Prevalence of this virus was found to be significantly higher in individuals with past exposure to hepatitis E virus and having moderately raised alanine aminotransferase levels.
A novel cluster of five ferret hepatitis E virus (HEV) strains was detected from nine laboratory ferrets (Mustela putorius furo) imported from a ferret farm in the U.S. Our detection of ferret HEV RNA and anti-HEV antibodies, and alanine aminotransferase (ALT) value assessment indicated that all of the 9 ferrets were infected with ferret HEV, and that the infection exhibited three patterns: sub-clinical infection (n=2), acute hepatitis (n=6) and persistent infection (n=1).
There were no differences in mortality (27% vs. 26%, OR 1.1, 95% CI 0.28-4.1), age (P = 0.9), bilirubin (P = 0.5), alanine aminotransferase (P = 0.06) albumin (P = 0.5) or international normalised ratio (P = 0.6) in patients with and without hepatitis E infection.
In the cohort of patients with acute symptomatic HE (n = 47), men outnumbered women (40:7), the patients were in older middle age (mean, 60.57 years), and they had elevated median values of total bilirubin (6.67 mg/dL), alanine aminotransferase (2288.82 U/L), aspartate aminotransferase (1251.76 U/L), gamma-glutamyl transferase (360.53 U/L), and alkaline phosphatase (197.06 U/L).
However, HEV infection must be examined as a possibility if unexplained increases in ALT should occur and after more common viral hepatitis infections are excluded.
We screened 735 HIV-infected patients in Switzerland with unexplained alanine aminotransferase elevation for hepatitis E virus (HEV) immunoglobulin G. Although HEV seroprevalence in this population is low (2.6%), HEV RNA can persist in patients with low CD4 cell counts.
To investigate whether de novo subclinical infection of hepatitis E virus (HEV) has recently increased in Japan, HEV RNA was assayed in serum samples obtained from 4019 Japanese voluntary blood donors with alanine aminotransferase (ALT) of > or =61 IU/l, who are likely to have ongoing HEV infection, during 1991-2006.
At least 25 patients (78%) had consumed uncooked or undercooked pig liver and/or intestine 1-2 months before the onset of hepatitis E. When compared with the seven patients with HEV genotype 3, the 25 patients with HEV genotype 4 had a higher peak alanine aminotransferase (ALT) level (P=0.0338) and a lower level of lowest prothrombin activity (P=0.0340).
The present study indicates that even an individual with subclinical HEV infection had evidence of transient viremia in the absence of ALT elevation and that anti-HEV IgA detection may be useful for serological diagnosis of recent subclinical HEV infection.
This study suggests that a small but significant proportion of blood donors in Japan with or without elevated ALT are viremic and are potentially able to cause transfusion-associated hepatitis E.