[The factors that affect the results of the serological diagnosis of HIV infection and the screening for anti-HIV]. / Faktory, vliiaiushchie na rezul'taty serologicheskoi diagnostiki VICh-infektsii i skrining na anti-VICh.

The laboratory diagnosis of HIV infection and screening for anti-HIV have determined the factors that influence the results of studies performed by ELISA and Western immunoblot. The factors include sensitivity and specificity of the test systems used, storage conditions of and transportation conditions for serum, errors of procedures for reactions, etc. Correlation is between the inactivation of the sera studied and the initial antibody titers during their storage at elevated temperatures. To obtain more valid results of HIV infection serodiagnosis it is necessary to use some test systems differing in the principles of setting up a reaction.

Biological properties of strains of tick-borne encephalitis virus isolated in the natural foci of the eastern part of the Russian plain.

Strains of tick-borne encephalitis virus isolated in the natural foci of infection in the eastern part of the Russian Plain (the Kirov region) were examined for their biological properties. The strains examined were 69 strains isolated from ticks Ixodes persulcatus, 62 strains obtained from patients with the clinically manifest form of tick-borne encephalitis and 56 strains isolated from the blood of patients with the inapparent form of infection. Comparative studies on laboratory animals (albino mice, golden hamsters, suckling guinea pigs and other mammals) as well as comparative serologic studies provided evidence which suggested that all virus isolates from the Kirov region were antigenically identical with the strain "Sofin" isolated in the Far East and represent thus a single causative agent of the tick-borne encephalitis virus infection. This strain of virus is supposed to exist in two variants, in dependence on ecological conditions: one of these variants is the eastern variant (strain Sofin and strains from the Kirov region) and the other one is the western variant of tick-borne encephalitis virus.

[Detection of antibodies to the causative agents of viral infections in multiple sclerosis patients]. / Obnaruzhenie antitel k vozbuditeliam nekotorykh virusnykh infektsii u bol'nykh rasseiannym sklerozom.

Serological examinations of blood sera from patients with multiple sclerosis (MS), their nearest relatives, and subjects of the control groups for antibodies to causative agents of some viral infections demonstrated antihemagglutinins to measles and rubella viruses in 61%-95.5% of the subjects examined in all the groups, to mumps virus in 53% in MS patients, to tick-borne encephalitis virus in 2.2% in the same group, and in 10.5% in the group of patients with other CNS diseases, and none in healthy subjects. Virus-neutralizing antibodies to human acute encephalomyelitis virus (HAEM) in 28% of the cases, frequently in the stage of remission. Specific IgM to measles virus was found in 41% of MS patients, in 15% of their nearest relatives, and in 19.7% of patients with other CNS diseases, but not in healthy subjects. No differences in the rate of antibody findings to herpes simplex virus types 1 and 2 were observed in the groups examined. The rate of detection of virus-neutralizing antibody to HAEM virus was significantly higher in MS patients with the severity of the course of IV-V degree (20%) than of the II-III degree (8.8%). In the period of MS exacerbation the level of specific IgM to measles virus increased (35.6%), and higher titres of antihemagglutinins were observed in patients with longer duration of the disease and higher degree of its severity.

Immunological activity against tick-borne encephalitis virus in fractions of sera from goats of different ages.

A comparative analysis of the antihaemagglutinating, virus-neutralizing and complement-fixing activities of 19 S, 7 S, 4S and 1.5 S fractions of blood sera from goats of different ages pastured in a tick-borne encephalitis focus was carried out. Changes in the immunological activity of different fractions in relation to the age of the animals are discussed.