An Automated Immunoblot Method for Detection of IgG Antibodies to Hepatitis C Virus: a Potential Supplemental Antibody Confirmatory Assay.

An estimated 41,200 people were newly infected with hepatitis C virus (HCV) in 2016 in the United States. Screening tests for antibodies to HCV may generate up to 32% false positivity in low-risk populations. Current Centers for Disease Control and Prevention (CDC) screening recommendations do not require confirmatory testing of a screening anti-HCV-positive test; however, confirmation is valuable for surveillance in the absence of HCV RNA testing. A recombinant immunoblot assay (RIBA) was used as a confirmatory assay for anti-HCV-reactive samples but was discontinued in 2013. Another anti-HCV confirmatory assay, INNO-LIA, is commercially available in Europe but is not approved by the Food and Drug Administration (FDA) in the United States. We report the development of an anti-HCV assay that was performed on an automated immunoblot platform using a fourth-generation HCV recombinant fusion protein. Based on testing of 70 well-characterized samples, of which 40 were HCV RNA and anti-HCV positive, 15 were HCV RNA positive/anti-HCV negative, and 15 were HCV RNA and anti-HCV negative, the specificity and sensitivity of the HCV-WES assay were 100% and 95%, respectively. Concordance between INNO-LIA and HCV-WES was determined by testing 205 HCV RNA-negative/anti-HCV-positive samples, of which 149 (72.7%) were positive by HCV-WES, while 146 (71.2%) were positive by INNO-LIA. We have shown proof of concept for the use of this test for confirmation of screened anti-HCV results. The HCV-WES assay has advantages over manual Western blot assays and INNO-LIA, including ease of use, lower cost, and reduced hands-on time.

Anti-Leishmania antibodies in blood donors from the Midwest region of Brazil.

The aim of the study was to detect asymptomatic infection by Leishmania sp. in blood donors. Serum samples (430) were tested by Immunofluorescent Antibody Test, and an interview with the blood donors was carried out. Antibodies were detected in 15.6% of samples. The variables associated with the infection were: origin of the donor, presence of builds, parks or squares, sick dog in the neighborhood, and neighboring with leishmaniasis. It was observed association between origin of donors and the presence of sick dog. It is important a careful screening of donors, due to the risk of infection through blood transfusion.