In a high-risk population, the rHEV vaccine was effective in the prevention of hepatitis E. (ClinicalTrials.gov number, NCT00287469 [ClinicalTrials.gov].).

Viremia, fecal shedding and antibody responses to hepatitis E virus (HEV) infections are poorly understood. To better characterize HEV infections, these responses were examined in 67 patients with acute markers for hepatitis E who were admitted to the Infectious Disease Hospital in Kathmandu, Nepal in 1993. A single stool and multiple sera from each patient were examined using polymerase chain reaction to detect HEV RNA. Sera were also examined for antibodies to HEV. Viremia, fecal shedding, and IgM and IgG to HEV were detected in 93%, 70%, 79%, and 87% of 67 patients, respectively. Viremia or fecal shedding (or both) were detected in 14 patients from whom IgM and IgG to HEV were not detected. Viremia lasted at least 2 weeks in nearly all subjects and at least 39 days in 1 subject. Our results suggest that viremia is a common occurrence in patients infected with HEV.

No abstract

and Bruce L. InnisTo determine hepatitis E virus (HEV) infection and disease rates in the Kathmandu Valley of Nepal, serum was collected from 757 healthy Nepalese (ages 12 -48 years) during March and September 1992 and September 1993. At each visit, reports of interval illness were obtained. Sera were examined for IgG to HEV, using a commercially available kit. Seroconversion was used as a marker for HEV infection, and an episode of hepatitis E was defined as a history of jaundice with seroconversion. Seroprevalence ranged from 16% to 31% and increased with age, whereas both infection and disease rates decreased with age. Infection and disease rates were as high as 99/1000 and 45/1000 person-years, respectively. These results highlight the importance of sporadic hepatitis E as a public health problem among adolescents and young adults in this region. Hepatitis E virus (HEV) is believed to be the primary agentStudies to characterize the prevalence of IgG to HEV began as a result of the recent development of serologic assays for responsible for enterically transmitted non-A, non-B hepatitis. The most commonly reported signs and symptoms of this dis-HEV. Generally, the prevalence of antibody against HEV is low (0% -3%) in areas where no outbreaks have been reported ease include malaise, jaundice, dark urine, nausea, abdominal pain, fever, hepatomegaly, and vomiting [1]. The mortality rate and sporadic cases are rare (e.g., in the United States, Europe, Australia, Japan, New Zealand, South Africa, and Thailand) for hepatitis E is higher than for hepatitis A and ranges from 1% -3% among men and nonpregnant women to 12% -42% [5 -8]. By contrast, the prevalence of antibody against HEV is higher (10% -40%) in regions where outbreaks have been among pregnant women [2]. High rates of perinatal death are also associated with this disease [3,4]. Hepatitis E is an imreported and sporadic transmission occurs regularly, such as India, Nepal, and Tajikistan [6,7,9, 10]. Age-specific antibody portant health concern in nearly all under-developed regions of the world. No vaccines for hepatitis E have been developed, prevalence has been examined in India and Nepal [9, 10]. In both studies, antibody prevalence was found to increase with and prophylaxis with immune serum globulin appears to have little or no protective effect [2]. age until about age 30 years. No increase in antibody prevalence was apparent after age 30. No sex-dependent differences in antibody prevalence were observed; on the other hand, in older age groups, the numbers of women were too small to NOTE. Serum and medical histories were collected from 757 persons during March and September 1992 and September 1993. Case of hepatitis E was defined as episode of jaundice (self-reported during interview) along with acquisition of IgG to HEV during period examined. Infection was based on acquisition of HEV antibody during period examined. IgG to HEV was detected using ELISA developed by Diagnostic Biotechnology (Singapore). All 3 serum specimens from each individual were ...

Diagnosis of acute hepatitis E by detection of hepatitis E virus (HEV)-specific immunoglobulin M (IgM) isan established procedure. We investigated whether quantitation of HEV IgM and its ratio to HEV total Ig furnished more information than conventional IgM tests that are interpreted as positive or negative. A previously described indirect immunoassay for total Ig against a baculovirus-expressed HEV capsid protein was modified to quantitate HEV-specific IgM in Walter Reed (WR) antibody units by using a reference antiserum and the four-parameter logistic model. A receiver-operating characteristics curve derived from 197 true-positive specimens and 449 true-negative specimens identified 30 WR units/ml as an optimum cut point. The median HEV IgM level in 36 patients with acute hepatitis E fell from 3,000 to 100 WR units/ml over 6 months, suggesting that 100 WR units/ml would be a more appropriate cut point for distinguishing recent from remote IgM responses. Among three hepatitis E case series, determination of the HEV IgM-to-total-Ig ratio in acute-phase serum revealed that most patients had high ratios consistent with primary infections whereas a few had low ratios, suggesting that they had sustained reinfections that elicited anamnestic antibody responses. The diagnostic utility of the new IgM test was similar to that of a commercially available test that uses different HEV antigens. In conclusion, we found that HEV IgM can be detected specifically in >95% of acute hepatitis E cases defined by detection of the virus genome in serum and that quantitation of HEV IgM and its ratio to total Ig provides insight into infection timing and prior immunity.Hepatitis E is acute, self-limited hepatitis caused by a virus of the same name (hepatitis E virus [HEV]) that is excreted in feces and transmitted orally. In large parts of Asia and Africa, this disease is common, causing sporadic and epidemic illness (10). Diagnosis of acute hepatitis E is based on detection of the HEV genome in serum or feces by reverse transcription-PCR (RT-PCR) (1, 2, 13) or detection of newly elicited antibodies to HEV, in particular HEV-specific immunoglobulin M (IgM) (2,11,12,16,17). An IgM test is marketed in Asia (18); this test uses recombinant HEV antigens derived from the carboxyl terminus of the capsid protein (ORF-2) and ORF-3. The good diagnostic utility of the marketed test has been characterized (2, 6). Moreover, several research laboratories have developed IgM tests based on alternative recombinant HEV (rHEV) antigens expressed in bacteria (11) or by use of the baculovirus system (12, 16).Recently, we reported an indirect enzyme immunoassay (EIA) for total Ig against a baculovirus-expressed HEV capsid protein that quantitated antibodies to HEV in Walter Reed (WR) antibody units by using a reference antiserum and the four-parameter logistic model (9). We modified this test to detect HEV-specific IgM and employed the IgM and total-Ig tests together to characterize serum specimens from patients with suspected acute hepatitis E. We invest...