Characterization of the Shiga toxin-producing Escherichia coli O26 isolated from human in Poland between 1996 and 2014.

Shiga toxin-producing Escherichia coli (STEC) O26 infections can be comparable with STEC O157 infections in severity of the acute haemolytic-uremic syndrome HUS and long-term sequelae. Among O26 STEC isolates, highly virulent clone O26:H11/H- Sequence Type 29 (ST 29) emerged in Germany in mid-1990s and spread to European countries. However, up to date, no STEC O26:H11/H- belonging to ST29 has been documented in Poland. In this study, we determined the relationship and clonal structure, stx genotypes, plasmid gene profiles and antimicrobial resistance of nine human STEC O26:H11/H- strains from human patients in Poland between 1996 and 2014. Of the 9 human STEC O26:H11/H- strains, two belonged to ST29 and were isolated from two children with HUS and renal failure with sepsis respectively. These strains showed the molecular characteristics of the emerging human-pathogenic ST29 clone (stx1-, stx2a+, eae+, ehxA+, etpD+, katP-, espP-). The remaining STEC O26:H11/H- strains examined in this study, belonged to ST21, with plasmid genes profiles frequently reported in ST21 strains in Europe. STEC O26 infections with serious human health consequences highlight the need of continuous surveillance of non-O157 STEC and implementation of the diagnostic approaches focused on their detection. Significance and impact of the study: These study provides the first data on the occurrence of emerging Shiga toxin-producing Escherichia coli O26:H11 ST 29 clone in human patients in Poland. Those strains show the molecular characteristics of highly virulent new ST29 pathotype (stx1-, stx2a+, eae+ ehxA+, etpD+, katP-, espP-). These results demonstrated prompt efforts to implement diagnostic approaches detection of those pathogen in the European countries.

Seasonality of Yersinia enterocolitica bioserotype 1B/O:8 infections in Poland.

Both serological and bacteriological investigations revealed a cyclic, seasonal pattern of Yersinia enterocolitica 1B/O8 infections in Poland during the years 2008­2011. A large increase in incidence was observed in the second quarter and a decrease in the third quarter of each year. Such seasonal changes were not seen in the case of infections caused by the other enteropathogenic Yersinia bioserotypes.

Ensuring safety of home-produced eggs to control salmonellosis in Poland: lessons from an outbreak in September 2011.

Implementation of control measures in line with European Commission regulations has led to a decrease in salmonellosis in the European Union since 2004. However, control programmes do not address laying hens whose eggs are produced for personal consumption or local sale. This article reports an investigatxion of a salmonellosis outbreak linked to home-produced eggs following a family event held in a farm in September 2011 near Warsaw, Poland. In the outbreak, 34 people developed gastroenteritis symptoms. Results from a cohort study indicated a cake, prepared from raw home-produced eggs, as the vehicle of the outbreak. Laboratory analysis identified Salmonella enterica serotype Enteritidis (S. Enteritidis) in stool samples or rectal swabs from 18 of 24 people and in two egg samples. As no food items remained, we used phage typing to link the source of the outbreak with the isolated strains. Seven S. Enteritidis strains analysed (five from attendees and two from eggs) were phage type 21c. Our findings resulted in culling of the infected laying hens and symptomatic pigeons housed next to the hens. Salmonella poses as a public health problem in Poland: control measures should not forget home-produced eggs, as there is a risk of infection from their consumption.

The first report on Campylobacter coli family outbreak detected in Poland in 2006.

A family outbreak of gastroenteritis caused by Campylobacter coli occurred in May 2006 in Bielsko-Biala, in the south of Poland. Four members of a family had non-bloody diarrhea and abdominal cramps. C. coli were isolated in three of the four patients. PFGE and PCR-RFLP-flaA patterns confirmed the link between cases, showing the usefulness of these methods in outbreak investigation. At the same time, the epidemiological and environmental investigations of this outbreak were very limited and did not provide enough evidence to identify the source of infection, and thus to support the hypothesis formulated by the local epidemiologist. It is necessary to improve surveillance of campylobacteriosis mainly by multidisciplinary training of epidemiologists, microbiologists and general practitioners.

Antibiotic resistance in Salmonella enterica subsp. enterica strains isolated in Poland from 1998 to 1999.

A total of 326 Salmonella enterica subsp. enterica strains representing 29 serotypes, isolated from human stool specimens during 1998-1999 in sanitary-epidemiological units in Poland were tested for antibiotic susceptibility by a standard disk diffusion method. The antibiotics used were ampicillin, cefotaxime, chloramphenicol, tetracycline, streptomycin, gentamicin, kanamycin, nalidixic acid, ciprofloxacin, furazolidone, cotrimoxazole, sulphonamides and trimethoprim. In addition, 201 strains belonging to the five most commonly isolated serotypes (S. Enteritidis, S. Typhimurium, S. Hadar, S. Infantis and S. Virchow) also had minimal inhibitory concentrations (MICs) determined for amoxycillin/clavulanic acid. Selected strains were screened for production of extended spectrum beta-lactamases (ESBLs). There were 49.4% of Salmonella enterica subsp. enterica strains resistant to two or more antibiotics, with the highest prevalence of multiple resistant strains among serotypes Typhimurium, Hadar and Virchow. Resistance to ampicillin, streptomycin, tetracycline, nalidixic acid, furazolidone and sulphonamides occurred most frequently. Over 93% of S. Virchow strains were resistant to furazolidone. No strains resistant to ciprofloxacin by disk-diffusion method were detected but 31.3% of isolates of the 201 strains representing the five most common serotypes had reduced ciprofloxacin susceptibility (MICs ranging 0.125-0.5 mg/l). One strain (S. Mbandaka) was resistant to cefotaxime and produced ESBL.

[Multidrug resistance to antibacterial drugs of Salmonella enterica subsp. enterica strains isolated in Poland in the 1998-1999 period]. / Wieloopornosc na leki przeciwbakteryjne paleczek Salmonella enterica subsp. enterica izolowanych w Polsce w latach 1998-2000.

A total of 510 Salmonella enterica subsp. enterica strains representing 56 serotypes, isolated from human stool specimens during 1998-2000 in sanitary-epidemiological units in Poland were tested for their susceptibility by a standard disk diffusion method for: ampicillin, cefotaxime, chloramphenicol, tetracycline, streptomycin, gentamicin, kanamycin, nalidixic acid, ciprofloxacin, furazolidone, cotrimoxazole, sulfonamides and trimethoprim. For 201 of the investigated strains, belonging to 5 most common isolated serotypes (S. Enteritidis, S. Typhimurium, S. Hadar, S. Infantis and S. Virchow) the minimal inhibitory concentrations (MICs) for the aforementioned antibiotics, as well as for amoxicillin with clavulanian were determined. Selected strains were screened for production extended spectrum b-lactamases (ESBLs). It was observed that 42.9% of Salmonella enterica subsp. enterica strains were resistant to 2 or more antibiotics, with the highest prevalence of MDR strains among serotypes Typhimurium, Hadar and Virchow. Resistance to ampicillin, streptomycin, tetracycline, nalidixic acid, furazolidone and sulphonamides was observed most frequently. Over 93% of S. Virchow strains were resistant to furazolidone. No strains resistant to ciprofloxacin were detected according to the NCCLS guidelines, but 31.3% of isolates exhibiting reduced ciprofloxacin susceptibility (MICs ranging between 0.125 and 0.5 mg/l). Two strains S. Mbandaka and Salmonella group D (variant motility--) were resistant to cefotaxime and probably produced ESBL.

[Phage types, plasmid profiles and chromosomal restriction profiles of Salmonella enterica subsp. enterica ser. enteritidis (S. enteritidis) isolated in Poland in 1999-2000]. / Typy fagowe oraz profile plazmidowego i chromosomalnego DNA szczepów Salmonella enterica subsp. enterica ser. Enteritidis (S. Enteritidis) izolowanych w Polsce w latach 1999-2000.

Salmonella Enteritidis strains are the most often isolated Salmonella serovars in Poland. In the present study, phage typing, plasmid profile analysis, and PFGE have been applied to characterize 140 Polish S. Enteritidis isolates originated from human cases of salmonellosis and from other sources. The typing phages of Ward and colleagues scheme were used to type a total of 140 S. Enteritidis strains coming from Poland. All 140 strains were typable and six different phage types were observed. A total of 125 (89%) of 140 isolates examined belonged to PT 4. The others PTs were represented by small amount of strains (PT1-2, PT6-6, PT7-1, PT8-4 and PT21-2 strains). Among all tested isolates six different plasmid profiles were observed. Of the 140 examined strains, 128 (91.4%) contained the 57 kb plasmid alone. After XbaI digestion four distinct pulse field chromosomal restriction profiles among studied S. Enteritidis were observed. XbaI and SpeI chromosomal restriction profiles of S. Enteritidis PT4 were identical with reference strain profiles. Our findings confirmed earlier suggestions that the increase of human salmonellosis cases in Poland was caused by S. Enteritidis PT4 and was due to consumption of contaminated food. This study confirmed the importance of using PFGE in combination with phage typing, plasmid typing and antibiotic resistance testing for studying the epidemiology of S. Enteritidis.

[Occurrence of Escherichia coli O157 in feces of healthy persons, from selected groups, in the country]. / Wystepowanie paleczek Escherichia coli O157 w kale zdrowych osób, z wybranych grup, na terenie kraju.

The purpose of the study was determination of the occurrence of E. coli O157 in faeces samples of healthy subjects and characterization of the isolated strains with respect to their potential pathogenicity. The study was carried out in two stages. In the first one in 5 sanitary-epidemiological stations samples were tested from healthy subjects after inoculation onto McConkey (MC) or/and McConkey with sorbitol (SMC) media and isolating from each culture 10 lactose-positive (on MC medium) or sorbitol-negative (on SMC) colonies. Then latex test was done with each isolate for E. coli O157 presence. In all, 1005 samples were studied, including 260 taken from children aged 0-2 years, 180 samples from children aged 3-10 years, and 565 samples from older children and adults. E. coli O157 rods were cultured from 6 adults (0.6%). In the second stage carried out at the Laboratory of Enterobacteriaceae, Bacteriology Department, National Institute of Hygiene strains obtained from territorial laboratories were studied determining their phenotypic and genotypic traits regarded as virulence markers of verotoxic E. coli O157 strains, such as inability to ferment sorbitol and MUG breakdown, and production of verotoxins and enterohaemolysin. By the PCR method fragments were sought of genes coding for production of verotoxins, intimin and enterohaemolysin. The results showed that no E. coli O157 strain obtained from healthy individuals produced verotoxins, but three studied strains contained the eae gene determining intimin production and they were regarded as enteropathogenic.

[The role of rotaviruses in digestive tract infections of hospitalized children with diarrhoea at the Health Care Consortium in Sokol Podlaski]. / Udzial rotawirusów w zakazeniu przewodu pokarmowego dzieci hospitalizowanych z powodu biegunki w Zespole Opieki Zdrowotnej w Sokolowie Podlaskim.

The aim of the study was a trial of establishing of the frequency of rotavirus infection and mixed bacterial-viral infections in children treated for diarrhoea in a hospital in the period from July 1 1996 to June 30 1997. Moreover, an attempt was made at establishing of the frequency of rotavirus colonization of the digestive tract in healthy newborns born in that hospital during the period of that study. The studies were done on feces samples from 169 children with diarrhoea from 4 days to 13 years, and from 30 healthy peers. In all samples rotaviruses were sought along with pathogenic Enterobacteriaceae Tests for rotaviruses were done with Slidex-Rota Kit 2 (Bio-Merieux) and for EPEC with the EPEC latex test (Biomex). In all, rotaviruses were found in 88 ill children (52.1%) including mixed bacterial-viral infections in 10 (5.1%) children. In 9 children beside rotaviruses enteropathogenic E. coli (EPEC) were disclosed, and in 1 child S. enteritidis. Moreover, in 1 child (0.6%) culture yielded simultaneously S. sonnei and E. coli 0127. No rotaviruses were found in any 30 healthy newborns, but from one of them E. coli 018 was cultured. The second most frequent aetiological factor in diarrhoea were EPEC organisms found in 17 (10.0%) children, the third factor were S. enteritidis strains in 6 children (3.6%). In one case S. sonnei and E. coli 0127 were obtained from faces. Rotavirus infection was most frequent in children aged from 2 months to 3 years, and EPEC infection in children up to 2 years. The incidence was highest in winter/spring, with peak in April when 27 cases of rotavirus diarrhoea were noted.

[Characteristics of E.coli O157 strains isolated in Poland from clinical material and food samples]. / Charakterystyka szczepów E. coli O157 izolowanych w Polsce z próbek materialu klinicznego i z zywnosci.

E. coli belonging to the O157 serological group are among the organisms isolated most frequently out of all the so called entero-hemorrhagic E. coli strains (EHEC). Since several years they have been isolated also in Poland. The purpose of the present study was determination on selected phenotypic and genotypic properties of E. coli O157 strains isolated in our country from clinical material samples and from food. The serotype of the strains was determined, together with the following properties regarded as pathogenicity markers of verotoxic E. coli strains such as absence of beta-glucuronidase activity and sorbitol fermentation ability, as well as production of verotoxins SLT I and/or SLT II and entero-hemolysin. Besides that, by the PCR method the fragments of the genes coding for verotoxins, intimin and enterohaemolysin were amplified. The products of PCR were analysed by the restriction enzyme analysis (RFLP). All verotoxic E. coli O157 strains isolated in Poland were analysed by the pulsed field gel electrophoresis of genomic DNA (PFGE). The studied group comprised E. coli O157 strains, among them 40 strains were isolated from human faeces and 5 from food. The remaining strains were the reference E. coli O157:H7 EDL 933 and G 5244 strains and strains from NIH collection. The obtained results showed that the tested strains were a very varying population. 21 of them (all isolated from food, 11 from faeces and 5 reference strains) belonged to serotype O157:H7, five were not peritrichous O157:NM and the remaining ones had other ciliary antigen than H7. All strains isolated from food, reference strains and only 3 O157:NM strains isolated from humans were verotoxic. The strains from food and two reference strains produced only SLT II, 2 of 3 strains isolated from humans and one reference strain also produced only SLT II and the other produced both verotoxins. Apart from these 13 verotoxic strains all remaining strains caused sorbitol fermentation.

[Evaluation of the usefulness of the agglutination test with Mangifera indica extract for the identification of pathogenic Yersinia enterocolitica strains]. / Ocena przydatnosci aglutynacyjnego testu z wyciagiem Mangifera indica do identyfikowania chorobotwórczych szczepów Yersinia enterocolitica.

The study was performed on 137 Y. enterocolitica strains belonging to various serological groups, including 75 03 group strains isolated form human clinical material. The agglutination test on slides was carried out on this strains using Mangifera indica extract of own production. Agglutinating preparation obtained from the seeds of M. indica agglutinated Y. enterocolitica organisms possessing the pVY plasmid and CRMOX+ phenotype in dilutions to 1.56 micrograms/ml. In identification tests conducted parallelly agglutination solution was used in concentrations of 100 and 10 micrograms/ml. All clones of Y. enterocolitica from O3 group from cultures at 37 degrees C and with CRMOX+ phenotype possessing the pVY plasmid were agglutinated by the extract. Agglutination failed to develop in the cultures of these clones incubated at 25 degrees C. Yersinia clones not containing the pVY plasmid with CRMOX- phenotype were resistant to agglutination. The virulence plasmid was found in 44 out of 75 strains of Y. enterocolitica O3 and was identified by restriction analysis after plasmid DNA digestion with Eco RI enzyme. The obtained results agreed with those of Wauters et al. in 1995 and confirmed the opinion of these authors on the usefulness of the test with M. indica agglutinin for the identification of virulent Y. enterocolitica strains.

[Characteristics of Yersinia strains from clinical material and from other sources. I. Selected biochemical properties]. / Charakterystyka szczepów z rodzaju Yersinia pochodzacych z materialu klinicznego i innych zródel. I. Wybrane wlasciwosci biochemiczne.

The purpose of the study was the determination of biochemical features of strains belonging to Yersinia genus isolated from clinical material and other sources, and an assessment of the usefulness of certain biochemical tests for the detection of potentially pathogenic Yersinia strains. In all, 110 strains were studied, including 48 from the archives of the National Institute of Hygiene, 38 isolated from food of animal or plant origin, and 24 isolated from blood and faeces of patients. On the ground of the biochemical features the isolated strains were recognized as belonging to 5 species: Y. enterocolitica(83 strains), Y. pseudotuberculosis(12 strains), Y. frederiksenii(7 strains), Y. kristensenii(2 strains) and Y. intermedia(4 strains). Two strains differed in their features from the typical species reveale as yet in Yersinia genus. All strains isolated from clinical material were recognized as Y. enterocolitica, while those isolated from food included also Y. frederiksenii, Y. intermedia and Y. kristensenii. The isolated strains grew well on CIN medium forming characteristic violet-pink colonies with irregular outlines after 24-48 hours of incubation at 25 degrees C or 37 degrees C. The potential pathogenicity was assessed on the basis of the presence of autoagglutination (AA) and absent ability of breaking down of salicin, aesculin and pyrazinamide. Only two strains of Y. enterocolitica 03 isolated from faeces and 5 strains of Y. pseudotuberculosis from the archives had AA ability. Low frequency of AA was explained with possible loss of plasmids conveying virulence as a result of multiple passages of the strains, and the fact that many of them were present in the R phase. All strains of Y. enterocolitica 03 and both Y. enterocolitica 09 strains from the archives could be assumed to be potentially pathogenic for man and animals, while no strain isolated from food showed the set of features which could suggest its possible pathogenicity.

[Evaluation of the usefulness of the latex test for detection and identification of O-antigens of Yersinia enterocolitica and Yersinia pseudotuberculosis]. / Ocena przydatnosci odczynu lateksowego do wykrywania i identyfikacji o antygenów paleczek Yersinia enterocolitica i Yersinia pseudotuberculosis.

In the study latex reagents of own production were used, in which latex of 0.9 microns particle diameter was coated with globulins salted out from rabbit sera against Y. enterocolitica groups 03, 05, 06, 08 and 09, and Y. pseudotuberculosis groups I and III. The study was carried out with five standard strains of Y. enterocolitica representing groups 03, 05, 06, 08 and 09, two standard strains of Y. pseudotuberculosis representing group antigens I and III, and 110 strains identified as Yersinia organisms, including 83 strains of Y. enterocolitica, 12 - Y. pseudotuberculosis, 7 - Y. frederiksenii, 4 - Y. intermedia, 2 - Y. kristensenii, and 2 strain of unknown species. Besides that, 54 laboratory strains of Enterobacteriaceae not belonging to Yersinia genus were studied. Latex test was done with bacterial suspensions of 6 x 10(8) cell/ml density of standard Yersinia strains and laboratory strains of Enterobacteriaceae, and with 110 Yersinia strains cultured in broth and peptone water media with tryptophan 0.1%. It was found that the prepared latex reagents reacted in the agglutination test on slide only with the suspensions of homologus. Yersinia organisms but not with suspensions of other Enterobacteriaceae. Among 83 strains identified as Y. enterocolitica 24 belonged to group 03, 19 to 05, 10 to 06, 2 to 08, 2 to 09. In the 12 strains identified as Y. pseudotuberculosis 9 belonged to group I and 2 to group III. The study showed that the latex reagents prepared by us can be used for identification of O-antigen of Yersinia organism immediately in liquid media.

[Occurrence of virulent plasmids in strains of Yersinia obtained from various sources]. / Wystepowanie plazmidów wirulencji w szczepach paleczek Yersinia pochodzacych z róznych zródel.

By the method of alkaline lysis the occurrence was studied of plasmid DNA in 122 strains of Yersinia. In 29 strains a single plasmid was found with characteristic growth of the organism on CRMOX (CRMOX+) medium. These features are encoded by genes located on the pYV virulence plasmid. The group of Yersinia strains possessing the virulence plasmid included 27 strains of Y. enterocolitica 0:3 isolated from clinical materials, among them 21 strains isolated from patients between January and September 1996, while the remaining two strains with the virulence plasmid belonged to Y. pseudotuberculosis antigenic group I. Following restriction analysis with the EcoRI enzyme of the virulence plasmids isolated from 27 strains of Y. enterocolitica 0:3 occurrence of only one restriction endonuclease pattern agreeing with the virulence plasmid pattern of Y. enterocolitica 0:3 strains reported in the literature was found in all strains. On the other hand, the restriction analysis of the virulence plasmids obtained from Y. enterocolitica 0:3 and Y. pseudotuberculosis I strains showed evident differences between these plasmids in the size of the particle and the restriction pattern. The plasmid size calculated on the basis of the analysis of the restriction endonuclease patterns for virulence plasmids isolated from the strains of Y. enterocolitica 0:3 and Y. pseudotuberculosis I was 71.5 thousands and 62.7 thousands of base pairs respectively, and was in the range 60-75 thousands bp (40-50 Mda) reported in the literature for virulence plasmids of Yersinia. The study showed that finding of characteristic growth of Yersinia organisms on the CRMOX medium can be useful for the detection of strains containing the pYV virulence plasmid and for the determination of their potential pathogenicity.

[Evaluation of results for controlling the variability of diagnostic tests for intestinal bacteria introduced to the laboratories of sanitary-epidemiologic stations in 1995]. / Ocena wyników kontroli wiarygodnosci diagnostycznych badan w kierunku paleczek jelitowych przeprowadzonej w laboratoriach stacji sanitarno-epidemiologicznych w 1995 roku.

In this testing bacteriological laboratories of 49 epidemiological stations were participating. Eleven control tests were prepared in form of lyophilize faecal samples containing three different organisms in each sample with pathogenic organisms present in each of 10 tests (a different species in each test) along with a non-pathogenic Enterobacteriaceae strain, while the 11th test contained only organisms belonging to physiological intestinal flora. Each laboratory received two different tests for doing them. The following bacterial strains were used S. oranienburg var, lac+ S. muenster, S. infantis, S. sonnei, S. flexneri, A. hydrophila, Y. enterocolitica, E. coli 018, E. coli 026, E. coli 0124, and as accompanying organisms: C. freundii var lac+ and lac-, P. mirabilis and H. alvei. Among 49 participating laboratories 31 (63.3%) detected the etiological infectious agent in both samples, or its absence was shown in the 11th test. In 23 laboratories (46.9%) the cultured organisms were species-grouped or their serological type was established, in the remaining 8 laboratories (16.3%) the identification was incomplete or serological type was not correctly recognized. In 15 laboratories (30.6%) the infectious agent was found in only one test, and in 12 of these laboratories (25.5%) the cultured organism were identified correctly completely, and in 3 (6.1%) identification was incomplete or serological type was not correctly recognized. In 3 (6.1%) among 49 laboratories the infectious agent was not found in any test. The study made possible an insight into the reliability of the diagnostic tests for Enterobacteriaceae carried out in the sanitary-epidemiological stations. The use of faeces-simulating samples made possible to assess not only the correct identification of the isolated organisms, but also to trace the course of the diagnostic management used in each laboratory for testing of faeces samples.

[Comparative evaluation of latex reagents of Wellcolex Color Salmonella and Latex Salmonella used for detection and identification of Salmonella rods]. / Porównawcza ocena zestawów lateksowych Wellcolex Colour Salmonella i Lateks Salmonella sluzacych do wykrywania i identyfikacji somatycznych antygenów paleczek z rodzaju Salmonella.

The aim of this study is to compare the sensitivity and specificity of the Wellcolex Colour Salmonella (WCS) set produced by Murex with the Latex Salmonella (LS) set developed by the Polish company Biomex and commonly used in sanitary and epidemiological stations. An attempt is also made to determine the possible usefulness of the WCS test in routine diagnostic of salmonellosis and of S. typhi carrier. The sensitivity and specificity of latex reagents of both sets were determined basing on reactions with the suspensions of 17 selected Salmonella strains representing the A-E and G serological groups and with Salmonella O antigen preparations obtained using the Boivin method. Both reagents from the WCS set were found to detect Salmonella bacteria in a suspension having a minimal density of 7.5-60 x 10(7) cfu/ml while both the polyvalent reagent B-E and monovalent reagents from the LS set still reacted with suspensions of 0.47-15 x 10(7) cfu/ml density. Comparison of the sensitivity of both tests basing on reactions with Salmonella O antigen specimens from the B to E groups revealed that the latex reagents from the two sets detected antigens from the C2 and C3 groups and the E group in concentrations of 1 microgram/ml and 0.5 microgram/ml respectively. In the case of antigen specimens from group B, group C and group D, the LS test detecting these antigens in concentrations of 0.25-1 microgram/ml turned out to be four to eight times more sensitive in reaction with a polyvalent agent and two to eight times more sensitive in reaction with monovalent reagents than the WCS set. The evaluated latex reagents from the WCS set and LS set reacted specifically with both cell suspensions and Salmonella antigen preparations. Also, the applicability of the two latex sets to detect and identify Salmonella antigens in liquid and mixed bacterial cultures of these germs in selenite broth was compared. A positive result of the WCS test was obtained in 41% of Salmonella culture samples whereas Salmonella antigens were found in all the studied culture samples when the polyvalent reagent B-E from the LS set was used and in 97.5% of the samples when monovalent reagents were used. The study showed that in spite of the comparable specificity of the WCS test with respect to the LS set produced in Poland, the latex reagents from the WCS set turned out to be of little use in detecting and identifying Salmonella antigens in mixed bacterial cultures in selenite broth.

[Identification of enteropathogenic strains of E. coli (EPEC) by application of the latex test. I. Evaluation of specificity and sensitivity of the test]. / Identyfikacja enteropatogennych szczepów E. coli (EPEC) przy zastosowaniu testu lateksowego. I. Ocena swoistosci i czulosci testu.

The study was aimed at elaboration of the test and evaluation of specificity and sensitiveness of it during routine diagnosis and detection of enteropathogenic strains of E. coli (EPEC), basing on direct identification of O antigen of these bacteria. The studies was performed by application of polystyrene latex having particles of 0.8 micron in diameter and coated with rabbit globulins immune for O antigens of 14 serotypes of E. coli identified in Poland as EPEC strains. Fourteen univalent reagents and three multivalent reagents (identifying 4-6 group antigens) were used. Latex reagents, prepared by own method, reacted only with suspensions of homologous strains of E. coli, not agglutinating in presence of O antigens of remaining EPEC strains. Evaluating specificity of univalent reagents against suspensions of bacteria representing 111 other than EPEC strains of E. coli, it was found that only in 5 cases agglutination did occur in presence of heterologous cell suspensions. These reactions concerned strains representing 03, 04, 010, 090 and 0106 group antigens. Comparative studies performed with latex and slide agglutination tests and OK sera on 391 freshly isolated samples of feces of children (determined in regional laboratories as EPEC) have shown that as a results of serological reidentification of these strains with commercial OK sera for 14 serotypes of EPEC, positive result of agglutination test was obtained only with 277 (70.8%) of strains. These results suggest a possibility of application of latex reagents for detection of EPEC strains basing on identification of O antigen of these bacteria.

[Evaluation of usefulness of a new generation of tests for detection in humans of antibodies for 9,12 antigens of Salmonella. I. Occurrence and level of antibodies detected by DOT-ELISA, latex and passive hemagglutination tests]. / Ocena przydatnosci testów nowej generacji do wykrywania u ludzi przeciwcial dla antygenu 9, 12 paleczek Salmonella. I. Wystepowanie i poziom przeciwcial wykrywanych odczynami DOT-ELISA, lateksowym i hemaglutynacji biernej.

The study was aimed at evaluation of usefulness of immunoenzymatic Dot-ELISA test and an own latex test (OL) for diagnosis of infections evoked by group D Salmonella in humans with application of passive hemagglutination test (OHS) as a relation test. Samples of blood donors, persons suspected of infection with group D Salmonella and of patients with acute gastroenteritis, were tested. In highest percentage of tested samples of serum derived from blood donors (84.5%), antibodies for 9, 12 antigen with Dot-ELISA were detected in immunoglobulin G class. In class IgM these antibodies were found in 46.5% of tested samples, whereas in IgA class only in 11.9% of samples. By application of passive hemagglutination, antibodies against 9, 12 antigen were detected in 56.8% of serum samples from blood donors and by application of a latex test in 8.7% of samples. Evaluation of antibody level of somatic antigen of group D Salmonella in healthy people formed a basis for determination for each of tests of a borderline serum titer accepted as diagnostically significant for specific antigenic stimulation. It permitted for analysis of variability of differences between the level of antibodies for 9, 12 antigen determined in blood donor serum and in patients from other two groups. By all three tests antibodies for 9, 12 antigen were detected significantly more frequently than in blood donors only in samples from patients suspected of Salmonella D infections. In highest percentage of samples (80.4%) these antibodies were detected by the Dot-ELISA test in IgM and IgG classes, slightly lower in OL (70.7% of samples) and in lowest in OHB (57.4% of samples). In samples of serum from patients with acute gastroenteritis, antibodies against 9, 12 antigen were found significantly more frequently than in blood donors only by the Dot-ELISA test in all classes of immunoglobulins (IgM-87.4%, IgA-56.2% and IgG-62.5% of serum samples).