[Prognosis of the dynamics and intensity of the epidemic process in viral hepatitis A]. / Prognozirovanie dinamiki i intensivnosti épidemicheskogo protsessa pri virusnom gepatite A.

The article deals with approaches to the calculation of the annual morbidity rate in virus hepatitis A at the period preceding the season of maximum morbidity, necessary for planning the relevant prophylactic and antiepidemic measures in due time. The method for calculating the monthly levels of sporadic morbidity in virus hepatitis A is proposed. This method permits the detection of complications on the epidemic situation, which is necessary for the timely organization of antiepidemic measures. The proposed method for predicting annual and monthly morbidity levels can be used in the practical work of specialists at sanitary and epidemic stations.

[Comparative evaluation of several methods of diagnosing hepatitis A]. / Sravnitel'naia otsenka nekotorykh serologicheskikh metodov diagnostiki virusnogo gepatita A.

Immunofluorescence (IF), indirect hemagglutination test (IHA), latex-agglutination test (LA), and immunofluorescence of activated sepharose particles (IFS) were used for early specific diagnosis of viral hepatitis A (VHA). The antisera used in the tests were those from convalescents after VHA collected at 25-30 days which had no HBs antigen or antibody to it. The IF and IHA tests were found to be most sensitive for examination of VHA patients. In VHA foci, positive IF tests were found in 22%-72% contacts (in relation to the number of manifest forms in a focus of infection) which in 84.6% cases correlated with enlarged liver. In parallel examination of contacts in one of VHA foci by IF and IHA tests similar results were obtained and the infection-rate in the group was 64.3% and 64% respectively.

[Further study of the leukocyte virus isolated in hepatitis A]. / Dal'neishee izuchenie leikotsitarnogo virusa, vydelennogo pri gepatite A.

Two strains of leukocyte hepatitis virus (LHV) which had undergone 13 and 16 passages, respectively, in phytohemagglutinin-stimulated cultures of leukocytes from normal donors were studied in experiments with labelled precursors (3H-uridine and 14C-amino acids). The buoyant density of the virus (1,26 g/ml) and sedimentation constant of RNA (46 S) were determined. LHV was shown to be capable of reproduction in human kidney cell culture. The immunofluorescence test could be used with labeled convalescent sera for examinations of blood smears from patients for diagnosis of hepatitis A in foci of infection. In these tests, fluorescence was detected in the cytoplasm of lymphocytes and granulocytes but not in the nucleus. The immunofluorescence test with convalescent sera was successfully used for the examinations of smears of cultures of PHA-stimulated leukocytes of normal donors infected with LHV in order to prove the specificity of this virus in hepatitis A.

[Possibilities of viral hepatitis diagnosis by immunofluorescent examination of patient blood smears]. / O vozmozhnosti diagnostiki virusnogo gepatita pri obsledovanii mazkov krovi bol'nykh s pomoshch'iu metoda immunofliuorestsentsii.

The authors demonstrate possibilities of viral hepatitis diagnosis by means of fluorescent antisera labeled phiiTts. The antisera were obtained from the blood of convalescents after infectious hepatitis (with an uncomplicated course) on the 25th--30th day of the disease, and also from the placental gamma-globulin of persons who had had viral hepatitis (in the anamnesis). Both diagnostic preparations proved to be highly specific, although the first of them was somewhat more sensitive. Blood smears were stained with fluorescent antisera. The fluoresence was revealed in the cytoplasm of the white blood formed elements--lymphocytes and neutrophils; the nucleus was dark. Materials of this investigation permit experimental substantiation of a possibility of prolonged antigenemia in the blood leukocytes of patients suffering from viral hepatitis.