INTRODUCTION: A decline in hepatitis D virus (HDV) occurrence was described in Europe and Asia. We estimated HDV prevalence in the Brazilian Amazon following hepatitis B vaccination. METHODS: This is a cross-sectional survey of HDV measured by total antibodies to HDV (anti-HD T). RESULTS: HDV prevalence was 41.9% whiting HBsAg carries and was associated with age (PR = 1.96; 95% CI 1.12-3.42; p = 0.01), hepatitis B virus (HBV) infection (PR = 4.38; 95% CI 3.12-6.13; p < 0.001), and clinical hepatitis (PR =1.44; 95% CI 1.03-2.00; p = 0.03). Risk factors were related to HDV biology, clinical or demographic aspects such as underlying HBV infection, clinical hepatitis and age. CONCLUSIONS: Our study demonstrated that HDV infection continues to be an important health issue in the Brazilian Amazon and that the implementation of the HBV vaccination in rural Lábrea had little or no impact on the spread of HDV. This shows that HDV has not yet disappeared from HBV hyperendemic areas and reminding that it is far from being a vanishing disease in the Amazon basin.

Abstract. Individuals from three isolated, rural communities in the western Brazilian Amazon were evaluated for serological markers of hepatitis B virus (HBV) infection, HBV genotype, and the presence of risk factors for infection and transmission. Of the 225 individuals studied, 79.1% had serological evidence of HBV infection; 10.2% individuals were chronic carriers for HBV surface antigen (HBsAg-positive). Analysis of risk factors indicates that HBV is transmitted mainly horizontally within the family from a chronic "active" carrier for hepatitis B "e" antigen (HBeAgpositive), though a strong possibility of vertical transmission remains. The predominance of HBV genotype F, with a higher genomic similarity between the isolates, indicated a relatively recent introduction of HBV, from a common source, to the area. This study sheds light on the HBV epidemiology in the Brazilian Amazon region and highlights the need for greater emphasis on HBV control and immunization programs.

Abstract. The purpose of this study was to correlate morphologic and hemodynamic Doppler ultrasound findings as indicators of the degree of inflammation and fibrosis and to diagnose chronic vital hepatitis complications and progression. A prospective, descriptive study of a case series was conducted that analyzed Doppler ultrasound images of the liver and portal system and used the portal vein congestion index, hepatic and splenic artery impedance indices, and the liver vascular index. Of 50 patients positive for antibodies against hepatitis C virus, morphologic changes highlighted increased hepatic parenchyma echogenicity in 24%, and increased gall blander echogenicity and wall thickness in 4%. The most common hemodynamic changes observed were reduced flow velocity in the portal vein trunk in 26%, congestion index changes in 12%, liver vascular index changes in 16%, and splenic and hepatic artery impedance index changes in 14%. These indices were shown to be associated with alanine aminotransferase levels, which suggested that they are important liver damage indicators in the early phase of infection with hepatitis C virus.