[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.

[Eltor cholera in Latin America]. / Kholera El'tor v Latinskoi Amerike.

Cholera epidemics in South and Central America in the period 1991-1999 are characterized. The mechanisms of existence of Vibrio eltor in environmental objects have been substantiated. The causes and conditions of endemic foci formation which determine the infection spread not only within the countries of the subcontinent, but also far beyond its borders are shown. The effectiveness of cholera control interventions is evaluated.

[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 interrelationships between Vibrio cholerae and the infusorian Tetrahymena pyriformis]. / Izuchenie vzaimootnoshenii Vibrio cholerae s infuzoriiami Tetrahymena pyriformis.

The results of the study of interaction between V. cholerae of different virulence and T. pyriformis are presented. The study has revealed the heterogeneity of V. cholerae population: alongside easily phagocytized vibrios, there are vibrios resistant to the digestive action of T. pyriformis. An increase in the number of V. cholerae in association with T. pyriformis has been evaluated, taking into account the selective multiplication of vibrios resistant to phagocytosis. The data on changes in the agglutinative, phagolytic and virulent properties of V. cholerae cultivated together with T. pyriformis are presented. The suggestion has been made that protozoa can function as hosts of pathogenic vibrios supporting their existence in water.