Hepatitis A: an epidemiological survey in blood donors, France 2015 to 2017.

Since mid-2016, hepatitis A virus (HAV) outbreaks, involving predominantly men who have sex with men (MSM), have affected countries in Europe and overseas. In France, HAV screening of blood donations in 2017 revealed a HAV-RNA prevalence ca fivefold higher than during 2015-16 (4.42/106 vs 0.86/106; p = 0.0005). In 2017, despite a higher male-to-female ratio (5.5 vs 0.7) and the identification of MSM-associated outbreak strains, only one of 11 infected male donors self-reported being a MSM.

Testing blood donors for Chagas disease in the Paris area, France: first results after 18 months of screening.

BACKGROUND: Chagas disease is endemic in Latin America (LA). Currently 10 million people are infected despite World Health Organization efforts aimed at preventing domestic transmission. However, with the migration of infected asymptomatic individuals to nonendemic countries, transmission of Chagas disease by transfusion may become a worldwide problem. The observation that the number of cases of Chagas disease has increased over the past 10 years in French Guiana, together with the results of a previous hospital-based study in the Paris area, confirms the transmission of Chagas disease from patients coming from LA. For these reasons, the French authorities stopped the collection of blood in French Guiana in 2005 and began screening blood donors in the French Caribbean islands and, in 2007, in continental France. STUDY DESIGN AND METHODS: Data on birth place, mother's birth place, and travel in LA were recorded for at-risk donors. These subjects were tested using two enzyme-linked immunosorbent assays (ELISAs). RESULTS: Of the 312,458 individuals who gave blood in the Paris area during an 18-month period, 30,837 were tested. Of these, 972 were born in LA, three of whom were positive for the two ELISAs and immunofluorescence tests. The prevalence of Trypanosoma cruzi-positive donors was 9.7 in 100,000 tested donors, but 0.31% among donors born in LA. Serology tests gave discrepant results in 1.02% of the samples. CONCLUSION: The efficiency of blood donor screening programs could be improved by screening only blood donors who were born in LA or who have traveled in LA for extended periods, using a single enzyme immunoassay.

Variable capacity of 13 hepatitis B virus surface antigen assays for the detection of HBsAg mutants in blood samples.

BACKGROUND: Natural variation and mutations in the envelope protein (S) of hepatitis B virus can translate into HBsAg variants no longer detectable by conventional HBsAg assays. OBJECTIVES: The aim of the study was to assess the performance of 13 commercial assays currently used for screening and clinical analysis of HBsAg variants. STUDY DESIGN: The limit of detection (LOD) for each assay was established using two reference standards (WHO HBsAg 00/588 and the SFTS French reference). Sensitivity was evaluated using different panels. Panel 1 included 25 recombinant HBs variants at three concentrations, panels 2 and 4 included 8 recombinant HBsAg variants and 9 wild-type proteins (genotypes A-F), respectively, panel 3 included 16 natural HBsAg variants. RESULTS: LODs ranged from 0.011 to 0.095 IU/ml with the WHO standard, and from 0.021 to 0.326 ng/ml with the French reference. The overall percentage of positive signals using HBsAg variants ranged from 62.9% to 97.9%. Three substitutions: T123, D144A and G145, were negative at all concentrations with at least one assay. DISCUSSION: Our findings show that, although they fulfil CE requirements for analytical sensitivity (LODs below 0.13 IU/ml), HBsAg assays may vary in their capacity to detect HBsAg variants. This limit in diagnosis performance should encourage the health regulatory agencies to include HBsAg variant panels in the evaluation process.