A high prevalence of occult hepatitis B (OHB) genotype H infections has been observed in the native Mexican Nahua population. In addition, a low incidence of hepatitis B virus (HBV)-associated hepatocellular carcinoma has been described in Mexico. The immune response to infection among OHB-infected patients has been poorly evaluated in vivo. Therefore, we assessed the expression profiles of 23 cytokines in OHB genotype H-infected Nahua patients. A total of 41 sera samples from natives of the Nahua community were retrospectively analysed. Based on their HBV antibody profiles, patients were stratified into two groups: OHB patients (n = 21) and patients that had recovered from HBV infection (n = 20). Herein, we report distinctive cytokines profiles in OHB-infected individuals. Compared to healthy controls (n = 20) and patients who resolved HBV infection, OHB-infected patients displayed an increase in interleukin (IL)-2 secretion in addition to a characteristic inflammation profile (decrease in IL-8 and tumour necrosis factor-alpha levels and increased levels of tumour growth factor-beta). IL-15 and interferon-gamma levels were reduced in OHB-infected individuals when compared to those patients who resolved HBV infection. In contrast, OHB patients showed an increase in monocyte chemoattractant protein (MCP)-1 and MCP-2 compared to healthy controls and patients who resolved HBV infection. These findings suggest that cytokine expression can influence the severity of OHB disease and could lead to new investigation into the treatment of liver and other infectious diseases.

The main etiology of liver disease in Mexico is alcohol and viral hepatitis. The aim of the present study was to analyze the current epidemiology of viral hepatitis in Mexico. From 2000 to 2007 the Ministry of Health reported 192 588 cases of hepatitis, 79% HAV, 3.3% HBV, 6% HCV, and 12% without a specific etiologic factor. Due to high endemic areas for HBV infection in native Mexican population, limitations in the diagnostic sensitivity and specificity of the serological immunoassays used to date and presence of occult hepatitis B in the country, the real prevalence of HBV infection could be even higher than HCV in Mexico. Hepatitis E virus in cirrhotic patients and in porcine farms could at least partially explain the cases of hepatitis that are diagnosed without a specific etiologic agent. Specific strategies to establish control regulations against viral hepatitis infections in Mexico are proposed.

Las hepatitis virales son una de las causas principales de daño hepático en México. En este estudio se analiza el estado actual de las hepatitis virales en México. La Secretaría de Salud informa un total de 192 588 casos de hepatitis virales entre 2000 y 2007. De éstos, 79% corresponden aVHA, 3.3% aVHB, 6% a VHC y 11.7% a casos sin agente etiológico descrito. No obstante, el VHB se podría estar subdiagnosticando, ya que hay zonas de alta endemia en poblaciones indígenas, existen limitaciones en la sensibilidad y especificidad de las pruebas inmunológicas y podría ser común la hepatitis B oculta. ElVHE podría ser uno de los agentes etiológicos de aquellos casos que carecen de un agente etiológico conocido. Se proponen estrategias específicas para el control de las hepatitis virales tendientes a disminuir el número de casos.

The main etiology of liver disease in Mexico is alcohol and viral hepatitis. The aim of the present study was to analyze the current epidemiology of viral hepatitis in Mexico. From 2000 to 2007 the Ministry of Health reported 192 588 cases of hepatitis, 79% HAV, 3.3% HBV, 6% HCV, and 12% without a specific etiologic factor. Due to high endemic areas for HBV infection in native Mexican population, limitations in the diagnostic sensitivity and specificity of the serological immunoassays used to date and presence of occult hepatitis B in the country, the real prevalence of HBV infection could be even higher than HCV in Mexico. Hepatitis E virus in cirrhotic patients and in porcine farms could at least partially explain the cases of hepatitis that are diagnosed without a specific etiologic agent. Specific strategies to establish control regulations against viral hepatitis infections in Mexico are proposed.

Las hepatitis virales son una de las causas principales de daño hepático en México. En este estudio se analiza el estado actual de las hepatitis virales en México. La Secretaría de Salud informa un total de 192 588 casos de hepatitis virales entre 2000 y 2007. De éstos, 79% corresponden aVHA, 3.3% aVHB, 6% a VHC y 11.7% a casos sin agente etiológico descrito. No obstante, el VHB se podría estar subdiagnosticando, ya que hay zonas de alta endemia en poblaciones indígenas, existen limitaciones en la sensibilidad y especificidad de las pruebas inmunológicas y podría ser común la hepatitis B oculta. ElVHE podría ser uno de los agentes etiológicos de aquellos casos que carecen de un agente etiológico conocido. Se proponen estrategias específicas para el control de las hepatitis virales tendientes a disminuir el número de casos.