Detection of hepatitis E virus genotype 3 in wastewater by an electrochemical genosensor.

Hepatitis E Virus (HEV) is an etiologic agent of hepatitis worldwide. HEV genotype 3 is the most prevalent in non-endemic regions, identified in humans, pigs and environmental samples. Thus, considering the zoonotic nature of HEV genotype 3, viral genome detection in wastewater concerns public health authorities. Electrochemical biosensors are promising analytical tools for viral genome detection in outside settings. This work reports on a highly specific, sensitive and portable electrochemical genosensor to detect HEV genotype 3 in wastewater samples. Based on the alignment analysis of HEV genotype 3 genome sequences available in GenBank, highly specific DNA target probes were designed to hybridize a target sequence within the ORF2/ORF3 overlapping genome region of HEV in between a biotinylated capture probe and a signal probe labeled with digoxigenin, in a sandwich-type format. An anti-Dig antibody labeled with the horseradish peroxidase (HRP) enzyme allowed electrochemical detection. The specificity of the target molecular probes of the viral genome was determined before the biosensor assembly by in silico analysis, PCR and qPCR assays demonstrating efficient amplification of two targets, i.e., nucleotides 5338-5373 and 5328-5373, but this last one of higher performance. The electrochemical response of the genosensor with synthetic HEV was target concentration-dependent in a linear range from 300 pM to 2.4 nM, with a sensitivity of 16.93 µA/nM, a LOD 1.2 pM and high reproducibility. The genosensor response was differential when interrogated with the HEV genotype 3 viral genomes from wastewater against other four viruses. Therefore, the approach offers a step forward to the epidemiologic surveillance of viruses in wastewater as an early warning system.

Genetic diversity of hepatitis C virus and resistance associated substitutions to direct-acting antiviral treatment in Colombia.

Hepatitis C virus (HCV) infection is one of the leading risk factors for end-stage liver disease development worldwide. This RNA virus displays high genetic diversity with 8 genotypes and 96 subgenotypes with heterogeneous geographical distribution around the world. In this study, we carried out an active case finding of individuals with a history of transfusion events before 1996 in three cities in Colombia. Then, the characterization of the HCV genotypes, subgenotypes, and resistance associate substitutions (RAS) was performed in samples positives for antibodies anti-HCV + from this study population. In addition, samples from PWID and patients with end-stage liver disease submitted to liver transplantation were included in the phylogenetic and RAS analysis. The 5'UTR, NS5A, and NS5B regions of the HCV genome were amplified in serum or liver explants samples. After the edition, assembly, and alignment of the sequences, genotyping through phylogenetic analysis was performed using IQTREE V2.0.5 based on the maximum likelihood approach. The identification of RAS was carried out by alignments based on the reference sequence (GenBank NC_004102). Two hundred sixty individuals with blood transfusion events before 1996 were recruited. The seroprevalence of antibodies anti-HCV was 2.69% in this population. The HCV genotypes 1, 2, and 4 and subgenotypes 1a, 1b, 2a, 4a and 4d were characterized in samples of the study populations. Three RAS (Q30R, C316N, and Y93H) were identified in samples obtained from 2 individuals who received blood transfusion before 1996 and without previous antiviral treatment and 6 samples obtained from patients with end-stage liver disease. Among the 20 samples analyzed, the HCV genotype 1, subgenotype 1b, was the most frequent (60%). We report the first characterization of HCV subgenotypes 4a and 4d and the first RAS identification in patients in Colombia.

[Epidemiology of hepatitis C virus infection in ColombiaEpidemiologia da infecção pelo vírus da hepatite C na Colômbia]. / Epidemiología de la infección por el virus de la hepatitis C en Colombia.

OBJECTIVE: To describe the epidemiology of hepatitis C virus (HCV) infection in Colombia. METHODS: Critical review of epidemiological studies of HCV infection in Colombia. The PubMed, SciELO, and ScienceDirect databases were searched for original articles and reviews on the subject published from 1989 to 2020. Reports from the National Institute of Health and the High Cost Account of the Ministry of Health and Social Protection were also reviewed. RESULTS: Data on seroprevalence of HCV antibodies in blood donors range from 1.5% to 0.32%, corresponding to reports at the beginning and end of the study period, respectively. In the population with risk factors, a high prevalence of HCV infection is observed, although with variations over time. With respect to HCV genotypes in Colombia, genotypes 1, 2, 3, and 4 (subtypes 1a, 1b, 2a, and 3a) have been identified. CONCLUSIONS: In the observation period, a decrease was seen in seroprevalence of HCV infection in blood donors and hemodialysis patients in Colombia, demonstrating the impact of safe blood policies and biosafety measures. Studies in people who inject illicit drugs indicate a high prevalence of infection, with regional differences within the country. HCV genotype 1, subtype 1b, is the most frequent in the different studies carried out in Colombia, and the most recent report of the High Cost Account of the Ministry of Health and Social Protection indicates that genotype 4 is the second most frequent genotype in the country.

OBJETIVO: Descrever a epidemiologia da infecção pelo vírus da hepatite C na Colômbia. MÉTODOS: Foi realizada uma revisão crítica de estudos epidemiológicos sobre a infecção pelo HCV na Colômbia por meio de busca de artigos originais e revisões a respeito do tema, publicados no período de 1989 a 2020, nos bancos de dados PubMed, SciELO e ScienceDirect. Também foram analisados os relatórios do Instituto Nacional de Saúde e da Conta de Alto Custo do Ministério da Saúde e Proteção Social. RESULTADOS: O índice de soroprevalência de anticorpos anti-HCV em doadores de sangue varia de 1,5% a 0,32%, correspondendo aos relatos do início e do final do período de estudo, respectivamente. Na população com fatores de risco, observa-se prevalência elevada de infecção pelo HCV, embora com variações ao longo do tempo. Em relação aos genótipos do HCV, foram identificados os genótipos 1, 2, 3 e 4 (subgenótipos 1a, 1b, 2a e 3a) na Colômbia. CONCLUSÕES: No período de interesse, observa-se uma diminuição da soroprevalência da infecção pelo HCV em doadores de sangue e em pacientes em tratamento hemodialítico na Colômbia, o que demonstra o impacto das políticas de sangue seguro e medidas de biossegurança. Estudos com usuários de drogas ilícitas injetáveis indicam alta prevalência de infecção, com diferenças de acordo com a região do país. O subgenótipo 1b do genótipo 1 do HCV é o mais prevalente nos diferentes estudos realizados na Colômbia, enquanto o informe mais recente da Conta de Alto Custo do Ministério da Saúde e Proteção Social indica que o genótipo 4 é o segundo mais frequente no país.