Potential infection of grazing cattle via contaminated water: a theoretical modelling approach.

Wastewater discharge and agricultural activities may pose microbial risks to natural water sources. The impact of different sources can be assessed by water quality modelling. The aim of this study was to use hydrological and hydrodynamic models to illustrate the risk of exposing grazing animals to faecal pollutants in natural water sources, using three zoonotic faecal pathogens as model microbes and fictitious pastures in Sweden as examples. Microbial contamination by manure from fertilisation and grazing was modelled by use of a hydrological model (HYPE) and a hydrodynamic model (MIKE 3 FM), and microbial contamination from human wastewater was modelled by application of both models in a backwards process. The faecal pathogens Salmonella spp., verotoxin-producing Escherichia coli O157:H7 (VTEC) and Cryptosporidium parvum were chosen as model organisms. The pathogen loads on arable land and pastures were estimated based on pathogen concentration in cattle faeces, herd prevalence and within-herd prevalence. Contamination from human wastewater discharge was simulated by estimating the number of pathogens required from a fictitious wastewater discharge to reach a concentration high enough to cause infection in cattle using the points on the fictitious pastures as their primary source of drinking water. In the scenarios for pathogens from animal sources, none of the simulated concentrations of salmonella exceeded the concentrations needed to infect adult cattle. For VTEC, most of the simulated concentrations exceeded the concentration needed to infect calves. For C. parvum, all the simulated concentrations exceeded the concentration needed to infect calves. The pathogen loads needed at the release points for human wastewater to achieve infectious doses for cattle were mostly above the potential loads of salmonella and VTEC estimated to be present in a 24-h overflow from a medium-size Swedish wastewater treatment plant, while the required pathogen loads of C. parvum at the release points were below the potential loads of C. parvum in a 24-h wastewater overflow. Most estimates in this study assume a worst-case scenario. Controlling zoonotic infections at herd level prevents environmental contamination and subsequent human exposure. The potential for infection of grazing animals with faecal pathogens has implications for keeping animals on pastures with access to natural water sources. As the infectious dose for most pathogens is more easily reached for calves than for adult animals, and young calves are also the main shedders of C. parvum, keeping young calves on pastures adjacent to natural water sources is best avoided.

Investigations and actions taken during 2011 due to the first finding of Echinococcus multilocularis in Sweden.

Echinococcus multilocularis is a parasite that can cause alveolar echinococcosis disease. After the first positive finding of E. multilocularis in Sweden in 2011, a consulting group with representatives from relevant authorities was summoned. In this group, all relevant information was shared, strategies for information dissemination and any actions to be taken due to the finding of E. multilocularis were discussed and decided. The present paper describes the actions taken during 2011 and the results thereof, including surveillance in animals, risk assessment for humans to become infected and recommendations given to the public. Further discussion about whether the parasite was introduced, and if so, how, as well as possible future development of the infection in animals and humans in Sweden and future actions are included.

Freedom from Echinococcus multilocularis: an Irish perspective.

Echinococcus multilocularis, an emerging zoonotic disease is extending its geographical distribution within the European Union (EU). At present, five member states including Ireland are considered free. Previous EU regulations on importing domestic pets allowed these countries to maintain national rules that required all dogs be treated with an anti-cestode compound before entry. The controls on the movement of pet animals within the EU were recently reviewed by the European Commission and it was decided that the five countries had to demonstrate freedom from E. multilocularis before they could continue with the mandatory tapeworm treatment. The intestines of 220, 307 and 216 foxes were examined, using the sedimentation and counting technique, for the presence of E. multilocularis in 2003, 2009 and 2010 respectively. There was no evidence of the parasite in the foxes. These data together with the negative results from 130 foxes examined by other workers during 1999 and 2000 (Wolfe et al., 2001) were used to estimate the probability of freedom using scenario trees. The result of the model suggested that the probability that Ireland was free from E. multilocularis in 2010 was high, 0.98 (95% confidence interval, 0.94-1.00), thus justifying the retention of the mandatory tapeworm treatment for dogs entering the country from other EU member states.

First detection of Echinococcus multilocularis in Sweden, February to March 2011.

Surveillance for the fox tapeworm, Echinococcus multilocularis, has been carried out in Sweden since 2000, with about 300 red foxes analysed annually. We report the first finding of E. multilocularis in Sweden, in a fox shot in December 2010 in the south-west of the country. A second infected fox shot in the same location was detected in March 2011. This paper describes the national monitoring programme and the ongoing work to estimate the prevalence and spread of the infection.

Source attribution of human Salmonella cases in Sweden.

The aim of this study was to identify the sources of sporadic domestic Salmonella cases in Sweden and to evaluate the usefulness of a source-attribution model in a country in which food animals are virtually free from Salmonella. The model allocates human sporadic domestic Salmonella cases to different sources according to distribution of Salmonella subtypes in the different sources. Sporadic domestic human Salmonella cases (n=1086) reported between July 2004 and June 2006 were attributed to nine food-animal and wildlife sources. Of all Salmonella cases, 82% were acquired abroad and 2·9% were associated with outbreaks. We estimated that 6·4% were associated with imported food, 0·5% with food-producing animals, and 0·6% with wildlife. Overall, 7·7% could not be attributed to any source. We concluded that domestic food-producing animals are not an important source for Salmonella in humans in Sweden, and that the adapted model is useful also in low-prevalence countries.

Towards an integrated approach in supporting microbiological food safety decisions.

Decisions on food safety involve consideration of a wide range of concerns including the public health impact of foodborne illness, the economic importance of the agricultural sector and the food industry, and the effectiveness and efficiency of interventions. To support such decisions, we propose an integrated scientific approach combining veterinary and medical epidemiology, risk assessment for the farm-to-fork food chain as well as agricultural and health economy. Scientific advice is relevant in all stages of the policy cycle: to assess the magnitude of the food safety problem, to define the priorities for action, to establish the causes for the problem, to choose between different control options, to define targets along the food chain and to measure success.

Survey of Campylobacter species, VTEC O157 and Salmonella species in Swedish wildlife.

Samples collected from 791 wild animals (Canada geese, roe deer, hares, moose, wild boar and gulls) shot during hunting were examined for verocytotoxin-producing Escherichia coli (VTEC) O157, and thermophilic Campylobacter and Salmonella species. With the exception of one positive isolate from a wild boar, VTEC O157 was not isolated from any of the animals. Salmonella species were isolated only from the gulls, of which 4 per cent were estimated to be positive. Thermophilic Campylobacter species were commonly isolated from all the species except deer.

Salmonella isolated from animals and feed production in Sweden between 1993 and 1997.

This paper presents Salmonella data from animals, feedstuffs and feed mills in Sweden between 1993 and 1997. During that period, 555 isolates were recorded from animals, representing 87 serotypes. Ofthose, 30 serotypes were found in animals in Sweden for the first time. The majority of all isolates from animals were S. Typhimurium (n = 91), followed by S. Dublin (n = 82). There were 115 isolates from cattle, 21 from broilers, 56 from layers and 18 from swine. The majority of these isolates were from outbreaks, although some were isolated at the surveillance at slaughterhouses. The number of isolates from the feed industry was similar to that of the previous 5-year period. Most of those findings were from dust and scrapings from feed mills, in accordance with the HACCP programme in the feed control programme. It can be concluded that the occurrence of Salmonella in animals and in the feed production in Sweden remained favourable during 1993-97.

Validation of a polymerase chain reaction/restriction enzyme analysis method for species identification of thermophilic campylobacters isolated from domestic and wild animals.

AIMS: To compare and evaluate a polymerase chain reaction/restriction enzyme analysis (PCR/REA) method with standard phenotypic tests for the identification and differentiation of the thermophilic campylobacters Campylobacter jejuni, C. coli, C. lari and C. upsaliensis. METHODS AND RESULTS: One hundred and eighty-two presumptive thermophilic campylobacters from 12 different animal species were tested by a recently published PCR/REA and standard phenotypic tests. By PCR/REA, 95% of the isolates were clearly identified as either one of the four thermophilic Campylobacter species or as not belonging to this group of organisms at all. By standard phenotyping, 174 of the 182 isolates were initially identified as either C. jejuni, C. coli, C. lari or C. upsaliensis. Additional genotypic tests and phenotyping showed that 52 of these identifications were either incorrect or unreliable. Of the C. jejuni isolates, 19% were identified as C. coli by initial phenotyping and 27 sheep isolates phenotyped as C. coli or C. lari were, in fact, arcobacters. CONCLUSIONS: The PCR/REA was more reliable than standard phenotyping for the identification of thermophilic campylobacters from different animals. SIGNIFICANCE AND IMPACT OF THE STUDY: Routinely used phenotypic tests often resulted in unreliable identifications, requiring additional testing. The PCR/REA, however, gave unequivocal results and was considered useful for the routine identification of thermophilic campylobacters from different animals.

Herd-based monitoring for tuberculosis in extensive swedish deer herds by culling and meat inspection rather than by intradermal tuberculin testing.

The effect of random slaughter and meat inspection as a tool to detect or eradicate tuberculosis in large, extensive deer herds in Sweden was evaluated. A computer spreadsheet model based on the Reed-Frost method was developed. Numbers of new infections and of infected deer slaughtered as well as probability of detecting tuberculosis or slaughtering all infected deer in a herd, were simulated. The model predicted that, given a 20% annual slaughter and that disease was introduced with one infected deer, the infection would be detected or eliminated in most herds (90%) after 15 years.

A Reed-Frost model of the spread of tuberculosis within seven Swedish extensive farmed fallow deer herds.

The within-herd transmission of tuberculosis, after introduction of infection, was evaluated in seven Swedish herds of farmed fallow deer. The evaluation was based on a subset of data obtained from a previous epidemiological investigation, comprising 13 tuberculosis-infected deer herds, with the purpose of tracing the source of infection. A computer spreadsheet model based on the Reed-Frost method was developed to estimate the number of new infections. For each herd, a k-value (the number of effective contacts made by an individual during a time period) was estimated through fitting the model to the observed incidence in each herd. We concluded that, despite the relatively short observation periods and uncertain tuberculosis incidence estimates for the observed herds, the k's obtained could be used to quantify the estimated spread of tuberculosis in extensive deer herds in Sweden.

[Policy program to minimize spread of infection. Prolonged cough may be a sign of tuberculosis]. / Policyprogram för minskad smittspridning. Långdragen hosta kan vara tuberkulos.

In a worldwide epidemiological perspective, Sweden is well favoured with an annual tuberculosis incidence of approximately six cases per 100,000 of the population. Neither the impact of the HIV pandemic nor the occurrence of multiresistant strains of Mycobacterium tuberculosis has yet become a major problem in the care of tuberculosis patients in Sweden. Only a few per cent of HIV patients have developed tuberculosis, and during the period, 1991-94, only one per cent of M. tuberculosis isolates in Sweden were resistant to such antimycobacterials as isoniazid and rifampicin. However, the epidemiological situation in the neighbouring Baltic states is a matter for concern. Bovine tuberculosis has been eradicated in Sweden, the last case having been diagnosed in 1978. Although the reported efficacy of BCG (bacillus Calmette-Guérin) tuberculosis vaccine varies according to the population studied, protective rates of 70-85 per cent have been reported for Sweden and other west European countries. Re-vaccination of tuberculin-negative individuals has not been shown to yield added protection. The aim of a national programme for protection against tuberculosis is to preserve our favourable epidemiological situation by early detection of new cases, effective contact tracing, and BCG vaccination of children in population groups at risk. The primary means of achieving this is the education of health care personnel to retain tuberculosis as a differential diagnosis. Moreover, national guidelines for contact tracing must be duly observed, and immigrants from high prevalence areas need to be screened for tuberculosis. Registration of all cases of tuberculosis should be maintained at regional and national levels, and follow-up must be meticulous until a successful outcome of treatment is accomplished. Recommendations for dealing with tuberculosis should be made available and duly implemented at all hospitals caring for tuberculosis patients, in order to avoid nosocomial transmission. Although BCG vaccination at birth was formerly general in Sweden, since 1975 only children considered to be at risk have been vaccinated. Thus, non-vaccinated young adults are now entering the health care sector as students or employees, and should be offered BCG vaccination. Moreover, the epidemiological situation both in Sweden and in neighbouring countries needs to be monitored carefully in order that recommendations concerning BCG vaccination and other preventive measures can be modified if necessary.

Comparison of loading capacities of various proteins and peptides in culture medium and in pure state.

Chromatographic media suppliers most frequently state the capacities of their gels based on either static capacities or frontal analysis experiments of pure proteins, however, these capacity values are often far from the capacities experienced in the production of such proteins. In this work static and dynamic capacities of various pure industrial proteins or peptides are compared to the capacities of the proteins or peptides under similar conditions in their natural culture medium. The results show a significant decrease in the static and dynamic capacities of the proteins or peptides when present in culture medium due to competitive binding of medium proteins. The proteins and peptides included in this study are: lipolase, glucagon-like peptide-1, truncated prothrombin, insulin precursor, and anti-Factor VII monoclonal antibody.

Aureobasidium pneumonia in a post liver transplant recipient: a case report.

This is the first report of Aureobasidium (A.) pullulans as an opportunistic pulmonary infection in a liver transplant recipient. A 46-year-old caucasian man had an orthotopic liver transplant in 1988. His liver disease was primary sclerosing cholangitis. He required 2 subsequent liver re-transplants for primary graft non-function and acute rejection. The patient had been living in the California desert for two months prior to admission and presented with ventilator-dependent acute respiratory failure and hemodialysis-dependent acute renal failure. Imaging studies revealed severe bilateral infiltrates. His initial bronchoalveolar lavage (BAL) and brushings grew A. pullulans. Pancultures, including sputum and throat cultures, were negative for bacterial or other fungal organisms. The patient responded to pulmonary support and aggressive systemic antifungal agents while being maintained on cyclosporine and prednisone for immunosuppression. He was discharged to a skilled nursing facility 37 days after hospitalisation. Delay in discharge was primarily due to severe malnutrition and renal impairment. Opportunistic fungal infections continue to be a major problem in immunosuppressed patients including liver transplant recipients. Here we report a pulmonary infection with Coccidioides (C.) immitis and superinfection with A. pullulans. Opportunistic infections such as A. pullulans can be treated successfully with systemic fluconazole when amphotericin B is not well tolerated.

A chiral capillary electrophoresis method for ropivacaine hydrochloride in pharmaceutical formulations: validation and comparison with chiral liquid chromatography.

A capillary electrophoresis method for the determination of the enantiomeric purity of the local anaesthetic ropivacaine hydrochloride in injection solutions has been validated. The method showed the required limit of quantitation of 0.1% enantiomeric impurity. Good performances were shown for specificity, linearity, system repeatability, intermediate precision and accuracy. Robustness was tested via a full factorial design at two levels and the method proved to be robust. Comparison of the capillary electrophoresis method with the liquid chromatographic method currently used for several years at our laboratory on real samples of ropivacaine injection solutions showed that the techniques do not give significantly different results.

Conventional care of fulminant hepatic failure: medical and surgical aspects.

Fulminant hepatic failure (FHF) is a clinical syndrome with a poor outcome. Survival rates are between 10% and 40% depending on the etiology of hepatic necrosis. Multiple supportive modalities have been tried to improve patient outcome. However, orthotopic liver transplantation has been shown to be the most effective therapy at improving survival. Management of these patients requires invasive monitoring, mechanical ventilation, and infection prophylaxis, all of which are conducted most efficiently in specialized units. The goal is to allow the native liver to regenerate and to prevent the development of complications while maintaining the patient in a condition suitable for orthotopic liver transplantation. Therapeutic plasma exchange improves survival in patients with sufficient residual capacity for regeneration. It is effective in restoring hemostasis, improving neurological function, and prolonging biochemical stability of patients awaiting liver transplantation. Hepatoprotective and hepatotrophic substances are still in the experimental stage. Auxiliary liver grafting and artificial liver support devices have proved to be an adjunct or a bridge to transplantation; however, they are not yet widely available.

Characteristics of the glomerular capillary membrane of the rat kidney as a hydrated gel. I. Hypothetical structure.

It is suggested that the glomerular capillary membrane constitutes a flexible gel, where negative charges fixed to the matrix of the membrane account for the maintenance of its integrity. In this model, the hydrostatic pressure throughout the membrane is assumed to equal the glomerular capillary pressure. Pglom. of 56.7 mmHg. On the plasma side of the membrane, the charge-induced electro-osmotic pressure therefore has to balance the colloid osmotic pressure of glomerular plasma, and on its Bowman's space side, it has to balance the pressure drop. Pglom-PBow, across this interphase. Using micropuncture technique, the glomerular plasma colloid osmotic pressure of 20.6 mmHg was found to require a charge density of 24.8 mEq L-1 and the pressure drop at the Bowman's space side of 56.7-12.2 = 44.5 mmHg a density of 36.6 mEq L-1. The transmembranous electric potential difference was estimated at -1.1 mV. a potential which, in a negatively charge membrane, will also constitute the net driving force for the fluid transfer; this force will be close to, but not identical with, that calculated as conventional from the Starling forces of, in the present case, 23.9 mmHg.61 In the present analysis the distribution of charges in the fluid of the pore resulting from charged groups fixed to the rim of the pore is also considered.

Characteristics of the glomerular capillary membrane of the rat kidney as a hydrated gel. II. On the validity of the model.

In our gel model applied to the glomerulus, maintenance of membrane integrity is assumed to be preserved not by rigid elements but by the electro-osmotic and balancing hydrostatic pressure offered by negative, fixed charges such that the membrane is able to withstand the external colloid osmotic and hydrostatic forces. Ir a previous study we used micropuncture data to estimate the charge densities required to fulfil this assumption. In the present study the validity of the model was examined from the transport of neutral and negative charged myoglobin as derived from their concentrations in renal venous blood. In order to determine the size of the pores, or rather meshes in the network, the venous concentration of [51Cr]EDTA was also analysed. Based on the ratio between EDTA and neutral myoglobin of 1.08 +/- 0.010 (mean +/- SE, n = 9), the equivalent pore radius was calculated to be approximately 40 A. The ratio of neutral to negative myoglobin in the two series performed was found to be 0.96 +/- 0.018 (n = 8) and 0.97 +/- 0.05 (n = 7), figures which were the same as ratio of 0.97 predicted on theoretical grounds. It is concluded that the experimental data support the hypotheses, although they may also be adapted to the transport in a homogeneously charged membrane; the charge density in this case was estimated at 2.3 mEq L-1. Assuming that the membrane constitutes a network with quadratic meshes, each fibre would seem to carry binding sites approximately 80 A apart and where, in between these binding sites, each fibre was calculated to carry three charges such that the mesh will thus be surrounded by 12 charges.

Molecular epidemiological studies of Mycobacterium bovis infections in humans and animals in Sweden.

Forty-nine isolates of Mycobacterium bovis from humans and animals in Sweden were analyzed by restriction fragment length polymorphism (RFLP) patterns probed by the insertion element IS6110. Most isolates had patterns indicating the presence of only one or two genomic copies of the IS6110 insertion element. This simple type of pattern was found in all human isolates. In contrast, isolates from M. bovis infections in five herds of farmed deer in Sweden showed a specific RFLP pattern with seven bands, indicating seven copies of the IS6110 sequence. In 1958, Sweden was declared free from M. bovis in cattle. However, in 1987, M. bovis was reintroduced with imported farmed deer, and since 1991, 11 outbreaks in deer herds, but not in other livestock or wildlife, have been diagnosed. Continued RFLP studies of the new Swedish M. bovis isolates can reveal possible transmission of this deer strain to other animals or humans.