bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid and automated detection of salmonella by electrical measurements
Authors: Easter M. C. , Gibson D. M.
Published: October 2009

A rapid method for determining the presence of salmonella in food is described. It consists of pre-enrichment in buffered peptone water modified by the addition of dulcitol. and trimethylamine oxide, followed by selective enrichment in a selenite—cystine broth with similar modifications. Changes in the conductance of the selective enrichment broth are monitored continuously using a suitable impediometric instrument. Most of theSalmonellaspp. tested gave a fast (˜100 μS/h) and large (> 600 μS) change in conductance, other enteric bacteria much less or no change. The assay is usually complete within 24 h. Samples of foodstuffs, naturally and artificially contaminated withSalmonellaspp., were all correctly classified. Some strains ofCitrobacter freundiiproduced a false positive conductance response, and they could not be selectively eliminated using antibiotics or cyanide. The conductance method is simple and easy to use, gives rapid results and involves less media and subculturing than is required for traditional methods.
A study of enterotoxigenicEscherichia coli, serogroup 0126, by bacterial restriction endonuclease DNA analysis (BRENDA)
Authors: Marshall R. B. , Winter P. J. , Robinson A. J. , Bettelheim K. A.
Published: October 2009

Sixteen isolates ofEscherichia coliwere subjected to bacterial restriction endonuclease DNA analysis (BRENDA). Nine of these isolates were from an outbreak of human diarrhoea and produced stable toxin, the remaining seven were non-toxigenic strains from animal and human sources. The isolates from the outbreak produced indistinguishable DNA electrophoretic patterns in spite of their assignment to seven different H serotypes. Their BRENDA patterns were markedly different from the other isolates examined. These results support the epidemiological evidence that a single-strain outbreak had occurred, and they cast doubt on the value of H typing for this particular investigation.
Evaluation of coumatetralyl against two predominant murid species
Authors: Chopra Girish , Parshad V. R.
Published: October 2009

Coumatetralyl was evaluated in the laboratory against Bandicota bengalensis and Rattus rattus. Feeding tests with 0·0375 % coumatetralyl baits produced 100 % mortality after a single day feeding period in B. bengalensis and after a 10–day period in R. rattus. The anticoagulant bait is less palatable in comparison to plain bait. In the case of R. rattus, LFP50 and LFP98 and their 95 % confidence limits were 3·89 (2·62–5·77) days and 11·22 (6·1–20·65) days respectively. Median period of survival and its 95% confidence limits of B. bengalensis and R. rattus were 4·7 (3·85–5·7) days and 11·2 (9·33–13·44) days respectively.
Age-related changes in the rate of disease transmission: implications for the design of vaccination programmes
Authors: Anderson R. M. , May R. M.
Published: October 2009

Mathematical models are developed to aid in the investigation of the implications of heterogeneity in contact with infection within a community, on the design of mass vaccination programmes for the control of childhood viral and bacterial infections in developed countries. Analyses are focused on age-dependency in the rate at which individuals acquire infection, the question of ‘who acquires infection from whom’, and the implications of genetic variability in susceptibility to infection. Throughout, theoretical predictions are based on parameter estimates obtained from epidemiological studies and are compared with observed temporal trends in disease incidence and age-stratified serological profiles.

Analysis of case notification records and serological data suggest that the rate at which individuals acquire many common infections changes from medium to high and then to low levels in the infant, child and teenage plus adult age groups respectively. Such apparent age-dependency in attack rate acts to reduce slightly the predicted levels of herd immunity required for the eradication of infections such as measles, when compared with the predictions of models based on age-independent transmission. The action of maternally derived immunity in prohibiting vaccination in infants, and the broad span of age classes over which vaccination currently takes place in the U.K., however, argue that levels of herd immunity of between 90 and 94 % would be required to eliminate measles.

Problems surrounding the interpretation of apparent age-related trends in the acquisition of infection and their relevance to the design of vaccination programmes, are discussed in relation to the possible role of genetically based variation in susceptibility to infection and observations on epidemics in “virgin” populations. Heterogeneous mixing models provide predictions of changes in serology and disease incidence under the impact of mass vaccination which well mirror observed trends in England and Wales.
Biotypes and serotypes of thermophilic campylobacters isolated from cattle, sheep and pig offal and other red meats
Authors: Bolton F. J. , Dawkins H. C. , Hutchinson D. N.
Published: October 2009

In this study we examined 730 faecal samples of offal (mainly liver), mince-meat and sausage meat collected from abattoirs and retail butchers' shops for campylobacters.Campylobacter jejuniorC. coliwere isolated from 30·6, 10·5 and 6% of sheep, cattle and pig offal samples respectively. Specimens collected from abattoirs were, in general, more often contaminated than material obtained from retail butchers' shops. Only 1·4% of minced meats and sausage meats contained campylobacters. Most isolates (89·5%) wereC. jejunibiotype 1 (Skirrow & Benjamin, 1980) of serotypes 1 and 2 (Penner & Hennessy, 1980). This study shows that animal offal is frequently contaminated withC. jejuniof biotypes and scrotypes commonly isolated from human beings with campylobacter enteritis.
A comparison of virulence of two strains ofLegionella pneumophilabased on experimental aerosol infection of guinea-pigs
Authors: Jepras R. I. , Fitzgeorge R. B. , Baskerville A.
Published: October 2009

Two strains ofLegionella pneumophila(LP) serogroup I, of differing virulence, were examined in terms of numbers of viable organisms in tissues, pyrexia and mortality following aerosol infection. The Corby strain was the more virulent, with Pyrexia and deaths of guinea-pigs 3 to 6 days after infection. This strain multiplied very rapidly in the lungs to reach a peak of 5 × 1011viable organisms/lung. Organisms were present in the blood, liver, spleen and kidney. The Philadelphia-1 strain (NCTC 11192) was unable to replicate in the lung and was cleared between 14 and 21 days after infection. Pyrexia was not observed. No guinea-pigs died and viable LP was not found in any organ other than the lung.

Lung lavages on aerosol infected animals were performed and the virulent Corby strain was found to be mainly intracellular. The avirulent Philadelphia-1 strain was found predominantly in the extracellular location. There were approximately 10 times the number of viable virulent LP in the lung macrophage fraction than in the lung PMNL fraction. In comparison, there were approximately equal numbers of the viable avirulent strain in the macrophages and the PMNL. Experimental evidence suggests that the macrophage preferentially supports the growth of the virulent Corby strain compared with the PMNL. The avirulent strain on the other hand appears to be destroyed by both the macrophages and the PMNL.
The weak immunogenicity of Fusobacterium necrophorum
Authors: Smith G. R. , Turner Ann , Murray L. G. , Oliphant Janet C.
Published: October 2009

Three of four extreme methods of immunization completely failed to protect mice against challenge with the homologous strain of Fusobacterium necrophorum. Unsuccessful vaccines included (1) broth culture killed by mild heat and emulsified with Freund's complete adjuvant, and (2) a homogenate of heavily infected mouse brains, inactivated by mild heat and given in two doses. Also unsuccessful as a method of immunization was the production of a severe subcutaneous infection with F. necrophorum, followed by curative treatment with metronidazole. Slight but significant protection against subcutaneous challenge resulted, however, from two such infections given in rapid succession. It would appear that the main virulence factors of F. necrophorum are onty weakty immunogenic, and the experiments give little encouragement to the prospect of an effective necrobacillosis vaccine.
The effects of oxytetracycline on the intestinalEscherichia coliflora of newly weaned pigs
Authors: Hinton M. , Hampson D. J. , Hampson Elisabeth , Linton A. H.
Published: October 2009

Four recently weaned pigs were dosed orally with oxytetracycline. This caused a rapid increase in the incidence of tetracycline resistance (TcR) amongEscherichia coliisolates from the faecal flora. The isolates were differentiated further on the basis of O-serogroup, biotype and resistance pattern. There was no evidence that the administration of the antibiotic selected for a few TcR clones, but rather a relatively large number of TcR strains were identified during the dosing period. Using selective isolation media a proportion of these strains were demonstrated in the minority faecalEsch. coliflora before dosing, while the remainder were recognized for the first time after dosing commenced.

The incidence of TcR amongEsch. coliisolates also increased after weaning in other pigs which were not dosed with oxytetracycline or any other antibacterial agent. In a proportion of these animals this increase was associated with the dominance of a TcR enteropathogenic serotype (0149:K 91, K 88a, c) in the faecalEsch. coliflora which was probably ingested in small numbers before weaning. The source of other TcR strains was probably the environment in which each pig was placed after weaning.
Utilization ofd-tartaric acid bySalmonella paratyphi BandSalmonella java: comparison of anaerobic plate test, lead acetate test and turbidity test
Authors: Barker Ruth M.
Published: October 2009

d-Tartrate dehydrase ofSalmonella javais an oxygen-sensitive enzyme active in cultures incubated under the poorly aerated conditions of static culture but not in fully aerated shaken cultures nor on plates incubated aerobically. On plates ofd-tartrate minimal agar incubated anaerobically the enzyme or the degradation products ofd-tartrate are exported fromd-tartrate-positive cells and are available tod-tartrate-negative bacteria. This may give misleading growth results whend-tartrate-positive andd-tartrate-negative strains are tested for growth on the same plate ofd-tartrate minimal agar.

The lead-acetate test terminated at 24 h, the 24 h turbidity test and the ability to grow ond-tartrate minimal agar within 48 h differentiated 53S. paratyphi Bstrains that were negative in each of the three tests from 76S. javathat were positive in each of the tests. An intermediate group of eight strains utilizedd-tartrate in Difco bacto-peptone water to give a positive lead acetate reaction at 2 days, were stimulated to a varying degree byd-tartrate in Oxoid peptone water within the same period of incubation and grew poorly ond-tartrate minimal agar. These latter strains may be deficient in a permease controlling uptake ofd-tartrate or export ofd-tartrato dehydrase.

Inability to utilized-tartrate is unlikely to be the single character accountable for the reputed enhanced pathogenicity ofS. paraptyphi Bwhen compared withS. java.Indications for the existence of an enzyme, complementary to and mutually exclusive withd-tartrate dehydrase, that has a positive correlation with pathogenicity are discussed.
The effect of surgical gowns made with barrier cloth on bacterial dispersal
Authors: Matthews Julie , Slater K. , Newsom S. W. B.
Published: October 2009

A dispersal chamber (body box) technique has been used to compare bacterial dispersal from the skin of subjects carrying out a stepping test under controlled conditions while wearing four differing garment systems namely:

(a) basic underwear, cotton ‘blues’ (standard pyjama style jacket and trousers for men or dress for women), ankle socks, boots for men and shoes for women, mask and theatre hat; (b) the basic set covered with a cotton gown; (c) the basic set covered by a gown with a front made from GORE-TEX fabric in which an expanded polytetrafluoroethylene membrane is sandwiched between layers of woven or knitted polyester; (d) the basic set covered with a fully enclosed suit of the same fabric.

A slit sampler was used to measure the number of bacteria liberated in a downward current of air. Six subjects (three female and three male) were studied. Males liberated more bacteria. Covering the ‘blues’ with a cotton gown increased the bacterial count; a gown of the new material reduced the increase by 50%, and the suit cut the dispersal to virtually zero.

Preliminary work suggests that GORE-TEX garments survive laundering better than cotton, and may be cost-effective, but are not yet as comfortable. Research is presently in progress to improve this aspect.
Salmonella isolation with Rappaport–Vassiliadis enrichment medium seeded with different sized inocula of pre-enrichment cultures of meat products and sewage polluted water
Authors: Vassiliadis P. , Mavrommati Ch. , Kalapothaki V. , Chronas G. , Efstratiou M.
Published: October 2009

A total of 574 samples, of seven different types, were examined for the presence of salmonellas. All the specimens were pre-enriched in buffered peptone water and enriched in Rappaport–Vassiliadis medium (RV medium). In one trial 0·1 ml of pre-enrichment culture of 497 samples (79 chicken carcasses, 228 specimens of minced meat, 100 pork sausages, 19 samples of dried powdered chicken meat, 11 specimens of faeces of healthy pigs and 60 samples of sewage polluted natural sea water) was seeded to 10 ml as well as to 100 ml of RV medium. With the first inoculum (ratio 0·1:10), 111 samples were found to contain salmonellas, while with the second inoculum (ratio 0·1:100), only 102 positive samples were detected. This difference is marginally significant (P < 0·05). In another trial, 0·1 ml, 0·2 ml and 0·5 ml of pre-enrichment culture of 162 specimens (71 chicken carcasses, 40 samples of sewage polluted sea water and 51 samples of sewage polluted river water) were in turn introduced to 10 ml of RV medium. With the 0·1 ml inoculum 93 positive samples were detected, while with the 0·2 and 0·5 ml inocula 93 and 88 positive samples were found. The differences are not statistically significant. In these trials the growth of competing organisms was minimal with ratios of inocula 0·1:10 or 0·1:100.
A study of the host range and distribution of antibody to Akabane virus (genus bunyavirus, family Bunyaviridae) in Kenya
Authors: Davies F. Glyn , Jessett D. M.
Published: October 2009

Serum neutralizing antibody to Akabane virus (genus bunyavirus, family Bunyaviridae) was found in a high proportion (50–95%) of cattle sampled in Kenya, while sheep and goats had fewer positive (13–33%). Camel and horse sera also contained antibody to the virus (70% and 50% respectively). The antibody was found in animals from the high altitude temperate type of grasslands, drier bushed and wooded grasslands and the semi-desert. No arthrogryposisnor hydranencephaly has been encountered in Kenya which might be related to this widespread virus infection.

A wide range of Kenyan wild ruminants had antibody to Akabane virus in their sera, as also did zebra.
Clostridium difficilein general practice and community health
Authors: Riley T. V. , Wymer Valerie , Bamford V. W. , Bowman R. A.
Published: October 2009

The isolation rate forClostridium difficilein diarrhoeal stools was investigated in patients from general practice and community health centres over a 14-month period.C. difficileor its cytotoxin was detected in specimens from 89 (4·7 %) of 1882 patients studied and accounted for 30·3 % of all enteropathogenic micro-organisms isolated. OverallC. difficilewas second only toGiandia lambliain frequency. Recovery rates in the different groups of patients surveyed varied from 3·6 to 27·5 %. The relationship between stool culture results and stool cytotoxin assay also varied considerably between groups of patients studied. Coincident infections with a variety of enteropathogenic bacteria and intestinal parasites were diagnosed in 14 of the 89 patients. It was concluded that laboratories servicing this type of practice should be aware thatC. difficilemay be a cause of diarrhoea. An adequate clinical history should facilitate proper processing of the specimen.
Microbiological quality of desiccated coconut
Authors: Kinderlerer Judith L. , Clark Rachel A.
Published: October 2009

A microbial survey of Sri Lankan desiccated coconut has been made on material purchased in supermarkets in Sheffield or on material obtained directly from the processing company. The total viable count (TVC) was reduced by spoilage and pasteurization from 104/g to 103/g. Most samples contained low levels of coagulase-positiveStephylococcus aureussuggesting that this commodity had been handled during production. One focus of contamination withAspergillus flavuswas found for each 8·34 g of desiccated coconut (mean contamination). The number of bacteria and moulds in spoiled coconut was significantly lower than that in coconut obtained from the processor or purchased from retail outlets. It is suggested that the accumulation of free fatty acids, aliphatic methyl ketones and secondary alcohols produced during fungal spoilage has had a bactericidal and fungicidal effect. The use of microbial specifications for foods is questioned in situations where there is evidence of microbial spoilage having taken place.
The relationship between the serogroup antigen and lipopolysaccharide ofLegionella pneumophila
Authors: Conlan J. W. , Ashworth L. A. E.
Published: October 2009

Serogroup-specific antigen was extracted from a number ofLegionella pneumophilastrains and compared with phenol-water extracted lipopolysaccharide on the basis of gel filtration, chemical analysis, SDS-PAGE and reaction with serogroup-specific antibody in immunoblots. Serogroup specificity is apparently borne by the O side-chains of the lipopolysaccharide, which, although smooth in type, partitions in the phenol phase. For four serogroup 1 strains tested, there was no qualitative correlation between O side-chain length and pulmonary virulence for guinea-pigs.
International outbreak of staphylococcal food poisoning caused by contaminated lasagne
Authors: Woolaway M. C. , Bartlett C. L. R. , Wieneke Antonnette A. , Gilbert R. J. , Murrell Helen C. , Aureli P.
Published: October 2009

An outbreak of staphylococcal food poisoning in Europe caused by contaminated lasagne was detected and monitored by both national and international surveillance systems. The common source was a pasta-producing factory in Italy and high levels of Staphylococcus aureus were detected in packets of dried lasagne distributed in Luxembourg, the UK, France and Italy. Forty-seven cases were reported in the UK. Outbreaks of staphylococcal food poisoning attributed to mishandling during the food processing stage are uncommon and pasta as the food vehicle is rare. Prompt recognition of the outbreak and rapid identification of the food vehicle enabled most of the consignment to be withdrawn from the market.
Cryptosporidium plus campylobacter: an outbreak in a semi-rural population
Authors: Casemore D. P. , Jessop E. G. , Douce D. , Jackson F. B.
Published: October 2009

An outbreak of cryptosporidiosis in a circumscribed semi-rural population is described; some cases were infected concurrently with campylobacter. The results of a detailed case-control study and environmental surveillance are discussed.
Further investigations of a hydatid focus in North-West Scotland
Authors: Moir Isobel L. , Chrystall Caroline J. , Joss A. W. L. , Williams H.
Published: October 2009

A serological survey carried out on 1379 school-children from Skye and Mallaig in the N.W. of Scotland failed to show evidence of subclinical cases of hydatidosis. There appeared to be a relatively low level of exposure to the parasite, as judged by ELISA and IHA tests. Thirty-one children reacted positively in the ELISA; only one child had a transient positive result in the IHA test. Surveillance of these children will be continued for the present but the duration required is uncertain. The local population appeared to be well aware of the mode of spread of the parasite and the methods for its control.
The epidemiology of hydatid disease in England and Wales
Authors: Stallbaumer M. F. , Clarkson M. J. , Bailey J. W. , Pritchard J. E.
Published: October 2009

The epidemiology of hydatid disease in man in England and Wales, based on the data collected between 1981 and 1983 at the Hydatid Reference Laboratory of the Public Health Laboratory Service, is presented. The incidence of hydatid disease was 42 cases per annum, with 2 cases per million population occurring in Wales and 0·2 per million in England. The highest prevalence was in London amongst the immigrant population. The incidence in the indigenous population was 15·5 cases per annum, with 5·6 cases per million occurring in South Powys, parts of South Wales and Herefordshire. The population most at risk is the rural, farming community in that area, but the West Midlands is also an apparent focus of the disease.
Investigations on the role of flagella in the colonization of infant mice withCampylobacter jejuniand attachment ofCampylobacter jejunito human epithelial cell lines
Authors: Newell Diane G. , McBride Harold , Dolby Jean M.
Published: October 2009

The biochemical and biological properties of the flagella ofCampylobacter jejunihave been investigated using two variants selected from a flagellate, motile clinical isolate (strain 81116): a flagellate, non-motile variant (SF-1) and an aflagellate variant (SF-2). Phenotypic and biochemical analysis of the strains and amino acid analysis of the isolated flagella suggest that the variants differed from the wild-type strain only in the absence of flagella and/or motility. The aflagellato variant poorly colonized the gastrointestinal tract of infant mice but the flagellate, non-motile variant colonized the mice as successfully as the wild-type strain.35S-labelled organisms were used to investigate the attachment of the variants to human epithelial cell monolayersin vitro. The flagellate, non-motile strain attached more efficiently to the cells than the wild-type strain or the aflagellate strain. Differences in attachment suggest that an adhesin is intimately associated with flagella ofC jejuniand that active flagella mediate only a tenuous association with host cells. This adhesin attached most efficiently to cells of intestinal epithelial origin and was not specifically inhibited by various sugars.
The mycoplasmacidal properties of sodium hypochlorite
Authors: Lee D. H. , Miles R. J. , Perry B. F.
Published: October 2009

The effect of hypochlorite concentration onMycoplasma mycoidesssp.mycoidesviability was tested under a variety of conditions. The experimental variables employed included chlorine-cell contact time, chlorine concentration, carrier system and organic loading. Initial populations of 106c.f.u./ml were killed (no survivors in 1 ml) by hypoehlorite solution containing 25 p.p.m. available chlorine in 15 s in the absence of organic load and 50 p.p.m. available chlorine in 5 min in the presence of 1% protein. Higher concentrations of hypochlorite were required to disinfect a porous carrier system in the absence or presence of protein. The results are in contrast to previous reports thatM. bovisis killed only by high hypochlorito concentrations.
A four-year survey of African swine fever in Malawi
Authors: Haresnape J. M. , Lungu S. A. M. , Mamu F. D.
Published: October 2009

A serological survey of free-ranging domestic pigs in the Central and Southern Regions of Malawi, together with laboratory data on confirmed cases of African swine fever (ASF) and data from interviews with pig owners, undertaken over a four-year period from 1981–4, has enabled the ASF enzootic area of Malawi to be identified. The area covers much of the western part of the Central Region and includes Mchinji district and parts of Kasungu, Ntchisi, Dowa and Lilongwe districts. Mortality is substantially less than 100% in outbreaks within the enzootic area but approaches 100% in outbreaks outside this area, as shown by both the serological investigation and the interview data.
An evaluation of commercially available dehydrated Rappaport-Vassiliadis medium for the isolation of salmonellae from poultry
Authors: Fricker C. R. , Quail Elaine , McGibbon Loraine , Girdwood R. W. A.
Published: October 2009

A total of 745 samples of chicken giblets was cultured to determine the relative efficiency of a commercially available Rappaport-Vassiliadis medium (RV-Oxoid). Experiments to determine the optimum inoculation ratio showed that 1:100 was superior to the other ratios tested. Comparison of RV-Oxoid with standard RV and RV-medium prepared using soya peptone (RV-soya) showed that after 24 h RV-soya was significantly better than RV-Oxoid (P< 0·05), although there was no significant difference between standard RV and RV-Oxoid. Furthermore, when the duration of incubation was extended to 48 h there was no significant difference between the three media (P> 0·25).

We conclude that RV-Oxoid is a satisfactory product for the isolation of salmoncllae from poultry, providing that it is inoculated at a ratio of 1:100 and is incubated for 48h. Its use can therefore be recommended to laboratories who wish to use a dehydrated medium.
The serological diagnosis ofMycoplasma pneumoniaeinfection: a comparison of complement fixation, haemagglutination and immunofluorescence
Authors: Rousseau S. A. , Tettmar R. E.
Published: October 2009

A total of 193 sera were examined for antibody toMycoplasma pneumoniaeby three techniques – complement fixation (CF), haemagglutination (HA) and immunofluorescence (IF), the last method being used to assess IgM, IgG and IgA antibodies. The most reliable single test for diagnosis was HA, and the most useful combination of tests was HA with IF (IgM and IgG). The IgA IF was not found to be diagnostically helpful.
Toxin production and haemagglutination in strains ofEscherichia colifrom diarrhoea in Brescia, Italy
Authors: Bisicchia R. , Ciammarughi R. , Caprioli A. , Falbo V. , Ruggeri F. M.
Published: October 2009

Two hundred and ninety-nine different strains ofEscherichia coli, isolated from 172 patients with diarrhoea and 113 healthy subjects, were examined for enterotoxin, cytotoxin and haemolysin (Hly) production and for mannose-resistant haemagglutination (MRHA) and invasive properties. Three strains proved enterotoxigenic, none enteroinvasive; cytotoxin and Hly production was shown in 25 strains from patients and in 3 from controls. Ten strains produced the cytotoxic necrotizing factor (CNF), 6 released other factors which kill cell cultures. Hly production was shown in 21 strains, 9 of which were also positive for CNF. MRHA was detected in 26% of strains from diarrhoca compared with 14% of strains from healthy people. A strong association between toxin production and MRHA was demonstrated. Serotyping results showed that the strains exhibiting virulence traits mostly belonged to serogroups commonly involved in extra-intestinal infections. The possible role of strains ofE. colishowing one or more virulence factors as opportunistic pathogens in diarrhoeal diseases is discussed.
Acquisition of genes from an O18:K1:H7 ColV+strain ofEscherichia colirenders intracranially-inoculatedE. coliK12 highly virulent for chickens, ducks and guinea-pigs but not mice
Authors: Smith H. Williams , Huggins M. B.
Published: October 2009

The virulence of intracranially-inoculated mutant forum of an O18ac:K1:H7 ColV+stain ofEscherichia coli(designated MW) that lacked different combinations of its O and K antigens and CoIV, and of anE. coliK12 strain to which these characters had been transmitted was studied in mice, chickens, ducks and guinea-pigs.

The O18+K1+Co1V+form of MW was highly virulent for chickens and mice hut the corresponding form of K12 was only highly virulent for chickens; the O18-K1-ColV-froms of both strains were of low virulence for chickens and mice. K1 was more important than O18 or ColV in determining virulence for both animal species, Ducks and guinca-pigs resembled chickens, not mice, in their response to infection with the O18+K1+ColV+from of K12.

Pathogenesis studies revealed than the virulence of the forms of MW and K12 was associated with their ability to proliferate in the central nervous system; only low numbers of organisms were found in the blood and spleen of inoculated animals.

The O18+K1+ColV+form of K12 multiplied in mouse brian and in mouse blood in eitro; its multiplication in chicken blood was partinlly inhibited. Agglutinins to this and other forms of K12 were found in chicken serum but not in mouse serum. Large doses of mouse serum given to chickens and large doeses of checken serum given to mice did not alter the manner in which these animals responded to K12 O18+K1+ColV+infection. Vaceination protected chickens and mice against lethal intraeranial infection with the O18+K1+ColV+forms of K12 or MW; it produicted a much stronger immunity in mice against intrapertoneal challenge than against intraeranial challeage
The ovine mammary gland as an experimental model to determine the virulence of animal ureaplasmas
Authors: Ball H. J. , Mackie D. P.
Published: October 2009

As an estimate of their virulence, the ability of ovine, bovine, canine, feline and simian ureaplasma strains to cause mastitis in the ovine mammary gland was investigated. Five ovine ureaplasmas produced a clinical mastitis. Broth cultures of seven bovine ureaplasmas were unable to infect the ovine gland, but two of these strains plus one other were able to do so following passage through the bovine udder. One of two canine strains and a feline strain both caused mastitis, but the simian strain persisted at low titre for only 5 days post-inoculation in one of the two ewes tested.
Transferable resistance to trimethoprim in enteric pathogens isolated in Kuwait
Authors: Chugh T. D.
Published: October 2009

Trimethoprim resistance was seen in 14·8% of 500 strains of salmonella, 43·1% of 153 strains ofshigella and 59% of 27 strains of Escherichia coli isolated from stools of patients with diarrhoea. Strains with a high level of trimethoprim resistance (MIC of ≥ 512 μg) were subjected to conjugal transfer. Trimethoprim resistance was plasmid-mediated in all of 42 strains of shigella and 12 strains of E. coli examined. However, 2 of the 47 strains of salmonella could not transfer their trimethoprim resistance either directly or by mobilization with the transfer factors X and Δ both at 37 and 25 °C overnight incubation.
Bacterial counts on fabrics: a comparative study of three methods
Authors: Hoborn Jan , Nyström Bertil
Published: October 2009

One contact plate and two homogenization methods have been compared for efficiency in assessing the bacterial contamination of fabrics with high or low, natural or artificial contamination. The contact plate method resulted in considerably lower counts than any of the homogenization methods, which closely resembled one another. One of these, utilizing a Stomacher 400®, was found to be more practical, and is therefore recommended for counting bacteria on fabrics.
The coypu as a rodent reservoir of leptospira infection in Great Britain
Authors: Waitkins Sheena A. , Wanyangu S. , Palmer M.
Published: October 2009

The coypu (Myocastor coypusMolina) is an aquatic rodent that has become a widespread pest in the south-east of England. Since the natural habitat of this animal is aquatic, the possibility of infection with leptospires was investigated. Twenty-nine coypu were trapped and examined by serological, histological and cultural methods. Of these, there was serological evidence of infection in seven coypus andLeptospira interrogansvar.Wolffiiwas isolated from a further animal. This appears to be the first report of the isolation of leptospira from a coypu in Great Britain.
Antibody status to influenza A/Singapore/1/57(H2N2) in Finland during a period of outbreaks caused by H3N2 and H1N1 subtype viruses
Authors: Pyhälä R.
Published: October 2009

The incidence of haemagglutination inhibition (HI) antibody (titre ≥ 12) to influenza A/Singapore/1/57(H2N2) in sera collected from a Finnish population in the summer of 1981 was 58%. Subjects born after 1968 were essentially seronegative, and a comparable low HI antibody status was also recorded among the elderly, lowest being in people born during the period 1901–10. A small increase in antibody titre to the H2N2 virus was observed in the different age groups after infections with the H3N2, but not the H1N1, subtype influenza A viruses. The heterotypic response, which could be due to HI or NA antibodies, was restricted almost exclusively to subjects already exhibiting this antibody in acute phase sera. Moreover, the anamnestic boosting was not as strong as that described in earlier studies from samples collected at the beginning of the present era of H3N2 viruses.At population level, the HI antibody status to H2N2 was about the same at the beginning and end of the follow-up period which covered eight epidemic seasons. The results are discussed with respect to the doctrine of ‘original antigenic sin’ and to the threat of re-emergence of the H2N2 viruses.
Epidemic Coxsackie B virus infection in Johannesburg, South Africa
Authors: Schoub Barry D. , Johnson Sylvia , McAnerney Jo M. , Santos Isabel L. Dos , Klaassen Katalin I. M.
Published: October 2009

A particularly extensive epidemic of Coxsackie B3 virus infection occurred in Johannesburg in the spring and summer of 1984. A total of 142 positive cases were diagnosed by isolation of the virus from stools and other specimens (60) or by serology (82). Coxsackie B3 accounted for 87% of the isolations and was also the dominant serotype on serology.

The outbreak involved predominantly children and young adults, with no apparent sex differences being noted. The majority of specimens came from the white population and no significant difference in age or sex distribution could be observed between the two race groups. The major clinical presentation in the white group was Bornholm disease followed by cardiac involvement and then meningoencephalitis. In the black group, however, myocarditis was the major clinical presentation, which is of particular interest taking into account the extremely high incidence of acute rheumatic carditis in this population and the prevalence of chronic cardiomyopathy.
Acute diarrhoeal disease in children under 7 years of age in a peri-urban slum of Santiago, Chile
Authors: Araya M. , Figueroa G. , Espinoza J. , Montesinos N. , Spencer E. , Brunser O.
Published: October 2009

A group of 168 families who lived in a peri-urban slum in Santiago were surveyed for 9 months. All of them had a child under 7 years of age. Medical activities and data collection were carried out at a Field Station and by means of twice-weekly visits to each home, at which time cases of diarrhoea were recorded and investigated. Faecal samples for bacteriological, parasitological and rotavirus studies were obtained during each episode. The characteristics of clinical course, hygienic practices in the family, and monthly anthropometric measurements of infants and toddlers were also recorded. The mean monthly incidence of diarrhoea was 7·1 episodes per 100 children. Of the episodes, 44·2% were associated with pathogenic bacteria, 14·4% with rotavirus, 38·4% with parasites and in 27·9% no enteropathogens were identified. It was found that adequate hygienic habits were not associated with a decreased risk of developing diarrhoea and that about 60% of children did not have diarrhoea throughout the study period. The nutritional status was adequate in most cases: weight-for-age was below the 5th percentile in 11·5% of subjects and the height-for-age was normal in all. No moderate or severe cases of malnutrition were detected.
Type A influenza (H2N2) viruses isolated in Leningrad in 1980
Authors: Golubev D. B. , Karpukhin G. I. , Galitarov S. S. , Denisov G. M.
Published: October 2009

In April-May 1980, two independent outbreaks of influenza-like illness occurred in Leningrad among children's-home children aged from 3 months to 2 years (of 68 children under observation, 50 became ill) and among boarding-school pupils aged 15–17 years (of 50 pupils under observation, 13 became ill).

A total of five influenza A virus strains were derived from one clinically healthy and three affected children of the children's home. Similar viruses were obtained from one affected boarding-school pupil and from an infected woman aged 24 years (a sporadic case within a household). On the basis of laboratory findings, all these seven strains were identified as influenza A H2N2 subtype strains.

Six of the affected children showed significant seroconversion only to H2 haemagglutinin from February to May 1980. Type A influenza H2N2 virus was isolated from three persons, including the sporadic case, who also showed significant seroconversion to H2 haemagglutinin. H2N2 influenza A virus was isolated on two occasions, at a 7-day interval, from the girl N. Ju.

Laboratory findings obtained from the study of the viruses isolated using up-to-date immunological and molecular-biochemical techniques enable us to conclude the following. The A/Leningrad/80 isolates belong to H2N2 sero-subtype. The viruses isolated are similar but not identical to the A/Singapore/I/57 reference strain in details of polypeptide and gene composition.
A method for predicting proportions of affected herds from proportions of affected animals
Authors: Leech F. B. , Wedderburn R. W. M.
Published: October 2009

The frequency of herds affected with 13 different diseases is shown to bear a simple relationship to the frequency of affected animals. The relationship seems to be useful for predicting proportions of affected herds.
The effect of two methods of cooking and cooling onClostridium welchiiand other bacteria in meat
Authors: Sutton R. G. A. , Kendall Margaret , Hobbs Betty C.
Published: October 2009

A comparison was made of beef cooked in conventional and moist air (Rapidaire) ovens. In both large (ca.4·5 kg.) and small (ca.2·7 kg.) joints, spores ofClostridium welchiisurvived after cooking but vegetative cells,Escherichia coli, andStaphylococcus aureus, did not, regardless of the type of oven used

Cooling at room temperature after cooking permitted growth ofCl. welchii. Although some multiplication also occurred in the centre of large roasts cooled under refrigeration, the viable counts were considered too low to constitute a potential health risk
IgG, IgA and IgM responses in acute rubella determined by the immunofluorescent technique
Authors: Cradock-Watson J. E. , Bourne M. S. , Vandervelde Elise M.
Published: October 2009

The indirect immunofluorescent technique has been used to study the specific immunoglobulin responses in twelve adult cases of acute uncomplicated rubella. IgG, IgA and IgM antibodies increased virtually simultaneously. IgG antibody persisted throughout the period of study but showed a slight tendency to fall in titre after 7 months. IgM antibody was detected in nine cases. In these patients it was present in high titre 5–15 days after the rash but was not detected after 20 days. IgA antibody was detected in all cases. It was present in high titre 5–20 days after the rash but was no longer detectable after 29 days except in one patient who had a very low titre at 78 days. The presence of specific IgA and IgM indicates recent rubella in uncomplicated cases, and if the immunofluorescent method is used both types of antibody should be sought.
The influence of the route of immunization on the protection of mice infected intracerebrally withBordetella pertussis
Authors: Standfast A. F. B. , Dolby Jean M.
Published: October 2009

The development of immunity in mice toBordetella pertussisinduced by intracerebral, intravenous or intraperitoneal vaccination was analysed in terms of the viable bacteria in the brain after intracerebral challenge, the serum antibodies, and protection against the sublethal infection of the lung that follows intranasal inoculation.

A vaccine introduced intracerebrally was five to ten times more effective than that given intraperitoneally or intravenously, as measured for each route by the amount of vaccine required to protect half the mice against an intracerebral challenge 14 days later (ImD50). Intracorebral vaccination induced higher antibody titres than vaccination by the other two routes. The survival of infected mice given 1–3 ImD50 doses of vaccine intracerebrally 14 days before, followed a pattern similar to that after intraperitoneal or intravenous vaccination with up to 10 ImD50 of vaccine: the numbers of organisms increased for 3 days and then declined. Injection of about four ImD50 of vaccine intracerebrally produced a local immunity, resulting in an immediate kill of challenge organisms given 14 days later. Such an effect following intraperitoneal vaccination was achieved only against challenges with an avirulent strain. It is suggested that better stimulation of circulating antibody and local immunity in the brain together account for the better protection induced by intracerebral vaccine.

Immunity to an intracerebral infection appears therefore to have at least three components, each specific for pertussis. The first, like that induced by intraperitoneal and intravenous vaccination, reaches a maximum in 2 or 3 weeks and is probably an expression of a general response by the animal operating not earlier than 3 days after infection. The second is a local immunity, appearing after the same interval. The third is a short-lived local immunity which has been described by previous workers; it immediately follows the injection intracorebrally of ten times less vaccine than that needed to protect against a challenge 14 days later and lasts only 2–3 days. The second and third types result in immediate sterilization of the infection.

Mice recovering from sublethal brain infection with avirulent organisms were immune to a second infection with a virulent organism, but this was achieved not by the ability to kill the re-infecting organisms immediately on injection into the brain, but only after the 3–4 days lag such as follows intraperitoneal vaccination.
The production of mastitis in cows by the intramammary inoculation of T-mycoplasmas
Authors: Gourlay R. N. , Howard C. J. , Brownlie J.
Published: October 2009

Six milking cows were inoculated with bovine and human T-mycoplasmas and control materials into the udder via the teat canal. Control materials produced only a slight transient cell response in the milk. Bovine T-mycoplasmas produced clinical mastitis in nine out of ten quarters inoculated. Seven developed clinical mastitis together with visible changes in the milk, excretion of T-mycoplasmas and greatly increased cell counts in the milk. In three of these quarters, in two different cows, milk secretion ceased completely. Two quarters in a different cow showed visible milk changes, excretion of T-mycoplasmas and increased cell counts. Two quarters were inoculated with human T-mycoplasmas and neither produced any signs of mastitis.

Infection of the udder with T-mycoplasmas did not stimulate high-titre serum antibody levels as measured by the metabolic inhibition test, but whey samples gave high titres in two of the cows that were able to control and resolve the infection.
Adenovirus, parainfluenza virus and respiratory syncytial virus antibodies in the sera of Jamaicans
Authors: Jennings Roy
Published: October 2009

Surveys for respiratory virus antibodies in the Jamaican population have shown that adenovirus, respiratory syncytial virus and parainfluenza types 1 and 3 virus antibodies are acquired early in life. The incidence of haemagglutination-inhibiting antibodies to parainfluonza viruses increases rapidly with age and almost all adults possess parainfluenza type 3 antibody, usually in high titre. Parainfluenza type 1 antibodies are only slightly less common. Complement-fixing antibodies to the adenovirus group were also observed to increase in incidence with age.

Complement-fixing antibody to respiratory syncytial virus was less common in Jamaican sera than antibody to the other respiratory viruses described here. The highest titres were observed in the youngest age-group.
Isolation for the control of infection in skin wards
Authors: Noble W. C. , White Pamela M.
Published: October 2009

An isolation policy in a hospital for skin diseases is reported. Patients carrying penicillin- and tetracycline-resistant organisms were to be isolated in single rooms, though barrier nursing was not practised. The policy failed because the single beds rapidly became blocked with long-stay patients and because even in a single-bed unit patients acquired staphylococci within 3–7 days of admission. Patients with skin diseases often do not feel ‘ill’ and resent isolation.
Observations on procedures for thawing and spit-roasting frozen dressed chickens, and post-cooking care and storage: with particular reference to food-poisoning bacteria
Authors: Roberts Diane
Published: October 2009

A comparison was made of four methods of thawing frozen chickens and an average thaw time for each method was determined.

Fully and partially thawed chickens, inoculated with salmonellas,Clostridium welchiiandSlaphylococcus aureuswere cooked in a spit-roasting oven at different temperatures for different lengths of time. The chickens were examined freshly cooked and after storage under various conditions.

Spit roasting fully thawed chickens until the outer skin was golden brown was sufficient heat-treatment to kill salmonellas andStaph. aureusbutCl. welchiicould survive. Salmonellas could also survive if the chickens were not fully thawed before cooking.

Incorrect storage after cooking was shown to encourage the growth of pathogens.

The incidence of intestinal pathogens in frozen dressed chickens and environmental hazards in spit-roasting establishments were also studied. Of raw chickens examined 35% contained salmonellas (9 serotypes), 63% containedCl. welchiiand 63%Staph. aureus.
An epidemiological study of strains of Shigella sonnei from two related outbreaks
Authors: Thomas Mair E. M. , Haider Yasmeen , Datta Naomi
Published: October 2009

During the winter of 1967–8 Sonne dysentery affected neighbouring North London primary schools. This was not simply due to cross-infection between the two schools, for two different, unusual strains of Sh. sonnei were distinguished. One was a novel kanamycin-resistant colicine type 7 strain, and as far as we know this was the first school outbreak due to such a strain to be documented. The other strain was kanamycin-sensitive and of colicine type 0 with a rare specific requirement for aspartic acid. There was some evidence to suggest that the kanamycin-resistant strain was more infective for adults and possibly more pathogenic than the kanamycin-sensitive.

Studies on the transfer of drug resistance and of colicinogeny revealed that the factor determining colicine type 7 was carried on a transmissible plasmid, a new observation. Various drug resistances were also transmissible experimentally, and some were spontaneously unstable. Non-transferable ampicillin-resistance in the colicine type 7 strain and aspartic acid dependence in the colicine type 0 strain enabled all but one of the isolates to be classified into two distinct lines. No common ancestor was found and it was concluded that although occurring together they must have arisen from separate sources.