Hepatitis E Virus Genotype 3 among Hemodialysis Patients in Mexico: First Identification of Chronic Infection.

The global distribution of hepatitis E virus (HEV) is attributed to its capacity to spread through several routes of transmission; hemodialysis has gained increased amounts of attention in recent years. Although Mexico is considered a hyperendemic region for hepatitis E, no HEV surveillance is performed in the country. The frequency of HEV in hemodialysis (HD) patients has not been determined. Herein, we conducted a cross-sectional single-center analytical study including 67 serum samples from HD patients. Anti-HEV IgG and IgM antibodies and the viral genome were determined; partial regions within the HEV genome were sequenced for further phylogenetic analysis. Globally, 14.9% of the tested patients exhibited reactivity for IgG antibodies against HEV, and none showed reactivity to IgM. A total of 5.9% of the samples showed HEV genome amplification, and sequencing confirmed the identity of genotype 3; subsequent analysis of positive cases revealed two acute cases and chronic hepatitis E infection in one patient. Notably, the chronic patient was negative for anti-HEV IgG antibodies. Our findings highlight the importance of viral genome testing in HD patients and the need to establish guidelines for HEV detection in Mexico.

IL-18 discriminates highly frequent hepatitis E virus positive from negative blood donors in Mexico.

INTRODUCTION AND OBJECTIVES: Hepatitis E virus (HEV) is not routinely screened in blood banks in low- and middle-income countries, and no specific biomarkers of exposure to this virus have yet been identified. We aimed to identify HEV seropositivity and detect virus RNA among blood donors from Mexico to further correlate risk factors related to infection and levels of interleukin-18 (IL-18) and interferon-gamma (IFN-γ) as potential biomarkers. MATERIALS AND METHODS: This cross-sectional, single-center study included 691 serum samples of blood donors obtained in 2019. Anti-HEV IgG and IgM antibodies were detected in sera and the viral genome was screened in pooled samples. A statistical comparison of risk factors for infection, demographic and clinical features was performed; IL-18 and IFN- Î³ values were tested in sera. RESULTS: Of all the individuals, 9.4% were positive for anti-HEV antibodies and viral RNA detection was confirmed in one of the pools positive for anti-HEV. From the analysis of risk factors, age and having pets were statistically significant for anti-HEV antibody detection. Seropositive samples showed significantly higher IL-18 concentrations relative to samples from seronegative donors. Interestingly, IL-18 values were similar when HEV seropositive samples were compared to samples from clinically acute previously confirmed HEV patients. CONCLUSIONS: Our findings highlight the need to follow up on HEV in blood banks in Mexico and underscore that IL-18 could represent a biomarker of HEV exposure.

Sobre la hepatitis aguda grave de etiología desconocida: la situación en México / About severe acute hepatitis of unknown etiology: the situation in Mexico

Introducción: en México, las hepatitis virales son de notificación epidemiológica obligatoria, pero no existe un sistema especial de vigilancia. La información disponible se limita a la distribución por edad y sexo. Ante la alerta de casos de hepatitis aguda grave de etiología desconocida, en la Unión Europea el Consejo Nacional de Vigilancia Epidemiológica (CONAVE) alertó al Sistema Nacional de Salud (SNS) para la atención y vigilancia de estos casos. Desarrollo: la hipótesis más convincente sobre la etiología está relacionada con una respuesta inmunitaria exacerbada que es mediada por superantígenos relacionados con la proteína espiga del SARS-CoV-2, activados por una infección por adenovirus que desencadena una respuesta de linfocitos T que provoca apoptosis de hepatocitos. Con base en la presentación clínica (niños menores de 16 años, con diarrea, dolor abdominal, ictericia, vómito e hipertransaminasemia) se han diseñado definiciones operacionales para su identificación y notificación al Sistema Nacional de Vigilancia Epidemiológica (SINAVE). Hasta junio del 2022, se han identificado 56 casos en México. Conclusiones: este brote de hepatitis representa un reto para el SINAVE. Es necesario incluir la identificación de adenovirus en el algoritmo diagnóstico de enfermedad respiratoria viral, implementar un sistema especial de vigilancia epidemiológica de hepatitis virales y sensibilizar a los profesionales sanitarios en el tema.

Introduction: In Mexico viral hepatitis requires mandatory epidemiological notification, but there is no special surveillance system. Available information is limited to distribution of cases by age and sex. Given the alert of cases of severe acute hepatitis of unknown etiology in the European Union, the National Council for Epidemiological Surveillance (Consejo Nacional de Vigilancia Epidemiológica) alerted the entire National Health System to care for and monitor these cases in Mexico. Development: The most convincing hypothesis is an exacerbated immune response mediated by superantigens related to the spike protein of SARS-CoV-2, activated by adenovirus infection that ends in a response of T lymphocytes that causes apoptosis of hepatocytes. Based on clinical presentation (children under 16 years of age, with diarrhoea, abdominal pain, jaundice, vomiting and increase in transaminases) the operational case definitions have been designed for their timely identification and notification to the National System of Epidemiological Surveillance (Sistema Nacional de Vigilancia Epidemiológica). Until June 2022, 56 cases have been identified in Mexico. Conclusions: This hepatitis outbreak represents a challenge for the National System of Epidemiological Surveillance. It is necessary to include the identification of adenovirus in the diagnostic algorithm for viral respiratory disease, to implement a special epidemiological surveillance system for viral hepatitis, and to sensitize health professionals on this subject.

Spatial and Temporal Distribution of Hepatitis A Virus and Hepatitis E Virus Among Children with Acute Hepatitis in Mexico.

Hepatitis A virus (HAV) and hepatitis E virus (HEV) cause most of the global burden of viral hepatitis. Geographical and seasonal patterns contribute to the epidemiological status of infectious diseases. The extent of these features in the setting of HAV and HEV infections has not been analyzed in detail. This point is important in highly endemic countries of both viruses, where the pediatric population is at high risk of contracting these infections. A comparison between the frequency of antibodies to HAV and HEV and viral RNA detection in serum samples from pediatric patients with acute hepatitis from South and West Mexico was performed. All samples were positive for HAV mono-infection, which was most frequently detected in the metropolitan areas during the rainy season in the South (90%) and all year round in the West (42%). No HEV mono-infection was detected in the studied regions. A 58% frequency for HAV/HEV co-infection was found in the West, predominantly in the metropolitan areas during the rainy months. A 10% frequency for co-infection broadly distributed in the South throughout the year was also found. Our findings underscore that the distribution of HAV and HEV infections varies through the year and differs among Mexico's distinct geographical regions.

COVID-19 and gastrointestinal symptoms in Mexico, a systematic review: does location matter?

BACKGROUND: Covid-19 in Mexico is on the rise in different parts of the country. We aimed to study the symptoms and comorbidities that associate with this pandemic in 3 different regions of Mexico. METHODS: We analyzed data from SARS-CoV-2 positive patients evaluated at healthcare centers and hospitals of Mexico (n = 1607) including Northwest Mexico (Sinaloa state), Southeast Mexico (Veracruz state) and West Mexico (Jalisco state) between March 1 and July 30, 2020. Mexico consists of a total population that exceeds 128 million. Demographics, comorbidities and clinical symptoms were collected. Statistical descriptive analysis and correlation analyses of symptoms, comorbidities and mortality were performed. RESULTS: A total of 1607 hospitalized patients positive for COVID-19 across all 3 regions of Mexico were included. The average age was 54.6 years and 60.4% were male. A mortality rate of 33.1% was observed. The most common comorbidities were hypertension (43.2%), obesity (30.3%) and diabetes (31.4%). Hypertension was more frequent in West (45%), followed by Northwest (37%) and Southeast Mexico (29%). Obesity was around 30% in Northwest and West whereas an 18% was reported in Southeast. Diabetes was most common in West (34%) followed by Northwest (22%) and Southeast (13%). This might be related to the highest mortality rate in Northwest (31%) and West (37%) when compared to Southeast. Most common symptoms in our overall cohort were fever (80.8%), cough (79.8%), headache (66%), dyspnea (71.1%), myalgia (53.8%), joints pain (50.8%) and odynophagia (34.8%). Diarrhea was the main gastrointestinal (GI) symptom (21.3%), followed by abdominal pain (18%), and nausea/ vomiting (4.5%). Diarrhea and abdominal pain were more common in West (23.1 and 21%), followed by Southeast (17.8, and 9.8%) and Northwest (11.4 and 3.1%). CONCLUSION: Our study showed a high mortality rate likely related to high frequencies of comorbidities (hypertension, obesity and diabetes). Mortality was different across regions. These discrepancies might be related to the differences in the frequencies of comorbidities, and partially attributed to differences in socio-economic conditions and quality of care. Thus, our findings stress the need for improved strategies to get better outcomes in our population.

Hepatitis E Virus Genotype 1 and Hepatitis A Virus Dual Infection in Pediatric Patients with a Low Socioeconomic Status from Mexico.

OBJECTIVE: We aimed to detect and characterize hepatitis E virus (HEV) RNA in sera samples from a pediatric population infected with the hepatitis A virus (HAV) exhibiting acute hepatitis and to correlate the infection status with the clinical outcome. METHODS: Seventy-five ELISA-positive samples from children containing anti-HAV and anti-HEV IgM were used to amplify and characterize partial regions within HEV ORF2. A statistical comparison of clinical data between HEV IgM-positive/HEV RNA-positive patients and HEV IgM-positive/HEV RNA-negative patients was performed. RESULTS: Thirteen out of 75 IgM-positive samples provided amplification of discrete regions of the HEV genome. Nested RT-PCR-based detection and subsequent sequencing of 5 samples confirmed the identity of HEV genotype 1 (G1), which had not been previously reported in Mexico. Though not significant, a trend towards exacerbated clinical manifestations was found in HEV RNA-positive patients relative to HEV RNA-negative patients. CONCLUSIONS: An elevated rate of G1 RNA was detected. Hepatitis E seems to be a neglected disease in Mexico and epidemic strains of HEV are likely to play a role as causative agents of acute hepatitis in highly exposed children. Although HAV is endemic in Mexico, an HEV-RNA detection rate of 17% in co-infected samples shows the need for screening for HEV as a part of future vaccination strategies.