Whole-Genome Sequencing of a Vibrio cholerae El Tor Strain Isolated in the Imported Cholera Focus in Siberia.

The draft genome sequence of Vibrio cholerae O1 strain I-1263, isolated from a patient in the imported focus in Siberia, was determined. The established structural features of the mobile genetic elements indicate stage-by-stage formation of a highly pathogenic V. cholerae clone and promote understanding of the mechanisms of evolutionary pathogen transformations.

[Cholera and war].

During last centures wars were the main account of spread of cholera. It is caused by movement of great mass of troops and peaceful populace, acute fall of living circumstances, decline of sanitarium conditions of population aggregates, difficultness or impossibility of effectuating of contra-epidemic measures. Cholera casualty was multifold bigger, the weapon casualty in fighting armies. The article presents data of cholera epidemics, were in fighting armies of different states. During the XXth century fight casualty began to overpass the disease casualty. It is caused by grand increasing of damage effects of measures of war, organized using of prophylaxis measures and success in treatment of infectious diseases. The article presents data about cholera falling ill during the Great Patriotic War and about system of contro-epidemic barrier on fronts and rear of state.

[PCR-detection of markers for epidemiologically-significant strains of Vibrio cholerae 0139, isolated in Siberia]. / PtsR-detektsiia markerov épidemicheskoi znachimosti shtammov Vibrio cholerae 0139, izolirovannykh v Sibiri.

Fourteen V. cholerae 0139 strains were isolated in 1996-1999 in Siberia from the Ob river (Novosibirsk) and bogs and lakes (Irkutsk). The strains were tested in PCR for the key virulence determinants (ctx AB, tcp, acf). The genomes lacked these elements, and therefore the strains were acknowledged avirulent. The results correlate completely with the data of phenotypical analysis, characterizing the pathogenic characteristics of isolated strains.

[Cholera in the Far East of Russia. Communication 2. Epidemiological characteristics of the outbreak of cholera El tor in Iuzhno-Sakhalinsk]. / Kholera na Dal'nem Vostoke Rossii. Soopshchenie 2. Epidemiologicheskaia kharakteristika vspyshki kholery él'tor v g. Iuzhno-Sakhalinske.

The outbreak of cholera eltor in Yuzhno-Sakhalinsk has been analyzed. The fact of the import of this infection from China and its transmission mainly by the water route due to the intensive contamination of environmental objects has been substantiated. The effective purification decontamination of sewage water plays decisive role on the system of anticholera measures. The conclusion on the necessity of increasing the effectiveness of measures for the sanitary protection of the territory has been made.

[Comparative study of various methods for determining Vibrio cholerae toxigenicity]. / Sravnitel'noe izuchenie razlichnykh metodov opredeleniia toksigennosti Vibrio cholerae.

Testing of 138 Vibrio cholerae strains for gene determinants responsible for the production of cholera enterotoxin by the polymerase chain reaction (PCR) and gene probing using molecular CT-probe showed good correlation of the results of different methods and correlation of these data with studies of V. cholerae strain virulence in vivo and in hemolytic activity test. The advantages of PCR in rapid assessment of the toxigenicity and epidemic significance of V. cholerae strains are demonstrated.

[The characteristics of the protectiveness of a preparation of Vibrio cholerae outer membrane based on the data from a study using the ligated intestinal loop]. / Kharakteristika protektivnosti preparata naruzhnoi membrany kholernogo vibriona po dannym issledovaniia pereviazannoi kishechnoi petli.

The study aimed at finding out the antiadhesive capacity of antigenic preparation, earlier obtained from V. cholerae outer membrane and highly effective with respect to cholera infection, was undertaken. The study was made on previously immunized adult rabbits who had been subjected to laparotomy under anesthesia and the ligation of intestinal loops, subsequently inoculated with the broth culture of V. cholerae eltor (P-3122, serovar Ogawa). The intestinal loops were studied histologically and bacteriologically with the calculation of the number of vibrios, the deduction of the adhesion index and the coefficient of the efficacy of immunization. The data thus obtained indicated that the specific immunization of rabbits with their subsequent inoculation with V. cholerae virulent strain suppressed the adhesive activity of the infective agent which was more pronounced in rabbits immunized with the preparation of V. cholerae outer membrane.

[The characteristic properties of Vibrio cholerae eltor isolated from environmental objects on the territory of the former USSR during the 7th cholera pandemic]. / Kharakteristika nekotorykh svoistv Vibrio cholerae eltor, vydelennykh iz ob''ektov okruzhaiushchei sredy na territorii byvshego SSSR vo vremia sed'moi pandemii kholery.

The properties of 22,382 V. eltor strains isolated from environmental objects on the territory of different climatic and geographical zones during the period of 1970-1988 were studied. The study was made on the morphology of their colonies, the agglutinability of the strains by cholera O serum, type-specific serum and RO serum, their capacity for being lyzed by V. eltor bacteriophage, their hemolytic activity and virulence. Differences in the occurrence of strains with any of the above-mentioned properties, depending on the object from which they were isolate, the climatic and geographical zone and the intensity of the epidemiological situation with regard to cholera.

[Dynamics of drug resistance of Vibrio cholerae isolated from surface water reservoirs in Siberia and the Soviet Far East in 1976-1990]. / Dinamika lekarstvennoi ustoichivosti kholernykh vibrionov, vydelennykh iz poverkhnostnykh vodoemov Sibiri i Dal'nego Vostoka v 1976-1990.

In the study on antibiotic resistance 1383 strains of El Tor Vibrio cholerae isolated from surface water reservoirs in 12 administrative territories of the Siberia and Far East within a period of 15 years were tested. The following antibiotics were used: ampicillin, streptomycin, monomycin, polymyxin, tetracycline, chloramphenicol, rifampicin and nalidixic acid. The resistance was unstable and its pattern was wave-like according to annual changes in the biological cycle. It was especially evident in regard to ampicillin, streptomycin, monomycin and polymyxin. The highest numbers of the strains were resistant to polymyxin, ampicillin and streptomycin (up to 100 per cent in some years). The lowest numbers of the strains were resistant to chloramphenicol (0.4 per cent) and tetracycline (1.9 per cent). No strains resistant to rifampicin and nalidixic acid were isolated. In some cases the antibiotic resistance level depended on the geographical zone where the strain was isolated. A direct quantitative dependence of the resistance level on the MIC was observed: the lower the MIC of the drug was, the lower the number of the strains resistant to it was. Within the 15-year period there was no general tendency to increase the resistance in V. cholerae to the antibiotics used.

[Comparative antibiotic sensitivity of NAG vibrios]. / Sravnitel'naia chuvstvitel'nost' k antibiotikam NAG-vibrionov.

Six hundred and forty eight NAG vibrio strains isolated at various periods from patients and carriers and from environmental objects such as surface of water reservoirs and sewage were studied with respect to their sensitivity to 14 antibiotics with the method of serial dilutions in solid media. Irrespective of the isolation place, object and time, the NAG vibrios were highly resistant to penicillins and polymyxin M. At the same time they were highly sensitive to gentamicin (MIC 1-2 micrograms/ml), levomycetin (MIC 0.5-1 micrograms/ml) and tetracyclines (MIC 0.25-1 micrograms/ml). Study of the recipient capacity of NAG vibrios with respect to R plasmids showed that they could be recipients of exogenic R plasmids of various incompatibility groups.

[Phage typing of nonagglutinating vibrios isolated in the territory of the USSR]. / Fagotipirovanie neaggliutiniruiushchikhsia vibrionov, vydelennykh na territorii SSSR.

The work presents the results of the phage typing of 2,437 NAG vibrio strains isolated in the USSR from patients and carriers (374 strains), from open water basins (1,675 strains), from sewage (234 strains) and from bottom silt (172 strains). Phage typing was carried out with a set of 5 phages capable of lyzing enteropathogenic NAG vibrios (phages TEPV 1, 2, 3, 4, 5). NAG vibrios isolated from humans were sensitive to phages TEPV in 45% of cases and NAG vibrios isolated from the environment, only in 29.9% of cases. Enteropathogenic NAG vibrios belonging to phagovar 1 were isolated most frequently from samples taken both from humans and from the environment. The NAG vibrios isolated from patients, carriers and the sources of water supply nearest to them belonged to the same phagovars.

[Serological typing of Vibrios, nonagglutinating with O-cholera serum, isolated in USSR]. / Serologicheskoe tipirovanie ne aggliutiniruiuschikhsia O-kholernoi syvorotkoi vibriunov, vedelennykh na territorii SSSR.

The authors carried out serological typing of 2008 strains of NAG vibrios isolated in 1968--1975 in 18 territories of the Soviet Union from humans and from the objects of environment. Serological type was established in 40.5% of the srains isolated from humans and in 16% of the strains obtained from the environmental objects. Among persons with acute gastrointestinal diseases serotype 5 was the one which dominated, and among strains from the environment--serotype 8 Sakazaki. Serological type 15 was revealed for the first time in the USSR at the territory of Siberia and the Far East among the NAG-vibrio strains isolated from the environment.