Use of an artificial antigen simulating the Salmonella O-determinant 4 for determining antibodies to Salmonella group B O-antigen in immunoenzyme analysis

The use of the artificial antigen abequosylmannoside copolymer with acrylamide in the enzyme immunoassay for the determination of antibodies in the sera of salmonellosis patients has enhanced the specificity of the serological diagnosis of group B salmonellosis in comparison with the use of the natural antiren, S. typhimurium lipopolysaccharide.     

Metabolic transformation affected by specific Salmonella O antigen in the lymphocytes of salmonellosis patients

Metabolic transformation in the lymphocytes of salmonellosis patients, manifested by changes in the proportion of nucleic acids due to the stimulating action of Salmonella specific O antigen, was studied by the method of microspectral luminescent analysis. The level of single-helix nucleic acids in lymphocytes was shown to increase 6-8 hours after the stimulating action of specific O antigen, which was manifested by the increase of the alpha parameter from 0.21 to 0.68 in salmonellosis patients. This made it possible to confirm the diagnosis of salmonellosis in 92-95% of cases even at the early period of the disease when serodiagnosis could not yet be made.     

Comparison of the diagnostic value of methods for determining antibodies against the Salmonella group-B O-antigen

The analysis of serum samples from 124 patients with the bacteriologically confirmed diagnosis of group B salmonellosis has revealed that the specific neutralization variant of the enzyme immunoassay (EIA) makes it possible to detect IgA, IgG and IgM more effectively than the indirect EIA variant and the passive hemagglutination test.     

Fatal case of salmonellosis (Salmonella pullorum) in a chimpanzee (Pan troglodytes) in the Jos Zoo

A case of salmonellosis in a captive chimpanzee (Pan troglydytes) is reported. Confirmatory diagnosis was based on clinical signs, necropsy and histopathological examination, and the isolation of Salmonella pullorum from the lung, liver, kidney and intestines of the animal. The source of infection was not ascertained.     

Invasive Salmonellosis among Children Admitted to a Rural Tanzanian Hospital and a Comparison with Previous Studies

Background

The importance of invasive salmonellosis in African children is well recognized but there is inadequate information on these infections. We conducted a fever surveillance study in a Tanzanian rural hospital to estimate the case fraction of invasive salmonellosis among pediatric admissions, examine associations with common co-morbidities and describe its clinical features. We compared our main findings with those from previous studies among children in sub-Saharan Africa.

Methodology/Principal Findings

From 1 March 2008 to 28 Feb 2009, 1,502 children were enrolled into the study. We collected clinical information and blood for point of care tests, culture, and diagnosis of malaria and HIV. We analyzed the clinical features on admission and outcome by laboratory-confirmed diagnosis. Pathogenic bacteria were isolated from the blood of 156 (10%) children, of which 14 (9%) were S. typhi, 45 (29%) were NTS and 97 (62%) were other pathogenic bacteria. Invasive salmonellosis accounted for 59/156 (38%) bacteremic children. Children with typhoid fever were significantly older and presented with a longer duration of fever. NTS infections were significantly associated with prior antimalarial treatment, malarial complications and with a high risk for death.

Conclusions/Significance

Invasive salmonellosis, particularly NTS infection, is an important cause of febrile disease among hospitalized children in our rural Tanzanian setting. Previous studies showed considerable variation in the case fraction of S. typhi and NTS infections. Certain suggestive clinical features (such as older age and long duration of fever for typhoid whereas concomitant malaria, anemia, jaundice and hypoglycemia for NTS infection) may be used to distinguish invasive salmonellosis from other severe febrile illness.     

Recurrent bacteraemia caused by different Salmonella species in a systemic lupus erythematosus patient

Non-typhoidal Salmonella infections are increasingly being encountered. Recurrent systemic salmonellosis has previously been reported in both immunocompromised and immunocompetent hosts. However, recurrent salmonella bacteraemia by different species of salmonella has rarely been described. We report a patient with systemic lupus erythematosus having Salmonella enteritidis and Salmonella typhimurium infections after ingesting raw eggs and vegetables. Multiple internal organs, including left knee joint, left ovary and bones, were involved. The patient recovered with a prolonged course of antibiotics. This case illustrates that recurrent systemic salmonellosis can be caused by different species of pathogens, especially in immunocompromised hosts. Detailed food history and education on food hygiene is essential in making the diagnosis and preventing recurrence. A prolonged course of antibiotics may be needed to manage these cases.     

Systemic candidiasis with meningeal involvement in a newborn infant

The newborn with sepsis (E. coli) and salmonellosis was described. After treatment with broad-spectrum antibiotics it was suffered from Candida albicans (Meningitis with Hydrocephalus internus, Chorioretinitis and Ostitis). The authors difficulties connected with diagnosis and anti-fungal therapy have showed. They have punctated the necessity of combined anti-mycotic therapy.     

Results of an epidemiological study of familial foci of salmonellosis in the Western Urals

The study of 449 family foci of salmonellosis demonstrated the possibility of detecting cases of salmonellosis, not diagnosed by clinical and bacteriological methods, in the passive hemagglutination test. Such undetected Salmonella carriers, not observing the rules of personal hygiene, contributed to the contamination of household articles, foodstuffs and the environment. The formation of the family foci of salmonellosis was facilitated by the belated detection and hospitalization of salmonelloses cases, as well as by the inadequate observance of the rules for infant care and feeding.     

Climate variations and salmonellosis transmission in Adelaide,South Australia: a comparison between regression models

This is the first study to identify appropriate regression models for the association between climate variation and salmonellosis transmission. A comparison between different regression models was conducted using surveillance data in Adelaide, South Australia. By using notified salmonellosis cases and climatic variables from the Adelaide metropolitan area over the period 1990–2003, four regression methods were examined: standard Poisson regression, autoregressive adjusted Poisson regression, multiple linear regression, and a seasonal autoregressive integrated moving average (SARIMA) model. Notified salmonellosis cases in 2004 were used to test the forecasting ability of the four models. Parameter estimation, goodness-of-fit and forecasting ability of the four regression models were compared. Temperatures occurring 2 weeks prior to cases were positively associated with cases of salmonellosis. Rainfall was also inversely related to the number of cases. The comparison of the goodness-of-fit and forecasting ability suggest that the SARIMA model is better than the other three regression models. Temperature and rainfall may be used as climatic predictors of salmonellosis cases in regions with climatic characteristics similar to those of Adelaide. The SARIMA model could, thus, be adopted to quantify the relationship between climate variations and salmonellosis transmission.     

Protective immunity induced by porin in experimental mouse salmonellosis

The induction of protective immunity to mouse salmonellosis by porin from Salmonella typhimurium LT2 was studied. The immunization with porin induced a high level of protective immunity to salmonellosis in BALB/c mice. Mice immunized with porin exhibited significant levels of delayed-type hypersensitivity response and interleukin-2 production, indicating that porin was capable of inducing cell-mediated immunity (CMI). Furthermore, we found that both T cells and sera taken from the porin-immunized mice could transfer the protection against salmonellosis into nonimmunized mice. These observations suggested that a high level of the protection to salmonellosis obtained by the porin immunization resulted from the induction of CMI in addition to humoral immunity.     

Effects of interferon preparations on the course of Salmonella infection (experimental and clinical studies)]

The effect of type I interferons on the process of experimental salmonellosis in mice and rabbits, as well as their effect on salmonellosis in patients was studied. It was shown that homologous interferon increased the animal survival rate, activated bactericidal activity of the phagocytic cells and increased elimination of the infectious agents from the host. The complex of the etiotropic and pathogenetic treatment of 32 patients with salmonellosis included human leukocytic interferon, leukinferon. It was administered intramuscularly in a dose of 1 x 10(4)-2 x 10(4) IU: three injections at intervals of 48 to 72 hours (the treatment course). The course was repeated 10 days after the last injection of the first course. Addition of leukinferon to the routine scheme of the medicinal treatment of salmonellosis provided recovery of all the patients without complications or appearance of the bacteria carriers (the observation period of more than 3 years).     

Significance of Salmonella serovars and the biological properties of the causative agents in the epidemic process in salmonelloses

Analysis of the manifestations of the epidemic process of Salmonella infections with regard to the serovar and biological properties of salmonellae has made it possible to find out the specific epidemiological properties of salmonellosis caused by S. typhimurium and to suggest that under present-day conditions salmonellosis of this etiology frequently acquires the features of a human disease, which is necessary to take into consideration in planning the measures for controlling these infections.     

Antibiotic therapy of Salmonella infection in infants during the first year of life and methods if its correction]

The efficacy of antibiotic therapy of salmonellosis was studied and functional activity of peripheral blood leukocytes from electron microscopic data was estimated in 200 infants. It was shown that the use of antibiotics in combination with immunostimulants such as leukocyte mass, lysozyme and prodigiozan in complex therapy of salmonellosis in infants had a favourable effect on both the time course of the clinical signs and the functional state of the neutrophil leukocytes. The duration of the treatment decreased by 6.14 +/- 0.34 days and repeated isolation of the pathogen from the host appeared to be less frequent.     

A comparative analysis of the properties of bacteria in the genus Salmonella isolated from children in Latvia]

Since social and economic changes in Latvia in 1991 the incidence of salmonellosis dramatically increased: more than 500 pediatric cases are registered every year. Specification of the properties of the Salmonella strains isolated in Latvia was undertaken. The study demonstrated that acute salmonellosis in pediatric inpatients was mainly due to S.typhimurium (78 per cent) and only in 22 per cent of the patients it was due to S.enteritidis. All the S.typhimurium isolates showed high antibiotic resistance defined by specific extended spectrum beta-lactamase (CTX-M-5).     

Epidemiology of Salmonellosis in Garden Birds in England and Wales, 1993 to 2003

Salmonellosis has been reported as an important cause of mortality of garden birds in several countries, including Norway and Scotland. We investigated the frequency of the disease in garden birds submitted for postmortem examination by members of the public in England and Wales between 1993 and 2003, inclusive. We found salmonellosis to be the most frequent cause of death due to infectious disease in the garden birds submitted. This disease was confirmed in 7 of the 45 bird species that were examined postmortem, with the greenfinch (Carduelis chloris) and the house sparrow (Passer domesticus) most frequently affected. Salmonella Typhimurium definitive phage type (DT) 40, DT56 variant(v), and DT160 accounted for the majority of isolates. Salmonellosis incidents chiefly occurred in the English Midlands, the English/Welsh border region, and southern England. Variation in the temporal and spatial distribution of the phage types occurred over the study period. While birds were examined throughout the year, there was a marked winter seasonality in salmonellosis. A significant sex bias was observed in affected greenfinches, with males more frequently diagnosed with salmonellosis than females. No sex bias was observed for other affected species. Further research is required to determine if salmonellosis is an important constraint to the populations of affected species and if disease outbreaks are driven by human factors, such as provisioning.     

Immunomodulating properties of various microbes--representatives of normal intestinal microflora]

The impact of oral administration of heat-killed bifidobacteria, lactobacteria, enterococci and bacteroides on mouse resistance to experimental salmonellosis and content of immunoglobulin-synthesizing cells in the proper plate of the small intestine was studied. It was shown that the administration of the killed bifidobacteria, lactobacteria and enterococci increased the animal resistance to experimental salmonellosis infection and induced an increase in the content of immunoglobulin-synthesizing cells in the proper plate of the small intestine. The administration of the killed bacteroides had no such effect. Possible development of bacterial preparations with immunomodulating properties based on killed bifidobacteria, lactobacteria or enterococci is discussed.     

In vivo and in vitro studies of genetic resistance to systemic salmonellosis in the chicken encoded by the SAL1 locus

A number of inbred lines of chickens have been shown to be resistant or susceptible to systemic salmonellosis caused by Salmonella enterica serovar Gallinarum in adult birds, or by S. enterica serovar Enteritidis and S. enterica serovar Typhimurium in young chicks. Resistant lines show only moderate pathology and low mortality rates, whereas susceptible lines display extensive pathological changes and higher levels of mortality following Salmonella infection. Genetic resistance to salmonellosis is dominant and not linked to sex, MHC or Slc11a1 (formerly known as Nramp1), which leads to resistance in mice and other species. A novel locus encoding resistance to salmonellosis has been identified on chicken chromosome 5, and designated SAL1. The nature of the differences in pathology found between resistant and susceptible chicken lines in vivo indicates that resistance is expressed at the level of the mononuclear phagocyte system. Macrophages from adult resistant line birds cleared Salmonella serovar Gallinarum from infected macrophages within 24 h, whereas Salmonella bacteria persisted within macrophages from susceptible line birds for at least 48 h. Clearance of Salmonella by macrophages was accompanied by a strong and reproducible respiratory burst response in resistant lines, but little or no response in susceptible lines. Macrophages from an outbred chicken line showed variable responses. No differences were seen in macrophage nitric oxide production in cells from resistant or susceptible lines. These differences suggest that increased macrophage antimicrobial activity correlates with resistance and that macrophage activity plays an important role in genetic resistance to systemic salmonellosis in the chicken.     

An immunohistochemical analysis of local immunity in Salmonella and dysenteric infections]

Immunohistochemical analysis was performed in 21 patients with acute and chronic dysentery, in 32 patients with different forms of salmonellosis in comparison with the cytoenzymatic status (CES) of immunocytes in the mucous membrane of the large intestine. It has been revealed that for acute dysentery the activation of the cellular and humoral links of local immunity is typical, but for salmonellosis--mainly of the humoral one. The chronic processes in dysentery and salmonellosis are connected with the increase in the subpopulation of T8-suppressors. Immunohistochemical data correlate completely with CES of immunocytes and that allows one use them with prognostic purposes.     

Relationship of the Frequency of Isolation of Salmonellae to Their Resistance to Drying and Freezing

The resistance of different Salmonella serotypes to drying and freezing has been shown to be related to their incidence in salmonellosis.     

The pathogenicity of Salmonella mbandaka in specific pathogen free rabbits

Salmonella mbandaka was isolated from the lungs of three rabbits that developed a peracute disease and died three to eight weeks following extensive experimental manipulation. To examine the pathogenicity of this rare serotype, clinically normal, S. mbandaka-carrier rabbits were subjected to either corticosteroid immunosuppression alone or corticosteroid immunosuppression with a minor surgical procedure. Acute or peracute salmonellosis developed in one of two rabbits immunosuppressed only, and in three of four rabbits immunosuppressed and surgically manipulated. Stressful experimental procedures may precipitate episodes of clinical salmonellosis in rabbits harboring this organism. Salmonella mbandaka, should be considered a zoonotic agent in the laboratory environment.