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Unlabelled: Salmonella groups of organisms are recognized as predominant in food poisoning outbreaks, but knowledge of the primary source of Salmonella bacilli and of paths of infection to implicated food is incomplete.-Unsolved problems discussed.-Food animals suffering from Salmonella infection are common in Germany but comparatively rare in this country and in most outbreaks the original food is shown to have been sound.-Infection of food from a human carrier is extremely rare. Detailed study of individual outbreaks brings out the striking fact that the Salmonella strains which cause food poisoning are just those types capable of causing disease in both man and animals. The hypothesis which best explains bacterial causation of most outbreaks is that the source of infection is derived, in most cases, from animals suffering from Salmonella disease or acting as carriers of these bacilli. Many facts favour this view, including the widespread extent of Salmonella infections in animals associated with food., Examples: Cows suffering from Salmonella infections with these bacilli in the milk; the widespread prevalence of such infections in rats and mice; the considerable extent to which pigs are infected with Salmonella bacilli.-Attention is directed to the presence of specific agglutinins in the blood of food animals such as bullocks and pigs, also to the fact that while in man a carrier condition for food-poisoning bacilli is extremely rare and at best a transient condition in animals. It is a well attested phenomenon. The causes of this difference are worthy of further study.Not only are there numerous types within the Salmonella group but these types exhibit characteristic and definite differences of pathological behaviour. Bacillus paratyphosus B and Bacillus aertrycke furnish a good illustration and these two types are critically contrasted.While our present knowledge is imperfect, it is suggested that the types in this group fall into three groups, i.e., (a) Strains pathogenic to man but not to animals; (b) strains pathogenic to animals but harmless to man; (c) strains pathogenic both to man and to animals. Only the last group cause food-poisoning outbreaks and represent the original and less specialized types.Varying virulence of Salmonella strains and problems thus raised in relation to food poisoning outbreak are discussed.

Elevated concentrations of the fecal indicator bacteria (FIB) Escherichia coli and enterococci in recreation and irrigation waters indicate a human health risk. Little is known about the role of sandy bottom sediments as a factor for the microbial quality of water. The objective of this work was to compare the dynamics of FIB concentrations and total numbers in water columns and sandy sediments along a 30-km reach of the Conococheague Creek in Southern Pennsylvania. Sampling locations were located near forested headwater subwatershed outlet, in the mixed agricultural use area, and in the mixed urban-agricultural land use area. Water and sediment samples were taken weekly for 3 years. Concentrations of both FIB followed similar persistent intra-annual sine-like annual trends with amplitudes of 3 to 3.5 orders of magnitude in the water column and sediment. Concentrations generally increased from the forested site to the mixed urban-agricultural site. Pearson correlation coefficients between logarithms of concentrations in water and in sediment were between 0.622 and 0.756 for E. coli and between 0.320 and 0. 621 for enterococci. FIB areal densities were computed as total CFU per unit area for water columns and for 1-cm top sediment. The ratios of E. coli CFU areal densities in water and sediment increased with the stage by 4 to 12% per 1 cm increase of the stream stage. Such a trend was also seen for enterococci at the forested site. Overall, populations of both FIB were substantially larger in water than in sediment at agricultural and mixed sites, urban-agricultural development sites. In such conditions, a first approximation of monitoring and modeling microbial water quality results can apparently be obtained without including the sediment compartment in observations and computations. [ABSTRACT FROM AUTHOR]

Hot cracking susceptibility and the formation of brittle martensite phase are the main factors that limit the weldability of a dissimilar joint between carbon steel (CS) and austenitic stainless steel (SS). In this study, the self-constraint finger test was used to correlate the welding thermo-mechanical field with the crack susceptibility of a dissimilar weld between the CS ASTM A36 and SS AISI 304L. The finger test allowed to intercalate fingers (portions) of tested materials in the weld samples to produce dissimilar welds. The heat dissipation and the distortion behavior were related to the crack susceptibility, critical weld regions extension, and chemical species diffusion. Four samples were welded (two similar welds and two dissimilar welds) using the filler metals ER70S-6 and EC410NiMo. Welds were analyzed through light optical microscopy (LOM) and scanning electron microscopy (SEM) to characterize phases, detect cracks, microstructural changes, and element diffusion. A finite element (FE) numerical model was applied to simulate the welding thermo-mechanical field. FE estimations of distortion and residual stress helped to predict induced crack propagation (the initial gap between fingers) towards the fusion zone. Additionally, electrochemical tests were carried out to assess the corrosion susceptibility of the dissimilar welds. The observed cracks were produced due to different factors such as residual stress distribution, the formation of brittle and untempered martensitic phase in the fusion zone (FZ), and hot cracking associated with the weld sample distortion behavior. According to the FE estimations, the high thermal expansion of the SS was responsible for the bending curvature change in welds 2 and 4, which produced a gap between fingers and increased the crack extension in the FZ of weld 4. The dilution contributed to the formation of δ-ferrite in the FZ, which limited the growth of cold and hot cracks. The decarburization and sensitization were not observed in dissimilar welds due to the low element diffusion. [ABSTRACT FROM AUTHOR]

Coastal water quality in urban cities is increasingly impacted by human activities such as agricultural runoff, sewage discharges, and poor sanitation. However, environmental factors controlling bacteria abundance remain poorly understood. The study employed multiple indicators to assess ten beach water qualities in Ghana during minor wet seasons. Environmental parameters (e.g. temperature, electrical conductivity, total dissolved solids) were measured in situ using the Horiba multiple parameter probe. Surface water samples were collected to measure total suspended solids, nutrients, and chlorophyll-a via standard methods and bacteria determination through membrane filtration. Environmental parameters measured showed no significant variation for the sample period. However, bacteria loads differ significantly (p = 0.024) among the beaches and influenced significantly by nitrate (55.3%, p = 0.02) and total dissolved solids (17.1%, p = 0.017). The baseline study detected an increased amount of total coliforms and faecal indicator bacteria (Escherichia coli and Enterococcus spp.) in beach waters along the coast of Ghana, suggesting faecal contamination, which can pose health risks. The mean ± standard deviations of bacteria loads in beach water are total coliforms (4.06 × 103 ± 4.16 × 103 CFU/100 mL), E. coli (7.06 × 102 ± 1.72 × 103 CFU/100 mL), and Enterococcus spp. (6.15 × 102 ± 1.75 × 103 CFU/100 mL). Evidence of pollution calls for public awareness to prevent ecological and health-related risks and policy reforms to control coastal water pollution. Future research should focus on identifying the sources of contamination in the tropical Atlantic region. [ABSTRACT FROM AUTHOR]

The European badger (Meles meles) has been identified as a wildlife reservoir of bovine tuberculosis and a source of transmission to cattle in Britain and Ireland. Both behavioural ecology and statistical ecological modelling have indicated the long-term persistence of the disease in some badger communities, and this is postulated to account for the high incidence of bovine tuberculosis in cattle across large tracts of England and Wales. This paper questions this consensus by using historical cartographic evidence to show that tuberculosis in cattle had a very different spatial distribution before 1960 to the present day. Since few of the badgers collected in road traffic accidents between 1972 and 1990 had tuberculosis in counties such as Cheshire, where the disease had until shortly before that been rife in the cattle population, the role of badgers as reservoirs in spreading disease in similar counties outside the south-west of England has to be questioned. [ABSTRACT FROM AUTHOR]

Background: Susceptibility to disease after infection by Mycobacterium tuberculosis is influenced by environmental and host genetic factors. Vitamin D metabolism leads to activation of macrophages and restricts the intracellular growth of M tuberculosis. This effect may be influenced by polymorphisms at three sites in the vitamin D receptor (VDR) gene. We investigated the interaction between serum vitamin D (25-hydroxycholecalciferol) concentrations and VDR genotype on susceptibility to tuberculosis. Methods: This study was a hospital-based case-control analysis of Asians of Gujarati origin, a mainly vegetarian immigrant population with a high rate of tuberculosis. We typed three VDR polymorphisms (defined by the presence of restriction endonuclease sites for Taq1, Bsm1, and Fok1) in 91 of 126 untreated patients with tuberculosis and 116 healthy contacts who had been sensitised to tuberculosis. Serum 25-hydroxycholecalciferol was recorded in 42 contacts and 103 patients. Findings: 25-hydroxycholecalciferol deficiency was associated with active tuberculosis (odds ratio 2.9 [95% Cl 1.3-6.5], p=0.008), and undetectable serum 25-hydroxycholecalciferol (<7 nmol/l) carried a higher risk of tuberculosis (9.9 [1.3-76.2], p-0.009). Although there was no significant independent association between VDR genotype and tuberculosis, the combination of genotype TT/Tt and 25-hydroxycholecalciferol deficiency was associated with disease (2.8 [1.2-6.5]) and the presence of genotype if or undetectable serum 25-hydroxycholecalciferol was strongly associated with disease (5. 1 [1.4-1 8. 4]). Interpretation: 25-hydroxycholecalciferol deficiency may contribute to the high occurrence of tuberculosis in this population. Polymorphisms in the VDR gene also con- tribute to susceptibility when considered in combination with 25-hydroxycholecalciferol deficiency. [ABSTRACT FROM AUTHOR]

Focuses on the role of leukocytes in the immunopathogenesis of antineutrophil cytoplasmic autoantibody (ANSA)-associated glomerulonephritis. Effectiveness of cyclophosphamide-based treatment regimens in ANSA-associated necrotizing glomerulonephritis (GN); Histological characteristics of ANSA-associated GN; Four distinct stages through which GN of ANCA-associated vasculitis progresses.

The article presents abstracts from the 38th Annual Scientific Meeting of the Australian & New Zealand Division, which took place from September 27-29, 1998 and discussed several topics including tooth wear, the rate of wear with dental glass ionomer cements and composite resins, and the proportional microdontia of permanent teeth among individuals with Down syndrome. A list of participants is also provided.

Summary The National Health Service Act 1946 transferred responsibility for the non-voluntary hospitals and certain clinical services from the public health departments of counties and county boroughs to new regional hospital boards, thereby substantially reducing the functions of their medical officers of health and creating a separate cadre of doctors concerned with the planning and management of hospital and specialist services. At around the same time there was pressure to develop in each medical school a department of social and preventive medicine with fulltime staff involved in research work. Reviewing the situation 20 years later, the Royal Commission on Medical Education recommended that doctors in public health, medical administration or related teaching and research should form a single professional body concerned with the assessment of specialist training for and standards of practice in 'community medicine'. Immediately after the publication of the Commission's Report in 1968, J. N. Morris invited leaders in the three strands of activities to meet and discuss the proposal. A series of informal meetings led to the setting up, in 1969, of a Working Party (chairman, J. N. Morris) which negotiated with the Royal Colleges of Physicians of Edinburgh, Glasgow and London for them to create a faculty of community medicine. In November 1970 the Colleges set up a Provisional Council (chairman, W. G. Harding), later Board, and the Faculty formally came into existence on 15 March 1972. The key decisions and some of the complications and hitches encountered in achieving this radical outcome are described in this paper. [ABSTRACT FROM PUBLISHER]

Background Although the incidence of bovine tuberculosis in UK cattle has declined markedly, outbreaks still occur. There is often confusion as to how veterinary and human public health agencies should interact in such circumstances. We report an outbreak of bovine tuberculosis which occurred in South West Scotland in 1992. Methods The outbreak, which affected two cattle herds, and potentially involved 17 humans, was discovered when visible tuberculous lesions were found at routine post mortem examination of a calf. Investigation of animals and humans, exchange of information between human and veterinary public health agencies, and subsequent control measures followed the guidance of a recently produced protocol. Results Tuberculin testing of other animals in the index herd revealed 11 reactors. Testing of the herd of origin of these animals revealed 84 reactors out of 261 animals. Movement restrictions were placed on the index herd, and all the animals in the herd of origin were slaughtered. The humans were screened primarily by history and tuberculin skin testing. Eleven of them required chest X-rays (all were normal) and six were given prophylactic chemotherapy with isoniazid. Nobody developed clinical illness. Conclusion The use of an agreed protocol proved to be very helpful to both human and veterinary public health agencies in the investigation and control of an outbreak of bovine tuberculosis. There is a clear need for better human screening tests. [ABSTRACT FROM PUBLISHER]

This article focuses on the transmission of infectious disease mycobacterioses by accidental inoculation. Mycobacterioses of man consist of four named diseases such as tuberculosis, leprosy, Buruli ulcer and swimming pool granuloma and a number of tuberculosis like infections of protean manifestations caused by environmental mycobacteria. Notably, three of the four named diseases predominantly affect the skin, and cutaneous manifestations of tuberculosis. Nor all dermal mycobacterial infections result from direct implantation of the causative organisms into the skin although this is an important and often preventable mode of infection.

The article presents a discussion paper on the dogma and innovation in the global control of tuberculosis. Tuberculosis has been a major concern for health care providers and many researches have been initiated and directed towards it. There should be collaboration between the advocates of the forms of therapy to develop combined approaches in controlling tuberculosis. An urgency for easily supervisable therapy supplemented by immunotherapy and other approaches are needed.

Editorial. Focuses on developments in efforts to find an effective vaccine for tuberculosis. Results of clinical trials to determine the safety and efficacy of the BCG vaccine; Opportunities for vaccine development arising from the characterization of the entire genome of the Mycobacterium tuberculosis.