Optimization of the molecular diagnosis of the acute hepatitis E virus infection

Integrated hepatitis e virus monitoring in central Argentina: a six-year analysis of clinical surveillance and wastewater-based epidemiology

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.

Systematic Evaluation of Guidelines for the Diagnosis and Treatment of Hepatitis E Virus Infection

Background and Aims

The hepatitis E virus (HEV) is a zoonotic disease, and infection with HEV in humans primarily causes acute infections and can progress to chronic manifestation in immunocompromised individuals. Over the past decade, guidelines for diagnosing and treating HEV infection have been developed. This study aimed to systematically assess the quality of current guidelines for diagnosing and treating HEV infection, and we analyzed the differences in guideline quality and primary recommendations and explored possible reasons for these differences.

Methods

Guidelines published between 2013 and 2022 were searched, and studies were identified using selection criteria. The study assessed the quality of the included guidelines using the Appraisal of Guidelines for Research and Evaluation tool, extracted the primary recommendations in the guidelines, determined the highest level of evidence supporting the recommendations, and reclassified the evidence using the Oxford Centre for Evidence-Based Medicine grading system.

Results

Seven guidelines were included in the final analysis. The quality of the guidelines varied widely. The discrepancies may have been caused by the lack of external experts, the failure to consider influencing factors in guideline application, and the lack of consideration of the public's opinion. Analysis of the heterogeneity in primary recommendations revealed differences in algorithms for managing chronic HEV infection, the dosage of ribavirin, and a low level of evidence supporting the primary recommendations.

Conclusions

Guideline quality and primary recommendations vary considerably. Refinement by guideline developers and researchers would facilitate updating and applying guidelines for diagnosing and treating HEV infection.

Hepatitis E virus infections

Hepatitis E virus (HEV) infection is now endemic worldwide. Most patients with acute infection recover uneventfully. Outbreaks and sporadic cases, particularly in high-risk individuals are emerging increasingly. The patients with risk factors like pregnancy and pre-existing chronic liver disease, present with or progress rapidly to severe disease. Immuno-suppression in post-transplant patients is an additional risk factor. Standardized FDA-approved diagnostic tests are the need of the hour. Further studies are needed to establish guideline-based treatment regimen and outbreak preparedness for HEV to decrease global morbidity, mortality, and healthcare burden. Policies for screening donors and transplant cases are required.

Correlation of hepatitis E and rat hepatitis E viruses urban wastewater monitoring and clinical cases

BACKGROUND

Wastewater pathogen monitoring is useful for surveillance of enteric pathogens. Information about the presence of Paslahepevirus balayani (HEV) and emergent Rocahepevirus ratti (RHEV) in untreated water and their correlation with clinical cases is scarce. Aim To longitudinally monitor HEV and RHEV in wastewater and to evaluate their possible correlation with human cases.

METHODS

This study was carried out in the city of Cordoba (southern Spain) from March 2021 to March 2023. HEV and RHEV occurrence were evaluated by PCR in three sample types: i) sera from patients with acute hepatitis attended at the reference hospital, ii) liver and faeces from urban rodents, and iii) grab sewage samples collected weekly from the municipal wastewater treatment plant.

RESULTS

We analysed 106 untreated wastewater samples, 304 individuals with acute hepatitis, and 20 rodents. HEV and RHEV were detected in only one (0.9 %) and almost all samples (94.3 %) of wastewater samples, respectively. A total of 22 cases of acute HEV infection (7.2 %) and two cases of RHEV (0.7 %) were detected from all acute hepatitis cases observed. Only RHEV was found in rodents, with a positive frequency of 55 %. The presence of HEV in wastewater coincided with the detection of one case in which the same HEV genotype was isolated. A concentration of HEV clinical cases between June and July of 2022 was observed but not detected in water. Both RHEV clinical cases were detected in summer 2022, but no correlation was found with wastewater detection.

CONCLUSIONS

Our study shows that there is no correlation between clinical cases and wastewater detection of HEV or RHEV.

Rocahepevirus ratti as an Emerging Cause of Acute Hepatitis Worldwide

The hepatitis E virus (HEV) is a widespread human infection that causes mainly acute infection and can evolve to a chronic manifestation in immunocompromised individuals. In addition to the common strains of hepatitis E virus (HEV-A), known as Paslahepevirus balayani, pathogenic to humans, a genetically highly divergent rat origin hepevirus (RHEV) can cause hepatitis possessing a potential risk of cross-species infection and zoonotic transmission. Rocahepevirus ratti, formerly known as Orthohepevirus C, is a single-stranded RNA virus, recently reassigned to Rocahepevirus genus in the Hepeviridae family, including genotypes C1 and C2. RHEV primarily infects rats but has been identified as a rodent zoonotic virus capable of infecting humans through the consumption of contaminated food or water, causing both acute and chronic hepatitis cases in both animals and humans. This review compiles data concluding that 60% (295/489) of RHEV infections are found in Asia, being the continent with the highest zoonotic and transmission potential. Asia not only has the most animal cases but also 16 out of 21 human infections worldwide. Europe follows with 26% (128/489) of RHEV infections in animals, resulting in four human cases out of twenty-one globally. Phylogenetic analysis and genomic sequencing will be employed to gather global data, determine epidemiology, and assess geographical distribution. This information will enhance diagnostic accuracy, pathogenesis understanding, and help prevent cross-species transmission, particularly to humans.