[Effectiveness of the use of nutrient media in isolation of Yersinia]. / Effektivnost' primeneniia pitatel'nykh sred dlia vydeleniia iersinii.

Three liquid nutrient media (phosphate buffer medium, 1% buffered peptone water pH 7.6-7.7, buffer casein yeast medium) and live solid media (Endo's, Serov's, and differential diagnostic medium with bromothymol blue, made in this country, and two foreign ones, agar deoxycholate and McConkie's) are compared in examinations of the material from 213 patients with acute intestinal diseases and from 460 small mammals. The results demonstrate a higher efficacy of bacteriologic investigations carried out in the new buffer casein yeast medium or 1% buffered peptone water, pH 7.6-7.8. The data are also indicative of the essential advantages of the differential diagnostic medium with bromothymol blue and prompt its wide practical use.

[Detection of virulence markers in clinical strains of Yersinia]. / Vyiavlenie markerov virulentnosti u klinicheskikh shtammov iersinii.

The dispersion of plasmid pYV associated virulence markers in 474 Yersinia strains isolated from people has been studied. The ability to autoagglutination, calcium dependence of growth and the specific antigens were identified in 157 strains of traditionally pathogenic Yersinia enterocolitica serovars 03, 09, Yersinia pseudotuberculosis serovar I. They were not found in 223 strains of other 12 serovars of Yersinia enterocolitica, in 40 strains of Yersinia frederiksenii, Yersinia kristensenii, Yersinia intermedia. The proportion of virulent clones in the population of Yersinia is noted to depend on the conditions of its existence in vivo or in vitro. Identification of virulence markers is acknowledged to be expedient in epidemiological and ethiological estimation of the role of isolated Yersinia strains.

[The prevalence of Yersinia and its serologic variants in patients with acute intestinal diseases of undetermined etiology in Leningrad]. / Rasprostranennost' iersinii i ikh serologicheskie varianty u bol'nykh ostrymi kishechnymi zabolevaniiami neustanovlennoi étiologii v Leningrade.

Among Yersinia enterocolitica strains of 32 serovars, proposed as typing strains, some strains were found to belong to new species. Y. enterocolitica sensu stricto was represented by 21 serovars in the collection of typing strains. The occurrence of different Yersinia serovars in patients with acute enteric diseases of unknown etiology in Leningrad in 1983-1986 was determined with the use of the set of monoreceptor to 21 serovars. Out of 2,947 cultures studied by biochemical and serological methods, 81% were typed. Among them 18 Y. enterocolitica serovars were determined. Their characteristic feature was the prevalence of serovar O3 and an insignificant proportion of serovar O9. More frequently Yersinia were detected in patients with the primary diagnosis of acute enteric diseases (93.5%). The overwhelming majority (two-thirds) of Yersinia strains were isolated from children. A great number of strains detected in this study (70%) was isolated on days 10-15 of the bacteriological examination. In 927 cultures the following biovars were determined: the strains of serovar O3 belonged to biovar 4 and all other strains, to biovar 1.

[Serological variants of Yersinia enterocolitica circulating in different geographical areas of the Soviet Union]. / Serologicheskie varianty Yersinia enterocolitica, tsirkuliruiushchie v razlichnykh geograficheskikh zonakh Sovvetskogo Soiuza.

The serological variants of a number of Y. enterocolitica strains isolated in different regions of the USSR (1,085 strains isolated from humans and animals in the North-West of the RSFSR, 76 strains isolated from humans and animals in the Krasnodar Territory and 114 strains isolated from humans only in the area east of Lake Baikal) were determined. 25 serological variants were registered in these 3 regions of the USSR. The cultures isolated from rodents belonged mostly to serovars 06,30; 03; 05; 04,33; 019,8; 016; and from humans, to serovars 03; 05; 07,8; 016; 06,30; 09.