[Hepatitis E in a nonendemic region: antibodies to hepatitis E virus in various groups of residents]. / Gepatit E v neéndemichnom raine: antitela k virusu gepatita E v razlichnykh gruppakh naseleniia.

Increase in the number of seropositive subjects in the population of European and North-American regions not endemic for hepatitis E stimulated research in this field. This study was aimed at investigating the incidence of IgG antibodies to hepatitis E virus (anti-HEV-IgG) in subjects with different liver diseases and in groups at increased risk of infection in a nonendemic region. In patients with different diseases of the liver the incidence of anti-HEV-IgG varied from 5.1 to 14.3%, in medical workers and former blood donors not allowed to donate blood because of increased transaminase levels in the blood 5.1 and 5.3%, respectively. In the reference group this level was appreciably lower-only 1.8%, this being rather close to the incidence of anti-HEV-IgG in the population of a nonendemic region (2.1%). There were no seropositive women in the group of healthy pregnant women in a non-endemic region, whereas in an endemic region (in Kyrghyzstan) 15% of pregnant women were seropositive for anti-HEV.

[Further study of experimental hepatitis E in piglets]. / Dal'neishee izuchenie éksperimental'nogo gepatita E u porosiat.

Experimental infection of piglets with a fecal pool containing hepatitis E virus (HEV) strains Osh-25 and Osh-228 confirmed previous results obtained with HEV strain Osh-205 on susceptibility of these animals to hepatitis E. A biphasic increase of transaminase activities, histopathologic changes in the liver, virus excretion with feces were observed in the animals. The genome of viral particles in piglet feces conformed, at least partially, to human HEV RNA. Ultrastructural abnormalities of piglet hepatocytes resembled those in primates with experimental hepatitis E. The number of positive results (during follow-up of the particles and HEV RNA in various organs of experimental animals) was the highest on day 10 after infection. Both the particles and HEV RNA were present in the lymphoid tissue over the entire follow-up period, from day 5 to day 15 postinfection.

Serological survey on hepatitis E virus infection in an endemic area: diagnosis potential of enzyme immunoassay for detection of IgG antibody.

BACKGROUND: Hepatitis E is a major cause of acute icteric disease widespread in tropical and sub-tropical regions but rarely occurring in industrialized countries. Recently solid-phase enzyme immunoassays with recombinant antigens have been introduced for diagnosis of this infection. OBJECTIVES: The aim of this study was to evaluate the diagnostic potential of a newly developed Abbott test for the detection of IgG class antibodies to hepatitis E virus (anti-HEV IgG) in hepatitis patients and 'normal' individuals. STUDY DESIGN: Sera taken from hepatitis patients and individuals without liver disorders in endemic (Kirghizstan and Uzkbekistan) versus non-endemic (Moscow) areas were investigated. In parallel IgG class antibodies to hepatitis A virus (anti-HAV IgG) were determined by an enzyme immunoassay with native HAV antigen. RESULTS: In five groups comprising altogether 86 suspected hepatitis E patients from endemic area the rate of anti-HEV IgG seropositivity varied from 85% to 17%. In Moscow anti-HEV IgG was found in one patient (who also had acute hepatitis B) out of 19. Anti-HEV IgG persisted in an experimentally infected volunteer for at least 12 years after the acute disease. Among the individuals without liver disorders eight out of 173 (4.6%) showed anti-HEV IgG seropositivity in Kirghizstan while there was only one seropositive out of 165 (0.6%) in Moscow. In contrast, anti-HAV IgG were frequently present in the residents of both areas: in Kirghizstan over 90% of individuals from young age groups already had these antibodies; in Moscow the rate of anti-HAV IgG seropositivity constantly increased from 31% in the youngest age group to almost 85% in the oldest one. CONCLUSION: Prevalence of anti-HEV antibodies was unexpectedly low in endemic area; in Moscow anti-HEV IgG was found only in single cases. Anti-HEV IgG seropositivity in a single serum sample could be of certain diagnostic value in non-endemic areas.

[An experimental infection in lambs by the hepatitis E virus]. / Eksperimental'naia infektsiia iagniat virusom gepatita E.

Lambs were experimentally infected with a pool of 10% hepatitis E (HE) patient fecal suspension containing HE virus (HEV) isolates Osh-225 and Osh-228 which caused an infection closely resembling experimental HE in primates. Clinical manifestations consisted of acute biochemical and histological hepatitis, virus shedding in feces, the presence of virus-like particles in the peripharyngeal lymph nodes and the contents of small intestine, of HEV RNA in the parenchymal organs of lambs. Susceptibility of lambs to HEV derived from the infected piglets and the possibility of passaging the piglets' HEV in lambs was demonstrated. This passaging led to shortening of the incubation period.

[The possible involvement of rodents in the spread of viral hepatitis E]. / Vozmozhnoe vovlechenie gryzunov v rasprostranenie virusnogo gepatita E.

The outbreak of hepatitis E among humans in July-October 1989 in the village of Dzhigdele (140 km to the northeast of Osh) is described. During this outbreak 23 rodents of different species (4 Turkestan rats, 15 house mice and 4 wood mice) were caught within a radial distance of 1 km from the village. 5 out of these 23 animals were found to have hepatitis E virus, detected by the method of immuno-electron microscopy, in their blood sera. Under experimental conditions 7 noninbred white mice were inoculated with material obtained from a previously infected Javanese macaque and a hepatitis E patient. The use of immunoelectron microscopy made it possible to reveal the excretion of the virus with feces on days 4 to 19-23 after inoculation and the development of specific seroconversion in all 7 infected animals. On the basis of these data a suggestion was made that rodents probably played a certain role in the process of the spread of viral hepatitis E.

[Experimental hepatitis E infection in piglets]. / Eksperimental'naia infektsiia gepatita E u porosiat.

A sample of patient's faeces containing virus-like particles (VLP) of 27-34 nm was obtained during an outbreak of hepatitis E in the Kirghiz SSR. The identity of the VLP to hepatitis E virus and etiological association with the disease were demonstrated by immune electron microscopy and infection of Macaca fascicularis monkeys. This isolate of hepatitis E virus is able to induce experimental infection in domestic piglets which was very similar to experimental hepatitis E in primates when infected orally, intravenously and by the combined routes. The clinical manifestations included acute biochemical and histological hepatitis, excretion of hepatitis E virus in faeces, icteric sclerae and skin, hepatitis virus presence in the material from mesenteric lymph nodes. Immunosuppression aggravated hepatitis E infection in piglets. Piglet-to-piglet transmission of hepatitis E virus was demonstrated. During passages of the virus in piglets a shortening of the incubation period and the absence of jaundice was observed.

[Morphological data on the reproductive characteristics of the LEIV-108A and LEIV-3306 Uz strains of the Baku virus in chick fibroblast cell culture]. / Morfologicheskie dannye o nekotorykh osobennostiakh razmnozheniia shatmmov LEIV-108A i LEIV-3306 Uz virusa Baku v kul'ture kletok kurinykh fibroblastov.

Electron microscopic examinations of chick fibroblast cells 24 hours after inoculation with LEIV-108A and LEIV-3306 Uz strains of Baku virus revealed the following: in the nuclei of the cells infected with the LEIV-108A strain fine granular matrices were found and virus particles were forming at the periphery of the nucleus; in the LEIV-3306Uz-infected cells virus particles were found budding from the plasma membrane of the cell.

[Study of the morphological aspects of Okhotskii virus replication in a chick fibroblast culture]. / Izuchenie morfologicheskikh aspektov replikatsii virusa Okhotskii v kul'ture kurinykh fibroblastov.

Electron microscopic studies of chick embryo fibroblast cells 24 hours after infection with Okhotsky virus revealed changes typical orbivirus infection in the cytoplasm and the nuclei of the cells. The nuclei of the infected cells contained fine-granular matrices with forming virus particles and tubular structures. The cell cytoplasm also contained tubular structures, crystal arrays, fine-granular matrices and virus particles 50-60 nm in diameter.