Long-term yersiniosis surveillance project in Czechoslovakia

The paper presents an epidemiological analysis of 8,232 cases of yersiniosis caused by Y. enterocolitica 03 over 1972-1988 as reported by Hygienic Stations. The steady epidemiological characteristics of yersiniosis were the prevalence of children and boys and a typical seasonal pattern with differences between the Czech and Slovak Republics. In the Czech Republic, there were several incidence peaks following, when summarized, the incidence curve of other alimentary infections, whereas in the Slovak Republic morbidity reached its peak during winter months. The numbers of isolated strains oscillated significantly between districts and by years. It appears that the number of positive findings in different districts is not only an objective value reflecting a mosaic-like pattern of incidence but also depends on the quality of microbiological diagnostics.     

Occurrence of Helicobacter pylori specific antigens in diseases of gastrointestinal tract

The results of the immunophoretic analysis of H. pylori antigenic structure are presented. Along with H. pylori O-antigen, specific surface antigen of acidic nature, relatively thermolabile with characteristics similar to those of K-antigens, was detected. A diagnosticum based on the coagglutination test for the rapid detection of H. pylori specific antigens in the patients' biological fluids (coprofiltrate, saliva) by the noninvasive method was developed. The circulation mode of H. pylori in human body and its correlation with the clinical symptoms of the disease was shown. H. pylori antigens were very frequently detected (in 65 - 83% of cases) in patients with acute bacterial enteric infections: shigellosis, salmonellosis, yersiniosis, campylobacteriosis. The newly developed method seems to be promising for the rapid diagnosis of H. pylori associated infections, for the prolonged monitoring and evaluation of the effectiveness of antibacterial therapy.     

The intensity of cell receptor catabolism in intestinal yersiniosis and pseudotuberculosis

The intensity of the catabolism of cell receptors in yersiniosis was evaluated by the level of R-proteins in the blood sera of 95 patients. The study revealed that the degree of an increase in the level of R-protein depended on the severity and the course of the pathological process was the same in both nosological forms of the disease. The high and stable level of R-proteins was indicative of the possibility of the prolonged and relapsing course of yersiniosis.     

Effects of dietary probiotic supplementations on prevention/treatment of yersiniosis disease

Aims:  To evaluate Enterobacter cloacae and Bacillus mojavensis , isolated from rainbow trout gut in the present study, as a probiotic to control yersiniosis disease.
Methods and Results:  A strain of Ent. cloacae and B. mojavensis , isolated from the digestive tract of rainbow trout had an antagonistic effect to Yersinia ruckeri , which causes yersiniosis. After feeding fish with 1 × 10⁸ cells g⁻¹ probiotic containing feed for 60 days, the fish survival rate increased to 99·2% following challenge with Y. ruckeri compared with controls that had 35% survival rate. Effects of Ent. cloacae and B. mojavensis on weight gains and stimulation of red blood cells, white blood cells, platelets and hemoglobin were also evaluated in separate groups of fish fed probiotic containing feed for 2 months. Probiotic significantly affected white blood cells, hemoglobin and weight gains of the experimental fish.
Conclusions:  Enterobacter cloacae and B. mojavensis , can be used to prevent and control yersiniosis disease.
Significance and Impact of the Study:  In conclusion, concomitant use of Ent. cloacae and B. mojavensis as a feed supplement is beneficial to rainbow trout. Use of these organisms can protect fish from yersiniosis and enhance digestibility and utilization of feed. Use of such probiotics may also limit the use of antibiotics and other chemicals in control and treatment of diseases, and thus contribute to the effort to reduce environmental contamination by residual antibiotics and chemicals .     

Clinicoimmunological monitoring of therapy in patients with associated forms of yersiniosis

Characteristics of the clinical process and immunological profile in children with yersiniosis as a monoinfection or in association with acute intenstinal infections and virus hepatitis A are presented. The efficacy of the immunotropic therapy with cycloferon, an interferon inductor, and recombinant interferon in the patients with the viral and bacterial association of the disease (yersiniosis + hepatitis A) and initial disbalance of the serum cytokines was estimated. Dependence of the interferon clinicolaboratory efficacy on the initial levels of serum y-interferon, IL2 and IIA, promoting shorter terms of hyperthermia, diarrhea syndrome and cytolysis syndrome was shown. It allowed to optimize the scheme of the pathogenetic therapy of Yersinia mixed infection.     

Application of released proteins (RPs) of Yersinia enterocolitica for serological diagnosis of yersiniosis. II. Gene recombination for production of the YopD protein

The aim of this study was to evaluate the usefulness of gene recombination technique using the pET-30 Ek/LIC expression vector for production a 36 kDa released protein called YopD and evaluate of this purified protein as antigen in serodiagnosis of yersiniosis. Protein YopD of Y. enterocolitica was expressing in Escherichia coli BL21 (DE3) using the pET-30 Ek/LIC expression vector. Purification of the expressed enzyme from suspensions of E. coli cells treated with Bug Buster Protein/Extraction Reagent was accomplished by immobilised metal (Ni2+) affinity column chromatography (His-trap). The IgM, IgG and IgA class antibodies to YopD were measured in 100 serum samples collected from patients suspected for yersiniosis and 100 blood donors. The obtained results were compared to the results of ELISA with released proteins isolated from the culture of Y. enterocolitica supernatant under calcium deficient conditions and commercial ELISA with recombinant released proteins. A very high (94.0-100.0%) specificity and good sensitivity (55.2-80.4%) were displayed by the ELISA with YopD in relation to other two ELISA. The results of our study showed that recombinant YopD protein purified by chromatography of bio-affinity may be used in serodiagnosis of yersiniosis as a high specific antigen free of Yersinia lipopolysaccharides.     

Development of immunoreagents for the diagnostics of intestinal yersiniosis by antigen-binding lymphocytes

To diagnose intestinal yersiniosis, the detection of antigen-binding lymphocytes (ABL) with respect to Y. enterocolitica O3, O5 and O9 is proposed. Experiments on the immunization of rabbits with Y. enterocolitica LPS of these serovars revealed that immunoreagents, according to the data of cross antigen-dependent rosette formation and its inhibition, had species specificity (ABL of rabbits immunized with Y. enterocolitica did not interact with Salmonella, Shigella and Y. pseudotuberculosis antigens) and serovar specificity. Cross reactions in the detection of ABL by means of specific Y. enterocolitica O9 and Brucella melitensis immunoreagents in rabbits immunized with Y. enterocolitica were absent during the first days and could be detected only of day 25 after the injection of the immunogen. The method for the detection of ABL with the use of newly developed reagents could be used in clinics for the diagnostics of intestinal yersiniosis.     

Yersiniosis in free-ranging muskoxen on Banks Island, Northwest Territories, Canada.

Sixty-seven muskox (Ovibos moschatus) carcasses, 53 skeletal remains and two sick muskoxen were seen during an aerial survey of the Thomsen River region, northern Banks Island, Northwest Territories, Canada in late July 1986. Complete necropsies were performed on 29 muskoxen estimated to have died within the previous 3 to 5 days. Twenty were diagnosed with acute yersiniosis due to Yersinia pseudotuberculosis serotype 1B and were in excellent body condition. A diagnosis could not be made on seven animals due to marked autolysis; however, these muskoxen also were in excellent body condition. The remaining two were aged, emaciated muskoxen. This report describes the first occurrence of yersiniosis in free-ranging muskoxen and the first documentation of large scale mortality due to this disease in a free-ranging population of wild ungulates.     

Molecular epidemiology of Yersinia enterocolitica infections

Yersinia enterocolitica is an important food-borne pathogen that can cause yersiniosis in humans and animals. The epidemiology of Y. enterocolitica infections is complex and remains poorly understood. Most cases of yersiniosis occur sporadically without an apparent source. The main sources of human infection are assumed to be pork and pork products, as pigs are a major reservoir of pathogenic Y. enterocolitica. However, no clear evidence shows that such a transmission route exists. Using PCR, the detection rate of pathogenic Y. enterocolitica in raw pork products is high, which reinforces the assumption that these products are a transmission link between pigs and humans. Several different DNA-based methods have been used to characterize Y. enterocolitica strains. However, the high genetic similarity between strains and the predominating genotypes within the bio- and serotype have limited the benefit of these methods in epidemiological studies. Similar DNA patterns have been obtained among human and pig strains of pathogenic Y. enterocolitica, corroborating the view that pigs are an important source of human yersiniosis. Indistinguishable genotypes have also been found between human strains and dog, cat, sheep and wild rodent strains, indicating that these animals are other possible infection sources for humans.     

Evaluation of touch-down real-time PCR based on SYBR Green I fluorescent dye for the detection of Neisseria meningitidis in clinical samples

Antibiotic treatment prior to transport or admission of patients to hospital has reduced the proportion of patients with invasive meningococcal disease (IMD) from whom Neisseria meningitidis can be isolated by standard microbiological techniques. Assays to detect the crgA gene were used to detect meningococcal DNA by both conventional polymerase chain reaction (PCR) and real-time PCR (RTPCR) in relation to microbiological diagnosis of cases over two years between 2002 and 2003. The sensitivity of both PCR assays for culture-confirmed cases was 93% and the specificity was 98.6%. Agreement between the two PCR assays was 96.2%. The inter- and intra-assay variations and effects of different amounts of DNA on the melting temperatures were examined. The touch-down RTPCR based on SYBR Green I fluorescent dye detected and characterized N. meningitidis in clinical samples within one hour.     

Use of an in vitro allergy test for the differential diagnosis of human brucellosis and yersiniosis

The degree of the allergic reorganization in the body of brucellosis and yersiniosis patients was determined by the study of their blood and serum samples in the in vitro allergy test (the direct and indirect leukocytolysis test). The allergy test is highly specific and recommended as a differential diagnostic method in brucellosis and yersiniosis infections.     

Evaluation of non-culture diagnosis of invasive meningococcal disease by polymerase chain reaction (PCR)

Antibiotic treatment prior to transport or admission to hospital has reduced the proportion of cases of invasive meningococcal disease (IMD) from which Neisseria meningitidis can be isolated by standard microbiological techniques. Identification of meningococci by polymerase chain reaction (PCR) was assessed in relation to microbiological diagnosis for cases over a 4-year period between 1998 and 2001. A screening assay for the IS1106 gene was used to detect meningococcal DNA and five additional assays for siaD and orf-2 genes were performed to determine the serogroup. PCR results were compared with results of bacteriological culture, other laboratory test results and clinical data. The sensitivity of the PCR assay for culture-confirmed cases was 98.5%. The specificity of the assay was 96% based on test results for patients from whom other bacteria were isolated, children with viral meningitis and afebrile negative controls. The siaD B/C/W-135 and Y as well as the orf-2 gene for serogroup A PCR assays were able to determine the serogroup for 75.2% of cases that were positive by PCR screening assay. When isolates from patients with IMD were tested by both agglutination and PCR, the results agreed in all cases. PCR is a useful tool for diagnosis of IMD when Gram stain and culture tests are negative due to antibiotic treatment prior to collection of samples for microbiological analyses.     

Utilization of released proteins (RPs) of Yersinia enterocolitica for serologic diagnosis of yersiniosis. III. Western-blot

The usefulness of the immunoblotting using released proteins (Yersinia outer proteins-Yop) as the antigen for the serological diagnosis of yersiniosis was estimated. The IgA, IgG, and IgM antibody responses of patients with yersiniosis and healthy blood donors were studied by western-blot prepared in our laboratory, and two commercial assays. The results indicate that antibodies of all three classes are most consistently directed against the proteins of YopD, YopM and YopE. Good correlations between the three western-blots were obtained for all proteins except the protein V-AG. Patients with yersinia-triggered reactive arthritis have IgA class antibodies against the YopD more often and for longer period than the non-arthritic patients with yersiniosis.     

Red-bellied tamarins (Saguinus labiatus): Hematologic reference values and hemopathologic responses

Hematologic reference values have been established for captive adult red-bellied tamarins (Saguinus labiatus) by carrying out full blood counts and fibrinogen estimations on 25 clinically normal animals. The only significant sex difference detected was in the reticulocyte count which was higher in females than in males. The reference values were used to identify abnormal changes in the blood of nine clinical cases. Hypochromic anemia, neutrophilia, and raised fibrinogen levels were found in animals with self-inflicted injuries, dermatitis, and ileocecal intussusception. Target cells and jaundiced plasma were noted in a case of yersiniosis. Two animals in which generalized muscle wasting was the main abnormal clinical sign were severely anemic, and in one of these cases a significant number of Heinz bodies was present. The findings in these two animals were compared with those in common marmosets (Callithrix jacchus) with possible wasting marmoset syndrome.     

Completeness of statutory notification for acute bacterial meningitis.

Several different sources of data, including statutory notifications, were used to identify cases of acute bacterial meningitis in childhood in a defined population. Only half the cases of meningococcal meningitis and less than one quarter of ofther types of bacterial meningitis had been notified. Notified cases differed from the remainder with respect to causative organism, age, outcome, and type of hospital of admission. Thus notifications are an unreliable measure of incidence for this disease, and studies of infectious disease based on notified cases alone should be interpreted with considerable reserve. It is suggested that infectious-disease surveillance should be both clinical and microbiological and that data from different sources need to co-ordinated. The reason for reporting each disease (or organism) should be specified and and reviewed periodically.     

Humoral response to selected antigens of Yersinia enterocolitica and Yersinia pseudotuberculosis in the course of yersiniosis in humans. I. Occurrence of antibodies to enterobacterial common antigen (ECA)

The antibodies against the Enterobacterial Common Antigen (ECA) were detected using the ELISA in 293 serum samples collected from 185 persons suspected for yersiniosis, as well as 115 serum samples from healthy individuals (blood donors). The presence of IgA antibody in diagnostically significant titres for ECA were detected by ELISA in 3.5%, IgG in 13.0%, and IgM in 5.2% of blood donors. Statistical analysis showed that the frequency of detecting antibodies for ECA among the patients with yersiniosis was significantly higher (p < 0.05) in relation to the blood donors. Most frequently the elevated antibody levels were detected among patients with reactive arthritis (IgA 29.2%, IgG 35.4%, IgM 16.7%) while the most infrequent among patients with abdominal pain in acute phase of yersiniosis (IgA 14.9%, IgG 25.3%, IgM 19.5%). The level of antibodies for ECA, together with age increased reaching its peak, on the average, among individuals aged 41 - 60 years. In majority of the individuals studied antibodies of the IgG class reached the level much higher in relation to those of the IgA and IgM classes. The obtained results showed that the detection of antibodies to ECA may be useful in serodiagnosis of Yersinia infections.     

Epizootiological evaluation of intestinal yersiniasis in Sakhalin Province

The work presents the data obtained as the result of the study of intestinal yersiniosis in the synanthropic and natural foci of the Sakhalin region. The circle of Yersinia carriers spreading this infection in the household and natural biocenoses has been established. For the first time the data on the water-type natural focus of yersiniosis with its specific spatial structure, detected on the Tyuleny Island, are published.     

A new chromogenic agar medium for detection of potentially virulent Yersinia enterocolitica

Several outbreaks of foodborne yersiniosis have been documented and this disease continues to be source of infections transmitted through foods. The selective agars most commonly used to isolate Yersinia enterocolitica in clinical, food and environmental samples, cefsulodin-irgasan-novobiocin (CIN) and MacConkey (MAC) agars, lack the ability to differentiate potentially virulent Y. enterocolitica from other Yersinia that may be present as well as some other bacterial spp. This study proposes the use of an agar medium, Y. enterocolitica chromogenic medium (YeCM), for isolation of potentially virulent Y. enterocolitica. This agar contains cellobiose as the fermentable sugar, a chromogenic substrate and selective inhibitors for suppression of colony formation by many competing bacteria. All strains of potentially virulent Yersinia of biotypes 1B, and biotypes 2-5 formed convex, red bulls-eye colonies on YeCM that were very similar to those described for CIN agar. However, Y. enterocolitica biotype 1A and other related Yersinia formed colonies that were purple/blue on YeCM while they formed typical red bulls-eye colonies on CIN agar. When a mixture of potentially virulent Y. enterocolitica biotype 1B, Y. enterocolitica biotype 1A and 5 other bacterial species was used to artificially contaminate tofu and then spread-plated on three selective agars, Y. enterocolitica biotype 1B colonies were easily distinguished from other strains on YeCM. However, Y. enterocolitica biotype 1B colonies were indistinguishable from many other colonies on CIN and only distinguishable from those of C. freundii on MAC. When colonies were picked and identified from these agars, typical colonies from YeCM were confirmed only as Y. enterocolitica biotype 1B. Typical colonies on CIN and MAC were found to belong to several competing species and biotypes.     

Possibility of the serological differential diagnosis of human brucellosis and yersiniasis

The results of the examination of patients with brucellosis and yersiniosis (serotype 0-9) are presented. The possibility of making, in principle, the differential serological diagnosis of brucellosis and yersiniosis in the agglutination test with the use of Yersinia OH-antigen has been established.