Health, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil. francisco.inacio.bastos@hotmail.com.
authors.forename: Francisco Inácio
authors.initials: FI
authors.lastname: Bastos
authors.affiliation: Antonio Pedro University Hospital, Federal Fluminense University, Rio de Janeiro, Brazil. priscilapollo96@gmail.com.
authors.forename: Priscila
authors.initials: P
authors.lastname: Pollo-Flores
authors.affiliation: Federal University of Rio de Janeiro, Campus Macaé, Rio de Janeiro, Brazil. eroleal@gmail.com.
authors.forename: Erotildes
authors.initials: E
authors.lastname: Leal
authors.affiliation: Federal University of Mato Grosso do Sul and FIOCRUZ-MS, Campo Grande, MS, Brazil. arcm.castro@hotmail.com.
authors.forename: Ana Rita Coimbra
authors.initials: AR
authors.lastname: Motta-Castro
authors.affiliation: Laboratory of AIDS and Molecular Immunology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. pilotto@ioc.fiocruz.br.
authors.forename: José Henrique
authors.initials: JH
authors.lastname: Pilotto
authors.affiliation: Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. llewis@ioc.fiocruz.br.
authors.forename: Lia Laura
authors.initials: LL
authors.lastname: Lewis-Ximenez
authors.affiliation: Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. elampe@ioc.fiocruz.br.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Lampe
authors.affiliation: Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. liviafiocruz@gmail.com.|Present address: Viral Hepatitis Laboratory, Helio and Peggy Pereira Pavilion - Ground, Floor - Room B09, FIOCRUZ Av. Brazil, 4365 - Manguinhos, Rio de Janeiro, RJ, 210360-040, Brazil. liviafiocruz@gmail.com.
authors.forename: Livia Melo
authors.initials: LM
authors.lastname: Villar
mesh_terms: D000328:Adult; D003429:Cross Reactions / Q000276:immunology; D005260:Female; D016174:Hepacivirus / Q000276:immunology; D006509:Hepatitis B / Q000097:blood / Q000175:diagnosis*; D006514:Hepatitis B Surface Antigens / Q000032:analysis / Q000097:blood*; D006515:Hepatitis B virus / Q000276:immunology; D006526:Hepatitis C / Q000175:diagnosis / Q000821:virology; D018937:Hepatitis C Antibodies / Q000097:blood; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies