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This review aims to gather and disseminate updated information regarding hepatitis A virus (HAV) in Latin America (LA) in the last 11 years, including seroprevalence, post-vaccination studies, virus detection in aqueous matrices and food samples, and outbreak reports. Only 24 seroprevalence studies were published between 2012 and 2023 with 55%-100% reported prevalences of anti-HAV IgG. Among the 25 LA countries, only eight of them have introduced HAV vaccines into their immunisation programs. Outbreaks of hepatitis A occurred between 2017-2019, mainly affecting men who have sex with men in Argentina, Brazil and Chile, probably as a consequence of the abrupt decline of young adults' immunity. This could be due to that young adult have never been infected in childhood (due to socio-health improvements) and are above the cut-off ages to be included when the vaccination programs were introduced. Although scarce, studies focused on environmental and food HAV surveillance have shown viral presence in these samples. Surface waters presented HAV detections between 1.2% and 86.7%, and untreated wastewaters between 2.8% and 70.9%. Genotypes found in all cases were IA and IC. The only wastewater-based epidemiology study showed to be a useful tool as a complement of traditional epidemiological surveillance. Only four LA countries have looked for HAV in food samples, with genome detection rates between 9% and 33%. Latin American HAV circulation scenario is changing. In countries where socioeconomic and sanitary conditions have not improved, the virus persists with high endemicity and the access to the vaccine should be re-evaluated by local governments. In countries where access to clean water, better sanitary conditions and HAV immunisation programs have been implemented, the number of cases among young adults seems to be increasing, alerting health authorities.
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Vacunas contra la Hepatitis A , Virus de la Hepatitis A , Hepatitis A , Hepatitis A/epidemiología , Hepatitis A/virología , Hepatitis A/prevención & control , Humanos , América Latina/epidemiología , Estudios Seroepidemiológicos , Virus de la Hepatitis A/inmunología , Virus de la Hepatitis A/genética , Virus de la Hepatitis A/aislamiento & purificación , Vacunas contra la Hepatitis A/administración & dosificación , Vacunas contra la Hepatitis A/inmunología , Brotes de Enfermedades , Anticuerpos de Hepatitis A/sangre , GenotipoRESUMEN
The rocketing number of COVID-19 cases highlighted the critical role that diagnostic tests play in medical and public health decision-making to contain and mitigate the SARS-CoV-2 pandemic. This study reports the evaluation and implementation of different tests for the molecular detection of SARS-CoV-2 in the central region of Argentina. We evaluated 3 real time RT-PCR kits (GeneFinder COVID-19 Plus RealAmp Kit, DisCoVery SARS-CoV-2 RT-PCR Detection Kit and WGene SARS-CoV-2 RT Detection), 2 nucleic acid extraction methods [MagaBio plus Virus DNA/RNA Purification Kit II (BioFlux), 35-min vs. 9-min], a pre-analytical reagent (FlashPrep®) and 2 isothermal amplification tests (Neokit Plus and ELA CHEMSTRIP®). The order according to the best performance of the 3 real-time RT-PCR kits evaluated was: DisCoVery>GeneFinderTM>WGene. The 2 RNA extraction methods showed similar good results: MagaBio plus Virus RNA Purification Kit II (BioFlux) 9-min was selected due to its faster performance. FlashPrep® reagent showed excellent results to perform direct RNA detection. Isothermal amplification assays showed acceptable sensitivity and specificity values (>80%), except in samples with Ct>30. Our data show optimal real time RT-PCR kits and alternative molecular methods for SARS-CoV-2 diagnostic. These alternative assays proved to be acceptable for their use in adverse contexts, decentralization, and different epidemiological scenarios, for rapid and accurate SARS-CoV-2 detection.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Argentina , Sensibilidad y Especificidad , ARN Viral/genética , ARN Viral/análisis , Política , Técnicas de Diagnóstico Molecular/métodos , Prueba de COVID-19RESUMEN
BACKGROUND: The hepatitis E virus (HEV) infection has been described as a causing factor for acute-on-chronic-liver-failure (ACLF) in patients with underlying chronic liver disease (CLD), such as chronic hepatitis or cirrhosis, which could end in the failure of one or more organs and high short-term mortality. There are scarce data about the association of HEV in patients with chronic liver disorders in South America. CASE PRESENTATION: A 56-year-old hypertensive male with a history of type 2 diabetes was diagnosed with alcohol-related-liver cirrhosis in February 2019. A year later, the patient was admitted to hospital due to fatigue, jaundice and acholia. No evidence of hepatitis A virus, hepatitis B virus, hepatitis C virus, Epstein-Barr virus, herpes zoster virus and cytomegalovirus infections were found. Nevertheless, in February and March, 2020 the patient was positive for HEV-IgM and HEV-IgG, and HEV genotype 3 RNA was detected in sera. Afterwards, he presented grade I hepatic encephalopathy and, therefore, was diagnosed with acute hepatitis E-on-chronic liver disease. The patient reported a recent travel to the Argentine coast, where he consumed seafood. Besides, he reveled to have consumed pork meat and had no history of blood transfusion. CONCLUSION: This report describes a unique case of hepatitis E virus infection in a patient with alcohol-related cirrhosis. This is the first report of a patient with HEV-related ACLF in Argentina and it invokes the importance of HEV surveillance and treatment among patients with CLD, such as alcohol-related cirrhosis.
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Insuficiencia Hepática Crónica Agudizada , Diabetes Mellitus Tipo 2 , Infecciones por Virus de Epstein-Barr , Virus de la Hepatitis E , Hepatitis E , Insuficiencia Hepática Crónica Agudizada/complicaciones , Insuficiencia Hepática Crónica Agudizada/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Infecciones por Virus de Epstein-Barr/complicaciones , Hepatitis E/complicaciones , Hepatitis E/diagnóstico , Hepatitis E/epidemiología , Virus de la Hepatitis E/genética , Herpesvirus Humano 4 , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Hepatitis E virus (HEV) infection is an important cause of acute hepatitis worldwide. In pregnant women, HEV can cause more severe symptoms, with high rates of fatal hepatic failure in endemic countries. However, HEV prevalence and circulation among pregnant women from South America is almost unknown. We aimed to investigate HEV infection in pregnant women for the first time in Argentina. METHODS: IgG and IgM anti-HEV antibodies and RNA-HEV were investigated (by ELISA assays and RT-Nested-PCR, respectively) in 202 serum samples from pregnant women collected in the central region of Argentina between 2015 and 2017. A control group of 155 non-pregnant women was included (year 2018). RESULTS: The IgG anti-HEV positivity rate was 8.4% (17/202), higher than the 2.6% (4/155) obtained for the non-pregnant women control group, and showing association between pregnancy and HEV infection (p = 0.023, OR = 3.5, CI95% = 1.1-10.5). Women younger than 25 years old presented higher levels of antibodies, and there were no differences in the prevalences between trimesters of pregnancy. Two samples were reactive for IgM anti-HEV, showing recent infections, although no symptoms were registered in these patients. All samples were negative for RNA-HEV amplification. CONCLUSIONS: HEV produces infections in pregnant women from Argentina, alerting health teams to consider it as a possible cause of liver disease.
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Virus de la Hepatitis E/genética , Virus de la Hepatitis E/inmunología , Hepatitis E/diagnóstico , Hepatitis E/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/virología , Adolescente , Adulto , Argentina/epidemiología , Grupos Control , Ensayo de Inmunoadsorción Enzimática , Femenino , Anticuerpos Antihepatitis/sangre , Hepatitis E/virología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Reacción en Cadena de la Polimerasa , Embarazo , Prevalencia , ARN Viral/genética , ARN Viral/inmunología , Estudios Retrospectivos , Estudios Seroepidemiológicos , Adulto JovenRESUMEN
Infection with hepatitis E virus (HEV) leads to acute hepatitis infection in immunocompetent hosts. HEV genotype 3 can present with high frequency and lead to chronic infection in individuals with a compromised immune system. The risk factors related to increased seroprevalence or chronicity in this population are not entirely understood. Moreover, most studies addressing risk factors for HEV in non-endemic areas come from developed areas such as North America and Europe. In this study we evaluated seroprevalence, chronicity and risk factors for HEV in 120 transplant recipients and 88 patients on dialysis in Argentina. We found a significantly higher seroprevalence of HEV IgG in those undergoing dialysis compared with healthy controls (10.2% and 4.3% respectively, p = 0.03). No difference in HEV seroprevalence was observed between healthy controls and transplant recipients (5.8%). We found no association between previously identified risk factors for HEV, such as pork consumption or use of tacrolimus, and HEV seroprevalence. In univariate and multivariate analyses, consumption of fish was associated with higher seroprevalence of HEV (OR = 9.33; 95% CI: 2.07-42.2; p = 0.04). None of the samples showed HEV RNA amplification, indicating that chronicity does not seem to be an issue in these cohorts. Our results show increased seroprevalence of HEV in individuals undergoing dialysis but not in transplant recipients. We also found that fish consumption can be a potential risk factor for acquiring HEV.
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Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/virología , Trasplante de Riñón/efectos adversos , Diálisis Renal/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Argentina/epidemiología , Estudios de Cohortes , Ingestión de Alimentos , Femenino , Anticuerpos Antihepatitis/sangre , Hepatitis E/sangre , Hepatitis E/epidemiología , Hepatitis E/etiología , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/inmunología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estudios Seroepidemiológicos , Receptores de Trasplantes/estadística & datos numéricos , Adulto JovenRESUMEN
This study describes the prevalence of HBV infection based on detection of HBsAg and HBV-DNA by NAT in 70,102 blood donors in Argentina (Córdoba province) and shows the viral genotype distribution and frequency of occult HBV infection (OBI) in this population. Forty-two donors were confirmed positive for HBV infection (0.06 %), and four had OBI. Genotype F was the most prevalent (71.4 %), followed by A (14.3 %), C (7.1 %) and D (7.1 %). This is the first report of the prevalence of confirmed HBV infection and the high frequency of occult HBV infection in a blood bank in Argentina.
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Donantes de Sangre , ADN Viral/sangre , Genotipo , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/epidemiología , Adulto , Argentina/epidemiología , Femenino , Virus de la Hepatitis B/genética , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
The aim of this study was to analyze the prevalence of hepatitis C virus (HCV) genotypes in Córdoba province, Argentina, over a 12-year period and to study the changes at the molecular level. The HCV genotype was determined in 357 HCV-infected patients, and the phylogeny and demographic reconstruction for HCV-1 was assessed. A significant reduction in HCV-2 prevalence with respect to HCV-1 in Córdoba after 2003 was observed. These findings are consistent with the epidemiological changes observed in South America. Nevertheless, the consequences of these changes remain to be elucidated.
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Hepacivirus/genética , Hepatitis C/virología , Argentina/epidemiología , Genotipo , Hepacivirus/clasificación , Hepacivirus/aislamiento & purificación , Hepatitis C/epidemiología , Humanos , Filogenia , América del Sur/epidemiologíaRESUMEN
In Argentina, circulation of hepatitis E virus (HEV) genotype 3 has been described, producing sporadic cases of acute and chronic hepatitis. Limited information is available regarding HEV infection in children, so we aimed to investigate this virus in a pediatric population from the country. Serum samples from Argentine children (0-18 years old) (n = 213) were studied for IgG anti-HEV, IgM anti-HEV and RNA-HEV: 202 samples belonged to individuals attending health-care centers for routine check-ups, and 11 samples from patients with acute hepatitis of unknown etiology. Seropositivity for IgG anti-HEV was 1.49 % (3/202). One sample from an 18-years-old female patient with acute hepatitis tested positive for IgM anti-HEV detection, negative for IgG anti-HEV and RNA-HEV, but also positive for IgM anti-EBV. The HEV prevalence was low and showed circulation among children in central Argentina.
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Wastewater-based epidemiology (WBE) has gained prominence worldwide as a powerful tool in public health. This study aimed to monitor the circulation of Hepatitis E Virus (HEV) from wastewater samples collected during a six-year period and compare these results with clinical surveillance in the central region of Argentina. From 2017 to 2022, 1008 raw wastewater samples were analyzed, including four wastewater treatment plants from four cities (n=319), and 7 local neighborhood collector sewers in Córdoba city (n=689). Serum and/or stool samples from patients suspected of HEV infection were also analyzed (n=48). HEV molecular detection and viral load quantification were performed by real time RT-qPCR, and genetic characterization by two RT-Nested PCRs (targeting partial ORF-1 and ORF-2 genomic regions), sequencing and phylogenetic analysis. Fifty-three (5.3%) wastewater samples were RNA-HEV positive by real time RT-qPCR, with variations according to the location and year (0.0% - 21.6%). Out of these, ORF-2 genomic region was amplified in 20 samples (37.7%) and ORF-1 partial region in 12 (22.6%), and eighteen sequences were obtained. Throughout the study period, two (4.2%) HEV confirmed infections were reported, and one sequence was obtained. Phylogenetic analyses for both genomic regions showed that all the isolates were genotype HEV-3 clade abchijklm. Our study detected HEV in wastewater over a six-year period, despite a low number of clinical cases, emphasizing WBE as a valuable tool that complements clinical surveillance, by detecting pathogens' presence; identifying their transmission, circulation dynamics and excretion hotspots; and revealing changes in their genomic diversity.
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Virus de la Hepatitis E , Filogenia , Aguas Residuales , Argentina/epidemiología , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/aislamiento & purificación , Aguas Residuales/virología , Humanos , Hepatitis E/epidemiología , Hepatitis E/virología , Monitoreo Epidemiológico Basado en Aguas ResidualesRESUMEN
Hepatitis E virus (HEV) is an emerging cause of viral hepatitis and pigs are considered a reservoir for the virus. HEV genotype 3 (HEV-3) has been reported in pigs, environmental matrices, and sporadic human cases in Argentina. We aimed to investigate HEV circulation in pigs from central Argentina and to assess the virus presence in pork meat and food products. Four types of samples obtained or derived from pigs collected in Córdoba province (Argentina) between 2019 and 2022, were tested: 276 serum samples were analyzed for anti-HEV antibody detection; stool (n = 20), pork meat (n = 71), and salami (n = 76) samples were studied for RNA-HEV detection, followed by sequencing and phylogenetic analyses. The positivity rate for anti-HEV antibodies was 80.1% (221/276). Eleven fecal samples (11/20) tested positive for RNA-HEV, from animals under 120 days of age. Three samples could be sequenced, and phylogenetic analyses revealed that they belonged to HEV-3 clade abchijklm, clustering close to strains previously detected in wastewater from Córdoba. None of the muscle meat or salami samples tested positive. A high HEV circulation in pigs was found, showing that these animals may play a significant role in the viral maintenance in the region, becoming a potential risk to the exposed population. Despite not detecting RNA-HEV in pork meat and salami in our study, we cannot rule out the possibility of foodborne transmission in Córdoba province.
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Virus de la Hepatitis E , Hepatitis E , Productos de la Carne , Carne de Cerdo , Carne Roja , Enfermedades de los Porcinos , Humanos , Animales , Porcinos , Virus de la Hepatitis E/genética , Hepatitis E/epidemiología , Hepatitis E/veterinaria , Carne Roja/análisis , Argentina/epidemiología , Filogenia , Carne/análisis , Anticuerpos Antihepatitis , ARN Viral/genética , ARN Viral/análisis , Enfermedades de los Porcinos/epidemiologíaRESUMEN
Monitoring wastewater is an effective tool for tracking information on trends of enteric viral dissemination. This study aimed to perform molecular detection and genetic characterization of HAV in wastewater and to correlate the results with those obtained from clinical surveillance. Wastewater samples (n=811) of the second most populous city in Argentina were collected from the main wastewater treatment plant (BG-WWTP, n=261), and at 7 local neighborhood collector sewers (LNCS, n=550) during 2017-2022. Clinical samples of acute hepatitis A cases (HA, n=54) were also analyzed. HAV molecular detection was performed by real time RT-PCR, and genetic characterization by RT-Nested PCR, sequencing and phylogenetic analysis. RNA-HAV was detected in sewage samples throughout the entire period studied, and detection frequencies varied according to the location and year (2.9% - 56.5%). In BG-WWTP, 23% of the samples were RNA-HAV+. The highest detection rates were in 2017 (30.0%), 2018 (41.7%) and 2022 (56.5%), which coincides with the highest number of HA cases reported. Twenty-eight (28) sequences were obtained (from clinical and sewage samples), and all were genotype IA. Two monophyletic clusters were identified: one that grouped clinical and wastewater samples from 2017-2018, and another with specimens from 2022, evidencing that environmental surveillance might constitute a replica of viral circulation in the population. These findings evidence that WBE, in a centralized and decentralized sewage monitoring, might be an effective strategy to track HAV circulation trends over time, contributing to the knowledge of HAV in the new post-vaccination epidemiological scenarios in Argentina and in Latin America.
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Virus de la Hepatitis A , Hepatitis A , Humanos , Virus de la Hepatitis A/genética , Aguas Residuales , Aguas del Alcantarillado , Filogenia , Hepatitis A/epidemiología , ARN , Reacción en Cadena en Tiempo Real de la Polimerasa , ARN ViralRESUMEN
Rio Negro virus (RNV) (Venezuelan equine encephalitis subtype VI) circulates only in Argentina; in northern provinces, isolates have been obtained from mosquitoes and rodents since 1980 and have been associated with acute febrile illness in humans. However, no studies of RNV have been performed in the central area of the country. We carried out molecular and serological detection of RNV in Córdoba, a province of the central part of the country, in mosquitoes and humans, respectively. One mosquito pool tested positive for alphavirus RNA by reverse transcriptase-nested polymerase chain reaction (RT-nested PCR). Subsequent sequencing determined that this alphavirus grouped with RNV. Serological studies detected antibodies to RNV in one human serum sample, which was obtained during the same period that RNV was detected using the aforementioned molecular methods. This is the first report of RNV circulation in the central area of Argentina, indicating an expansion of its original distribution. These results highlight the importance of strengthening surveillance procedures in endemic areas, as well as in new regions where RNV may emerge.
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Culicidae/virología , Virus de la Encefalitis Equina Venezolana/genética , Encefalomielitis Equina Venezolana/virología , Insectos Vectores/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Antivirales/sangre , Argentina/epidemiología , Niño , Preescolar , Virus de la Encefalitis Equina Venezolana/inmunología , Virus de la Encefalitis Equina Venezolana/aislamiento & purificación , Encefalomielitis Equina Venezolana/diagnóstico , Encefalomielitis Equina Venezolana/epidemiología , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto JovenRESUMEN
In the United States (U.S.), a hepatitis E virus (HEV) seroprevalence between 6 and 21% has been described, with a decreasing trend. We aimed to investigate HEV infection in the U.S. population from 2009 to 2016, and examine the differences in seroprevalence using different assays. We used data from the National Health and Nutrition Examination Survey (NHANES-CDC) to estimate HEV seroprevalence and analyze demographic variables related to the infection. Additionally, we compared 4 serological tests used. The estimated HEV seroprevalence between 2009-2016 was 6.1% (95% CI: 5.6%-7.0%) for IgG and 1.02% (0.8%-1.2%) for IgM. Higher HEV IgG prevalences were found in older people, females, non-Hispanic Asians and those born outside of the U.S. The in-house immunoassay and the Wantai HEV-IgG ELISA presented the highest sensitivity values in the tested population. The highest specificity values corresponded to the DSI-EIA-ANTI-HEV-IgG assay. The kappa statistical values showed concordances no greater than 0.64 between the assays. HEV prevalence in our study was similar to previously reported, and a decline in the prevalence was observed through the NHANES assessments (from 1988 to 2016). The sensitivity and specificity of the assays varied widely, making comparisons difficult and highlighting the need to develop a gold standard assay.
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Virus de la Hepatitis E , Hepatitis E , Anciano , Femenino , Anticuerpos Antihepatitis , Humanos , Inmunoglobulina G , Inmunoglobulina M , Encuestas Nutricionales , Factores de Riesgo , Estudios Seroepidemiológicos , Estados Unidos/epidemiologíaRESUMEN
SARS-CoV-2 variants of concern (VOC) and interest (VOI) present mutations in reference to the original virus, being more transmissible. We implemented a rapid strategy for the screening of SARS-CoV-2 VOC/VOIs using real time RT-PCR and performed monitoring and surveillance of the variants in our region. Consecutive real-time RT-PCRs for detection of the relevant mutations/deletions present in the Spike protein in VOC/VOIs (TaqMan™ SARS-CoV-2 Mutation Panel, Applied Biosystems) were implemented. A total of 6,640 SARS-CoV-2 RNA samples (Cts < 30) from infected individuals in Central Argentina during 2021 were analyzed using different algorithms that were gradually adapted to the changing scenarios of local variant circulation. The strategy developed allowed the early detection and the identification of VOC/VOIs that circulated through the year, with a 100% of concordance with the WGS. The analyses of the samples showed introductions of VOCs Alpha and Gamma in February and March 2021, respectively. Gamma showed an exponential increase, with a peak of detection in July (72%), being responsible of the second wave of COVID19 in Argentina. Since VOC Delta entered into the region, it increased gradually, together with VOI Lambda, replacing VOC Gamma, until being the main variant (84.9%) on November. By December, these variants were replaced by the emergent VOC Omicron in a term of 2 weeks, producing the third wave. We report a useful tool for VOC/VOI detection, capable to quickly and cost-effectively monitor currently recognized variants in resource-limited settings, which allowed to track the recent expansion of Omicron in our region, and contributed to the implementation of public health measures to control the disease spread.
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Although the nasopharyngeal swab (NPS) is considered the gold standard for the diagnosis of the SARS-CoV-2 infection, the Nasal Mid-Turbinate swab (NMTS) is often used due to its higher tolerance among patients. We compared the diagnostic performance of the NPS and the NMTS for the Panbio™ COVID-19 antigen-detecting rapid diagnostic test (Ag-RDT). Two hundred and forty-three individuals were swabbed three times by healthcare professionals: a NMTS and a NPS specimen for the Ag-RDT and an oropharyngeal swab for real time RT-PCR. Forty-nine participants were RNA-SARS-CoV-2 positive by real time RT-PCR: 45 and 40 were positive by the Ag-RDT with NPS and NMTS, respectively. The overall sensitivity and specificity were 91.8% (95% CI: 83.2-100.0) and 99.5% (95% CI: 98.2-100.0) for Ag-RDT with NPS, and 81.6% (95% CI: 69.8-93.5) and 100.0% (95% CI: 99.7-100.0) for the Ag-RDT with NMTS. The Cohen's kappa index was 0.92 (95% CI: 0.85-0.98). Among asymptomatic individuals, the Ag-RDT with both sampling techniques showed a high sensitivity [100.0% (95% CI: 95.5-100.0) with NPS; 90.9% (95% CI: 69.4-100.0) with NMTS], while the performance of the test decreased in samples with Ct≥ 30 and in patients tested after the first 7 days from symptom onset. Although the NMTS yielded a lower sensitivity compared to NPS, it might be considered a reliable alternative, as it presents greater adherence among patients, enabling scaling of antigen testing strategies, particularly in countries with under-resourced health systems.
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COVID-19 , Antígenos Virales , COVID-19/diagnóstico , Humanos , SARS-CoV-2 , Sensibilidad y Especificidad , Cornetes NasalesRESUMEN
BACKGROUND: The hepatitis E virus (HEV) causes acute hepatitis, which can progress to chronicity in immunosuppressed patients. It is transmitted mainly by the fecal-oral or zoonotic routes, but there is current evidence that it can be transmitted by blood transfusions. The objective of the study was to investigate HEV infections in blood donors in Argentina, within the framework of a hemovigilance program. METHODS: A total of 547 samples from Argentinean blood donors, collected in 2016, 2019 and 2020 was studied for IgG and IgM anti-HEV by ELISA (Diapro) and RNA HEV by RT-real time PCR and RT-Nested-PCR. RESULTS: The prevalence of IgG anti-HEV was 3.47% (19/547). No significant differences were registered according to the year studied, sex or age. The presence of RNA HEV was observed in 0.18% (1/547) of the donors studied without serological evidence of infection. CONCLUSIONS: This is the first molecular detection in blood donors from Argentina, showing a molecular prevalence within the range described for RNA-HEV in blood donors from other non-endemic countries, in which immunocompetent RNA-HEV positive donors without serological evidence of infection were identified. The presence of viraemic donors could imply transfusion transmission, which deserves further attention and study.
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Virus de la Hepatitis E , Hepatitis E , Argentina/epidemiología , Donantes de Sangre , Hepatitis E/epidemiología , Virus de la Hepatitis E/genética , Humanos , Inmunoglobulina G , Inmunoglobulina M , ARN , ARN Viral/genética , Estudios SeroepidemiológicosRESUMEN
Monitoring wastewater for the traces of viruses allows effective surveillance of entire communities, including symptomatic and asymptomatic infected individuals, providing information on whether a specific pathogen is circulating in a population. In the context of the COVID-19 pandemic, 261 wastewater samples from six communities of the province of Córdoba, Argentina were analyzed. From mid-May 2020 to the end of August 2021, raw sewage samples were collected from the central network pipe that enters into the Wastewater Treatment Plants (WWTP) in Córdoba city and five communities in the Punilla Valley. SARS-CoV-2 was concentrated by using the polyethylene glycol-6000 precipitation method. Viral genomes were extracted from concentrated samples, and N- and E-SARS-CoV-2 genes were detected by using real time RT-PCR. Wastewater samples that resulted positive for SARS-CoV-2 genome detection were subjected to viral variants of concern (VOCs) identification by real time RT-PCR. Overall, just by using the identification of the N gene or E gene, the rates of viral genome detection were 43.4% (86/198) and 51.5% (102/198) respectively, and by using both methodologies (positivity criterion: detection of N and / or E gene), the detection rate was 71.2% (141/198). Thereby, the optimal strategy to study the SARS-CoV-2 genome in wastewater would be the use of the combined detection of both genes. Detection of SARS-CoV-2 variants in wastewater reflected their circulation in the community, showing no VOCs detection in the first COVID-19 wave and their co-circulation with Gamma, Alpha and Delta VOCs during 2021. Therefore, SARS-CoV-2 Wastewater Based Epidemiology (WBE) described the introduction, permanence and/or the co-circulation of viral variants in the community. In geographical areas with a stable population, SARS-CoV-2 WBE could be used as an early warning sign of new COVID-19 cases, whereas in localities with a low number of inhabitants and high tourist influx, WBE may only be useful to reflect the circulation of the virus in the community. Overall, the monitoring of SARS-CoV-2 in wastewater can become a silent sentinel of the trend of viral circulation in the community, providing supplementary information for clinical surveillance to support public health measures.
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COVID-19 , SARS-CoV-2 , Argentina/epidemiología , COVID-19/epidemiología , Humanos , Pandemias , ARN Viral , Aguas Residuales , Monitoreo Epidemiológico Basado en Aguas ResidualesRESUMEN
BACKGROUND: The current COVID-19 pandemic has overloaded the diagnostic capacity of laboratories by the gold standard method rRT-PCR. This disease has a high spread rate and almost a quarter of infected individuals never develop symptoms. In this scenario, active surveillance is crucial to stop the virus propagation. METHODS: Between July 2020 and April 2021, 11,580 oropharyngeal swab samples collected in closed and semi-closed institutions were processed for SARS-CoV-2 detection in pools, implementing this strategy for the first time in Córdoba, Argentina. Five-sample pools were constituted before nucleic acid extraction and amplification by rRT-PCR. Comparative analysis of cycle threshold (Ct) values from positive pools and individual samples along with a cost-benefit report of the whole performance of the results was performed. RESULTS: From 2,314 5-sample pools tested, 158 were classified as positive (6.8%), 2,024 as negative (87.5%), and 132 were categorized as indeterminate (5.7%). The Ct value shift due to sample dilution showed an increase in Ct of 2.6±1.53 cycles for N gene and 2.6±1.78 for ORF1ab gene. Overall, 290 pools were disassembled and 1,450 swabs were analyzed individually. This strategy allowed correctly identifying 99.8% of the samples as positive (7.6%) or negative (92.2%), avoiding the execution of 7,806 rRT-PCR reactions which represents a cost saving of 67.5%. CONCLUSION: This study demonstrates the feasibility of pooling samples to increase the number of tests performed, helping to maximize molecular diagnostic resources and reducing the work overload of specialized personnel during active surveillance of the COVID-19 pandemic.
Asunto(s)
COVID-19 , Pandemias , COVID-19/diagnóstico , COVID-19/epidemiología , Humanos , ARN Viral/genética , SARS-CoV-2/genética , Sensibilidad y Especificidad , Manejo de Especímenes/métodos , Espera VigilanteRESUMEN
Foodborne viruses have been recognized as a growing concern to the food industry and a serious public health problem. Hepatitis A virus (HAV) is responsible for the majority of viral outbreaks of food origin worldwide, while hepatitis E virus (HEV) has also been gaining prominence as a foodborne viral agent in the last years, due to its zoonotic transmission through the consumption of uncooked or undercooked infected meat or derivatives. However, there is a lack of scientific reports that gather all the updated information about HAV and HEV as foodborne viruses. A search of all scientific articles about HAV and HEV in food until March 2020 was carried out, using the keywords "HAV", "HEV", "foodborne", "outbreak" and "detection in food". Foodborne outbreaks due to HAV have been reported since 1956, mainly in the USA, and in Europe in recent years, where the number of outbreaks has been increasing throughout time, and nowadays it has become the continent with the highest foodborne HAV outbreak report. Investigation and detection of HAV in food is more recent, and the first detections were performed in the 1990s decade, most of them carried out on seafood, first, and frozen food, later. On the other hand, HEV has been mainly looked for and detected in food derived from reservoir animals, such as meat, sausages and pate of pigs and wild boars. For this virus, only isolated cases and small outbreaks of foodborne transmission have been recorded, most of them in industrialized countries, due to HEV genotype 3 or 4. Virus detection in food matrices requires special processing of the food matrix, followed by RNA detection by molecular techniques. For HAV, a real-time PCR has been agreed as the standard method for virus detection in food; in the case of HEV, a consensus assay for its detection in food has not been reached yet. Our investigation shows that there is still little data about HAV and HEV prevalence and frequency of contamination in food, prevalent viral strains, and sources of contamination, mainly in developing countries, where there is no research and legislation in this regard. Studies on these issues are needed to get a better understanding of foodborne viruses, their maintenance and their potential to cause diseases.