bluuebunny/crossref_metadata_2025 huggingface dataset:
The laboratory evaluation of iodophor disinfectants with yeast suspensions
Authors: Charley Claire M. , Hayter Susanne E.
Published: May 2009

The report investigates the variation in results noticed when testing iodophor disinfectants in the presence of a 5% (w/v) yeast suspension.

It was found that these variations were not related to individual iodophor formulations but bore a direct relationship with the storage time of the prepared yeast suspension.
A source isolator for infected patients
Authors: Babb J. R. , Bridges Kim , Lowbury E. J. L. , Hodgson Elizabeth M. , Trexler P. C.
Published: May 2009

A plastic, mechanically ventilated source isolator with filters in the air effluent was designed to enable infected patients to be nursed and treated in a general ward or to be transported without risk to staff or other contacts.

Two models of isolator were developed. Their potential value was tested by the challenge of heavy dispersal, inside the isolator, of bacteria (a) from patients with burns, during the change of dressings, (b) from contaminated bedding during simulated bed-making, and (c) from the dispersal of a suspension of Bacillus subtilis var. globigii.

Sampling of air by slit samplers outside the isolator and, in comparable control patients, from the air of the room in which dressings were changed, showed consistently lower counts of bacteria and of Staph. aureus during dressings when the isolator was used; on removal of the isolator canopy there was, in some experiments, a considerable increase in airborne bacteria, due to residual bacteria in the isolator or to the re-dispersal of bacteria which settled on the patient and his bedding during the dressing.

Simultaneous sampling with slit samplers inside and outside the isolator during and after bed-making or dispersal of B. subtilis var. globigii showed an almost complete protection of the air outside the isolator against contamination by bacteria released inside the isolator.
A simulation spatial model of the spread of foot-and-mouth disease through the primary movement of milk
Authors: Hugh-Jones M. E.
Published: May 2009

A computer model was constructed to mimic the 1967–8 foot-and-mouth epizootic in Shropshire and Cheshire, but the daily spatial distribution of outbreaks was randomized. This pattern of outbreaks was then examined to determine what percentage of outbreaks would fulfil an arbitrary set of criteria for milk-lorry-borne disease, or the primary movement of milk. Some 21% of herds visited subsequent to a ‘source farm’ were affected, as were 4% of herds visited after any infected herd. The relevance of these results to the true risk of disease through the primary movement of milk off affected farms is discussed.
Some observations on the epidemiology of toxoplasmosis in Canada
Authors: Tizard Ian R. , Fish Norman A. , Quinn Joseph P.
Published: May 2009

Between 1961 and 1974, 11934 samples of serum were tested by the Sabin- Feldman Dye test for the presence of antibodies toToxoplasma gondii.

Analysis of high-titred sera suggested that a 6-year cycle of high disease prevalence occurred across Canada. In addition, a decline in the percentage of positive reactions occurred each year in the Fall. The suggestion that this decline was due to dry conditions during the summer months was supported by the observation that differences in the prevalence of toxoplasma infection in ten Canadian cities were related to their average summer rainfall. The significance of these observations in relation to the epidemiology of toxoplasmosis in this country is discussed. The influence of patient age on the prevalence of infection was also investigated; the results obtained suggested that at least 75% of infants with high antibody titres againstT. gondiihad obtained these antibodies by placental transfer from their mothers.
Modified Vi tests in the screening of typhoid carriers
Authors: Chau P. Y. , Chan A. C. H.
Published: May 2009

Two tests for the estimation of Vi antibody in sera were studied and their validity in the screening of typhoid carriers was assessed. One was a modified Vi haemagglutination test in which Vi-coated glutaraldehyde-fixed erythrocytes were used as the antigen and Vi antibody resistant to treatment with 2-mercaptoethanol was titrated. The other was a fluorescent Vi antibody test in which acetone-fixed bacterial Vi cells were used as the antigen and the total Vi antibody was titrated. In both tests, the antigens used were stable so that standardization of the tests would not be difficult. The modified Vi haemagglutination test was found equally sensitive but more specific in giving less false positives than the conventional Vi haemagglutination test. The fluorescent Vi antibody test was however found superior to both tests not only in giving less false positives but also in detecting more typhoid carriers.
Morphological manifestations of freezing and thawing injury in bacteriophage T4Bo
Authors: Steele P. R. M.
Published: May 2009

Electron microscopic observation of negatively stained preparations of frozen and thawed suspensions of T4Bo phage clearly separated the morphological changes produced by low-temperature salt denaturation from those produced by eutectic phase changes. Salt denaturation caused contraction of tail sheaths. Eutectic phase changes appeared to cause two separate lesions. Firstly the tail sheath was disjointed 18–22 nm. below the collar and the tail core was disjointed at 40–60 nm. below the collar, giving rise to separated heads with a small tail remnant, and separated tails in which the sheath remarkably remained in its extended form. Secondly, tears were seen in the head membranes of particles with collapsed empty heads. In all the experiments the percentage of normal phage particles counted electron-microscopically was close to the percentage of viable phage as determined by plaque assay.
Cold water, ultra-high pressure cleaning of abattoirs
Authors: Dempster J. F.
Published: May 2009

Cold water (10° C) at ultra-high pressure (38·5–49 kg/cm2) was compared with (a) hot water (65·6–82·2° C) at low pressure (4·2–5·6 kg/cm2) and (b) hot water containing a detergent (2% (w/v) sodium silicate). Seven sites were examined in a beef abattoir and six in a bacon factory.

Three surfaces in the beef abattoir had lower residual colony counts (higher reductions) after hot water/low pressure than after cold water/high pressure. However, the differences were not significant (P> 0·05). The range of the mean log10count/cm2before cleaning was 4·02–5·15, and after cleaning 1·73–2·32 (hot water) and 1·9–2·85 (cold water).

On three of the remaining sites, the three methods were compared. The total differences between treatments were not significant (P> 0.05), although there was an effect of surface and an interaction between surface and treatment. The cold water produced lower residual counts on three sites in the bacon factory than the hot water (45–54°C). However, the differences were not significant on the remaining surfaces.
Hospital Salmonella Johannesburg infection and its possible role in the community spread of the infection in Hong Kong
Authors: Teoh-Chan C. H. , Chau P. Y. , Tse Doris , Sin W. K. , IP H. M. H. , Lan R.
Published: May 2009

Salmonella johannesburg (1, 40: b: e, n, x), a previously rare salmonella serotype, has established itself rapidly as an important and highly prevalent cause of gastroenteritis among children. The clinical features of the infection are usually mild but chronic. It has been suggested that S. johannesburg was introduced into Hong Kong through imported foods but no common vehicle could be traced as the source of infection. A thorough investigation of one paediatric ward in a general hospital revealed that non-infected patients admitted to the ward usually acquired S. johannesburg infection within 3–7 days, with or without symptoms. Thus hospital cross-infection could be a significant factor in contributing to its rapid spread in the community. Furthermore, the rapidity with which S. johannesburg spread was facilitated by (a) its tendency to produce a chronic infection, (b) its multiple resistance to antibiotics, and (c) the higher infectivity of S. johannesburg over other salmonellas endemic in this locality. These factors combined with the overcrowded conditions in many of the hospitals in Hong Kong facilitated the occurrence of hospital infection, which in its turn contributed to the spread of the infection in the local community.
Vitamin B1 Excretion on a Varied Intake
Authors: Margaret D. , M.B. Wright, , Baker Audrey Z.
Published: May 2009

HArris & LEong (1936) found that vitamin B1; adsorbed from urine, could be measured by the rat bradycardia method of assay. The amount of vitamin B1 excreted was found to correspond in general with both the dietary intake and the physiological state of the subjects.
Papillary Variation in Coliform Bacteria
Authors: Stewart F. H.
Published: May 2009

Papillaryvariation includes all heritable changes of character which take place in the papillae of bacterial colonies and the corresponding variations in liquid media.

The following is a short summary of what is known about these variations. Papillary variation was first observed inB. coli-mutabile, and other coliform bacteria show the same variations. This race forms white colonies on lactose neutral-red plates. After 1–5 days’ incubation minute papillae, which become red and increase in size, appear on their surfaces. Subcultures from thesepapillae give colonies of two kinds, white and red. The white colonies continue to throw red, the reds breed true (Neisser, 1906; Massim, 1907). Similar variation to different sugars occurs in other related bacteria:B. dysentenaeSonne varies to lactose,B. dysentenaeMexner to maltose,B. paracolonto saccharose,B. coh-mutabile, B. acidi-lacticiandB. typhosusto dulcite (Twort, 1907; Reiner Miiller, 1909; Burn, 1910; Stewart, 1926, 1927). Vacation takes place only on the sugar concerned, but, once it has taken place, the character remains fixed, even after long growth on other media. Variation is not determined by length of exposure to the sugar. It occurs at (or after) the end of the logarithmic phase. If this phase is kept going by daily subculture (in the appropriate sugar) the bacteria of the chain carried on from culture to culture do not vary, however long they are exposed (Stewart, 1927; Deere, Dulaney & Michelson, 1939). On the other hand, if the logarithmic phase is curtailed by heavy inoculation of a culture, variation occurs early (Stewart, 1927). If the bacterium is grown on a plate without sugar until the colonies are well formed and the sugar is then added, with care not to disturb the colonies, variants appear after very short exposure (Stewart, 1927, 1928). A variation 33–2 may be completed in, two distinct steps; thus a race ofB. typhosusformed white colonies on dulcite with pink papillae, subcultures from which gave white and pink colonies; the pink colonies formed dark red papillae from which on subculture came pink and dark red colonies, the latter bred true.
The St. Andrews Marine Laboratory (under the Fishery Board for Scotland)
Authors: Prof. McIntosh
Published: May 2009

St. Andrews as a site for the study of marine animals has a reputation probably at least as ancient as the foundation of its University (the oldest Scottish, viz. 1411), for amongst the early records of the latter allusion is made to the marvels of the sea and its inhabitants as a means for improving the minds of its students. For a long time, however, no special lectures on natural history were given. The scientific advantages of the situation, indeed, were first prominently recognised by Edward Forbes and the brothers Goodsir. Thus the former, for instance, picked up, for the first time in Britain Echiurus, on the sands after a storm; and the two Goodsirs, as students, were familiar with its marine rarities, and afterwards read many zoological papers at its Literary and Philosophical Society. Prof. John Reid, the physiologist, studied the development of zoophytes and mollusks in its rock pools, and Prof. G. E. Day, his successor in the Chair of Anatomy and Physiology, and Miss Otté, lost no opportunity of interesting the students in marine zoology. Besides, the occupants of the Chair of Natural History from its foundation in 1753, and including Professors Vilant, Dick, Forrest, Cleghorn, Adamson, Ferrie, Macdonald, and Nicholson, as well as Dr. McVicar, the University lecturer, all more or less drew from the rich marine resources in their proximity.
The Scottish Marine Station and its Work
Authors: Hoyle William E.
Published: May 2009

The “Scottish Marine Station for Scientific Research” has now been at work for a little over four years, so that the present seems a fair opportunity to inquire what has been accomplished by its means. The object of the present article is to supply this information, and to show to what extent the results obtained have justified the expectations of its promoters.
Distribution patterns and reproduction of the cuttlefish, Sepia officinalis in the Sado estuary (Portugal)
Authors: Neves A. , Cabral H. , Sequeira V. , Figueiredo I. , Moura T. , Gordo L.S.
Published: May 2009

The cuttlefish (Sepia officinalis) is the most important traditional fishing activity in the Sado estuary. In order to analyse the spatial and temporal distribution patterns and to study the reproductive cycle of this species, twenty sampling areas were towed along the estuary on a monthly basis from May 2001 to April 2002. The higher densities were obtained in summer and autumn in the lower and southern area of the estuary while spring showed the higher biomass. Mature individuals prevailed in the inner zone of the estuary during spring while juveniles were dominant in autumn and concentrated in the lower part of the estuary. Almost all individuals leave the estuary during winter. The weight–length relationship was significantly different according to sex, being females heavier than males for individuals larger than 106 mm. Sex-ratio was similar to 1:1 in every season. Females had high values of gonadosomatic index during the spawning season with a major peak in June, while males showed similar values throughout the spawning season. The length at first maturity was estimated at 80 mm mantle length (ML) for females and 59 mm ML for males. In the Sado estuary only one generation of cuttlefish breeders were found with an average of 110 mm ML for males and 122 mm ML for females, which is consistent with breeders in their first year.
Optimal plane beams modelling elastic linear objects
Authors: Koh Sung K. , Liu Guangjun
Published: May 2009

This paper discusses analytical and deterministic models for a plane curve with minimum deformation that may be utilized in planning the motion of elastic linear objects and investigating the inverse kinematics of a hyper-redundant robot. It usually requires intensive computation to determine the configuration of elastic linear objects. In addition, conventional optimization-based numerical techniques that identify the shape of elastic linear objects in equilibrium involve non-deterministic aspects. Several analytical models that produce the configuration of elastic linear objects in an efficient and deterministic manner are presented in this paper. To develop the analytical expressions for elastic linear objects, we consider a cantilever beam where the deflections are determined according to the Euler–Bernoulli beam theory. The deflections of the cantilever beam are determined for prescribed constraints imposed on the deflections at the free end to replicate various elastic linear objects. Deflections of a cantilever beam with roller supports are explored to replicate elastic linear objects in contact with rigid objects. We verify the analytical models by comparing them with exact beam deflections. The analytical model is precisely accurate for beams with small deflections as it is developed on the basis of the Euler–Bernoulli beam theory. Although it is applied to beams undergoing large deflections, it is still reasonably accurate and at least as precise as the conventional pseudo-rigid-body model. The computational demand involved in using the analytical models is negligible. Therefore, efficient motion planning for elastic linear objects can be realized when the proposed analytical models are combined with conventional motion planning algorithms. We also demonstrate that the analytical model solves the inverse kinematics problem in an efficient and robust manner through numerical simulations.
Comparison of pulsed-field gel electrophoresis and ribotyping for subtyping ofVibrio choleraeO139 isolated in Thailand
Authors: Dalsgaard A. , Skov M. N. , Serichantalergs O. , Echeverria P.
Published: May 2009

Pulsed-field gel electrophoresis (PFGE) ofCpoI-digested genomic DNA and ribotyping (BglI) were applied to 60Vibrio choleraestrains including 48V. choleraeO139 from Thailand to compare their value in differentiating strains of the presentV. choleraeO139 epidemic. PFGE patters were divided into groups A and B representing five and four subtypes, respectively, while ribotyping showed four different patterns. PFGE group B subtypes were only presented among O139 isolates from Thailand, whereas four O139 strains from Bangladesh and India showed identical PFGE group A subtypes observed in O139 isolates from Thailand. Two nontoxigenic O139 isolates from Thailand showed different and unique PFGE types as did fiveV. choleraenon-Ol non-O139 isolates containing a gene virulence complex found inV. choleraeO139. These results indicate that PFGE (CpoI) can resolve recent evolutionary divergence withinV. choleraeO139 and offers a useful supplementary tool for following the progressingV. choleraeO139 epidemic.
World Health Organisation – supervised interlaboratory comparison of ELISAs for the serological detection ofSalmonella entericaserotype Enteritidis in chickens
Authors: Barrow P. A. , Desmidt M. , Ducatelle R. , Guittet M. , van der Heijden H. M. J. F. , Holt P. S. , Huis in't Velt J. H. J. , McDonough P. , Nagaraja K. V. , Porter R. E. , Proux K. , Sisak F. , Staak C. , Steinbach G. , Thorns C. J. , Wray C. , van Zijderveld F.
Published: May 2009

A collaborative exercise, supervised by the World Health Organisation, was set up to compare ELISAs used for the serological detection ofSalmonella enteriticaserotype Enteritidis in chickens. The aim was to ascertain how far agreement could be reached on the interpretation of optical density readings for high titre, intermediate titre and low titre sera. Two sets of sera were sent to 14 participants. The first set compared high, medium and low titre sera raised in specified-pathogen-free and commercial broiler breeder chickens. The second set comprised 20 sera of different antibody titres raised in commercial birds reared under laboratory conditions and sent blind. Both indirect and double-antibody sandwich blocking ELISAs were used with a number of different detecting antigens. With a few exceptions good agreement was reached on the interpretation of results obtained from high and low titre sera from the optical density obtained with a single serum dilution. Differences were observed in the interpretation of medium titre sera. The results suggested that most ELISAs produce reasonably comparable results and that practical problems may arise from interpretation of the results mainly as a result of the choice of the criteria used for differentiating sera obtained from infected and uninfected chickens. These problems are discussed.
Antibiotic prescribing during an outbreak of meningococcal disease
Authors: Stuart J. M. , Robinson P. M. , Cartwright K. , Noah N. D.
Published: May 2009

During a prolonged outbreak of meningococcal disease caused by serogroup B serotype 15 sulphonamide-resistant strains in one British health district, there was considerable variation in attack rates by town. General practitioner (GP) antibiotic prescribing rates were compared in high and low incidence towns. The only significant difference found was that erythromycin prescribing was more frequent in the high incidence towns (rate ratio 4·0, 95% CI 3·2–4·8, in March 1987 and 3·0, 95% CI 2·4–3·7, in November 1987). This was probably due to increased GP consultation rates for upper respiratory tract infection (URTI), but higher erythromycin usage may have increased meningococcal acquisition rates or susceptibility to meningococcal disease. Antibiotic prescribing rate should be further investigated in defined areas of high and low incidence of meningococcal disease.
Respiratory syncytial virus infection and meningococcal disease
Authors: Stuart J. M. , Cartwright K. , Andrews N. J.
Published: May 2009

Although viral respiratory tract infections may predispose to meningococcal disease, strong evidence that they do so exists only for influenza. Data on laboratory reported cases of respiratory syncytial virus (RSV) infections and meningococcal disease in England and Wales from mid-1989 to mid-1994 were analysed. Although the rise in RSV cases preceded the rise in meningococcal disease cases each winter, the interval between the rise and fall of the two diseases was inconsistent, no association was found between time series after removal of the seasonal component, and there was no evidence that more cases of meningococcal disease occurred in winters with more RSV disease. RSV may have less effect on the two most likely mechanisms whereby influenza predisposes to meningococcal disease, namely lowered immunity and impaired pharyngeal defences.
Microbiology of HIV associated bacteraemia and diarrhoea in adults from Nairobi, Kenya
Authors: Batchelor B. I. F. , Kimari J. N. , Brindle R. J.
Published: May 2009

We undertook a retrospective descriptive comparison of the spectrum of pathogens responsible for bacteraemia and diarrhoea in HIV antibody positive and negative patients over 4 years (1988–92), in Nairobi, Kenya. The study population was recruited from primary to tertiary centers of clinical care and consisted of 2858 adults (15 years or older). There were 415 significant blood culture isolates, 192 from 1785 HIV negative patients and 223 from 953 HIV positive patients. There were 233 significant faecal isolates, 22 from 115 HIV negative patients and 211 from 531 HIV positive patients. The most common pathogens detected in blood were Streptococcus pneumoniae and Salmonella typhimurium and in faeces Shigella flexneri, S. typhimurium and Cryptosporidium parvum. The agents causing illness in HIV positive patients in Nairobi are similar to those prevalent in the HIV negative community and the investigation of a febrile illness with or wothout diarrhoea in an HIV positive patient should reflect this.
Impact of incomplete coverage of neonatal dried blood spot screening on estimating HIV-1 seroprevalence
Authors: Hutchinson E. J. , Streetly A. , Grant C. , Pollitt R. , Eldridge P. , Nicoll A.
Published: May 2009

The aim of this study was to determine the extent to which selective under-coverage of births to mothers more likely to be at risk of HIV-1 infection will result in a significant underestimation of the true neonatal seroprevalence. Census data, local birth statisties, maternity data and data from the prevalence monitoring programme were used to produce a model to predict the effects of under-coverage in the uptake of neonatal metabolic screening which has been observed in babies with a mother of ethnic group black African. The adjustment factor which allows for under-coverage is the relative inclusion ratio (RIR); the probability that samples from a group at different risk of HIV infection were included in the survey divided by the probability of inclusion for samples from all other babies. The RIR was found to be close to unity (0·97), indicating a minimal bias. Under usual conditions only if the relative inclusion ratio (RIR) declined to values of 0·87 or below would there be a substantial bias. Despite some selective under representation, the results obtained from the Unlinked Anonymous HIV Monitoring Programme Dried Blood Spot Survey would seem to identity levels of prevalence in the population of child-bearing women with a good degree of accuracy and remains a useful tool for resource allocation, planning of services, provision of care and counselling.
The incidence ofCyclospora cayetanensisin stool samples submitted to a district general hospital
Authors: Clarke S. C. , McIntyre M.
Published: May 2009

Cyclospora cayetanensisis the cause of a prolonged diarrhoeal syndrome. In the UK most cases are seen in travellers who have returned from countries in which the organism is endemic. The purpose of this investigation was to determine the incidence ofC. cayetanensisin stool samples submitted to a district general hospital. A total of 6151 stools from 5374 different patients were screened for the presence ofC. cayetanensisover a 1-year period using the modified Ziehl-Neelsen technique. Oocysts ofC. cayetanensiswere found in 7 stools (0·1%) from 4 patients (0·07%). All four patients were adult travellers who had visited countries in whichC. cayetanensisis known to be endemic. In the population of this study,C. cayetanensiswas found to be a rare cause of diarrhoea. AlthoughC. cayetanensisinfection should be considered in individuals of all ages who have lived in, or have travelled to endemic areas, there is no need to screen stool samples for the organism in those without such a travel history.
Increased colonization potential of Campylobacter jejuni strain 81116 after passage through chickens and its implication on the rate of transmission within flocks
Authors: Cawthraw S. A. , Wassenaar T. M. , Ayling R. , Newell D. G.
Published: May 2009

The mechanisms by which Campylobacter jejuni rapidly spreads through large broiler flocks are unknown. Recent evidence suggests that the minimum infective oral dose for 100% caecal colonization is about 104 cfu, which, with such a ‘fragile’ organism, may limit transmissibility. However, the colonization potential of laboratory-adapted strains may be anomalous compared with fresh isolates or those passaged in vivo. The colonization potential of two chicken and one human C. jejuni isolates, which were minimally passaged, have been investigated using a quantitative model of chicken colonization. There was no detectable difference between these strains but all were more efficient colonizers than a laboratory-adapted strain 81116. In addition, the colonization potential of C. jejuni strain 81116 following a passage in vivo was also determined. The results indicated this increased C. 10000 fold following a single passage in vivo, such that a dose of only 40 cfu caused maximal colonization. Enhanced colonization potential may, therefore, account for the rapid rate of transmission within large flocks.
Foal diarrhoea between 1991 and 1994 in the United Kingdom associated withClostridium perfringens, rotavirus,Strongyloides westeriandCryptosporidiumspp.
Authors: Netherwood T. , Wood J. L. N. , Townsend H. G. G. , Mumford J. A. , Chanter N.
Published: May 2009

A case control study of foal diarrhoea in the United Kingdom was carried out over a 3-year period.Clostridium perfringenswas significantly associated with foal diarrhoea (Odds Ratio (OR) = 3·0), being isolated from 57% of 421 animals with diarrhoea but from only 27% of 223 healthy foals. Also,C. perfringenswas significantly associated with fatal diarrhoea (OR = 4·5). About half of diarrhoea with a fatal outcome was attributable to this organism.

The other pathogens significantly associated with diarrhoea were rotavirus (OR = 5·6), Cryptosporidium spp. (OR = 3·2) and the nematodeStrongyloides westeri, which was significant only when present in large numbers (> 2000 eggs/g of faeces: OR = 6·1).Salmonellaspp. (OR = 14·2) andCryptosporidiumspp. (OR = 3·0) were the only other pathogens associated with fatal illness.

Overall,C. perfringens, rotavirus, and large numbers ofCryptosporidiumspp. orS. westeriwere isolated from 80% of foals with diarrhoea. ThermophilicCampylobacterspp.,Yersinia enterocolitica,Escherichia coliand other parasites were not associated with diarrhoea. Carriage ofC. perfringens, rotavirus andCryptosporidiumspp. was significantly greater in healthy foals in contact with cases of diarrhoea than in foals that were not in contact with diarrhoea (P < 0·05). There were no statistical interactions between any of the pathogens associated with diarrhoea although separate cases from one location often involved more than one pathogen.
The use of alkalinity and incubation at 9 °C for improved recovery ofYersiniaspp. from faeces
Authors: Greenwood Melody H. , Hooper W. L.
Published: May 2009

Recovery ofYersinia enterocoliticaand related strains from faecal samples enriched in 1% buffered peptone water (pH 7·2) and incubated at 4 °C for 17–21 days was compared with recovery from 1% peptone water buffered to pH 8·0 and incubation over the temperature range 4–26°C. Best recovery was obtained by use of the alkaline medium incubated at 9°C. Greatest recovery was obtained after incubation for 10–14 days, but most strains (> 75%) were recovered after 1 week.
Species identification, antibiotic sensitivity and slime production of coagulase-negative staphylococci isolated from clinical specimens
Authors: Deighton M. A. , Franklin J. C. , Spicer W. J. , Balkau B.
Published: May 2009

Two hundred and seventy-five consecutive clinical isolates of coagulase-negative staphylococci, including strains associated with disease, contaminants and skin colonizers, were speciated, tested for slime production and for their sensitivity to a range of antibiotics.Staphylococcus epidermidiswas the most commonly identified species, comprising 63% of all isolates. Slime production was detected in half the strains ofStaph. epidermidis, Staph. haemolyticusandStaph. Saprophyticusbut was rare in other species. MostStaph. haemolyticusstrains and approximately half of theStaph. epidermidisstrains were resistant to five or more antibiotics. A significant association was found between slime production and multiple antibiotic resistance. For catheter-associated strains, clinical relevance was predictable by species i.e.Staph. epidermidis. Multi-resistant slime-positiveStaph. haemolyticusstrains, although infrequently associated with disease, were common skin colonizers, presumably acquired from the hospital environment. We describe a practical and inexpensive scheme for thespeciation of human coagulase-negative staphylococcal isolates.
Prospective study of diarrhoeal disease in a cohort of rural Mexican children: incidence and isolated pathogens during the first two years of life
Authors: Cravioto Alejandro , Reyes Rosa E. , Ortega Roberto , Fernández Guadalupe , Hernández Raymundo , López Dolores
Published: May 2009

Colonization of the intestine by putative pathogens was followed longitudinally in a cohort of 56 infants born during one calendar year in a rural Mexican village with faecal cultures taken every fortnight and every time a child had diarrhoea. The frequency of isolation of pathogens during episodes of diarrhoea was compared with that of matched controls from the same cohort. Incidence of diarrhoea during the first year of life was 98%, diminishing to 93% during the second year. The incidence curves for each year were not significantly different (P> 0·1). Isolation of enteropathogenicEscherichia coli, enterotoxigenicEscherichia coliproducing heat-stable (ST) and/or heat-labile (LT) enterotoxins and rotaviruses was significantly higher in infants with diarrhoea during the first 2 years of life. In the case of shigella, although no significant differences were found by semester of life, 13 of 16 children in which these strains were found had diarrhoea. Isolation ofSalmonellaspp.,Campylobacterspp. and protozoa were not significantly different in the two groups during the period studied. Strains showing localized adherence to HEp-2 cells or the presence of colonization factor antigens I or E8775 were found with significantly higher frequency in children with diarrhoea. Eighty-two percent of ST+or LT+ETEC strains isolated produced one of the three known colonization factors.
Washing with contaminated bar soap is unlikely to transfer bacteria
Authors: Heinze John E. , Yackovich Frank
Published: May 2009

Recent reports of the isolation of microorganisms from used soap bars have raised the concern that bacteria may be transferred from contaminated soap bars during handwashing. Since only one study addressing this question has been published, we developed an additional procedure to test this concern. In our new method prewashed and softened commercial deodorant soap bars (0·8% triclocarban) not active against Gram-negative bacteria were inoculated withEscherichia coliandPseudomonas aeruginosato give mean total survival levels of 4·4 × 105c.f.u. per bar which was 70-fold higher than those reported on used soap bars. Sixteen panelists were instructed to wash with the inoculated bars using their normal handwashing procedure. After washing, none of the 16 panelists had detectable levels of either test bacterium on their hands. Thus, the results obtained using our new method were in complete agreement with those obtained with the previously published method even though the two methods differ in a number of procedural aspects. These findings, along with other published reports, show that little hazard exists in routine handwashing with previously used soap bars and support the frequent use of soap and water for handwashing to prevent the spread of disease.
Ontogenesis of the formation of secretory antibodies to respiratory syncytial (RS) virus
Authors: Leschinskaya N. P , Pokrovskaya E. E , Kantorovitch E. A , Grigorjeva S.K , Shvartsman YA. S
Published: May 2009

Examination of sera from 184 children aged between 0 and 12 years and 161 adults revealed a close correlation between age and the level of humoral anti-RS virus immunity. Secretory IgG antibodies were found in children in their first months of life. Evidence for their release into secretions from the serum was obtained. This might explain the positive correlation between serum antibody levels in women recently confined with the morbidity due to RS virus in children during their first months of life. Secretory IgA antibodies were found from 4 months untill old age. The secretions of children and adults contained virus-neutralizing activity which was non-immunoglobulin in nature, as well as antibodies. However, in contrast to secretory antibody this material did not prevent development of severe RS virus infections.
Nosocomial legionella pneumonia: demonstration of potable water as the source of infection
Authors: Ruf B. , Schürmann D. , Horbrach I. , Seodel K. , Pohle H. D.
Published: May 2009

From January 1983 until December 1985, 35 cases of sporadic nosocomial legionella pneumonia, all caused byLegionella pneumophila, were diagnosed in a university hospital.L. pneumophilaserogroup (SG) 1 was cultured from 12 of the 35 cases and compared to correspondingL. pneumophilaSG 1 isolates from water outlets in the patients' immediate environment by subtyping with monoclonal antibodies. The corresponding environmental isolates were identical to 9 out of 12 (75%) of those from the cases. However, even in the remaining three cases identical subtypes were found distributed throughout the hospital water supply. From the hospital water supply four different subtypes ofL. pneumophilaSG 1 were isolated, three of which were implicated in legionella pneumonia. Of 453 water samples taken during the study 298 (65.8%) were positive for legionellae. Species ofLegionellaother thanL. pneumophilahave not been isolated. This may explain the exclusiveness ofL.pneumophilaas the legionella pneumonia-causing agent. Our results suggest that the water supply system was the source of infection.
Laboratory diagnosis ofMycoplasma pneumoniaeinfection: 1. Direct detection of antigen in respiratory exudates by enzyme immunoassay.
Authors: Kok T. W. , Varkanis G. , Marmion B. P. , Martin J. , Esterman A.
Published: May 2009

Direct and indirect antigen capture enzyme immunoassays (Ag-EIA) have been developed for the detection ofMycoplasma pneumoniaein nasopharyngeal aspirates or sputum from respiratory infection. The sensitivity of the two Ag-EIA were similar, but the indirect method using polyclonal rabbit and guinea-pig antisera was more convenient. The Ag-EIA had a detection limit of 104–4·5colony-forming units/ml of sample. It was specific for M. pneumoniae and gave a low level response with M. genitalium. There were no cross-reactions with 10 other species of mycoplasmas. Tests with a wide range of bacteria and chlamydia group antigen, representing agents sometimes found in the respiratory tract, were also negative. At the current level of development, the Ag-EIA detected about 90% of specimens that were also positive for culture; 43% of specimens from culture-negative-seropositive patients gave a positive result. The overall pattern of results indicated that while antigen detection is a quick and effective substitute for the slow culture method, serological examination for specific IgM antibody is also necessary to give a complete diagnostic coverage.
Genetic relationships amongEscherichia coliisolates causing urinary tract infections in humans and animals
Authors: Whittam Thomas S. , Wolfe M. L. , Wilson R. A.
Published: May 2009

Genetic variation in isolates ofEscherichia coliobtained mostly from urinary tract infections in humans and domesticated animals (dogs and cats) was assessed for 16 enzymes using multilocus enzyme electrophoresis to characterize chromosomal genotypes. A total of 148 isolates comprised 63 distinct electrophoretic types (ETs) and about half of the isolates belonged to one of 9 common ETs. A bootstrap analysis of genetic distance between ETs revealed three significant groups of strains. Variation in allele frequencies among groups accounted for 40% of the total genetic diversity. The majority of the common ETs fell into a major cluster of closely related strains. The recovery of multiple isolates of the same electrophoretic types and serotypes from unassociated hosts suggests that these bacteria represent uropathogenic clones that are widely disseminated in humans and animals
Serotyping studies of campylobacter from naturally colonized chickens
Authors: Sjören Eva , Kaijser Bertil
Published: May 2009

Campylobacter jejuni/colistrains from 164 chickens were serotyped by the methods previously described by Penneret al.and Lioret al.The chickens were sampled during breeding from hatching to the age of 42 weeks. The birds were housed, in two separate groups, under different environmental conditions, (for comparison of the effect of hygienic precautions on the transmission of the bacteria during breeding). In the group where the hygienic conditions could be controlled to a greater extent, the chickens became colonized later in the breeding chain and with only one single campylobacter strains.
Characterization of Palyam serogroup orbiviruses isolated in South Africa and serologic evidence for their widespread distribution in the country
Authors: Whistler T. , Swanepoel R. , Erasmus B. J.
Published: May 2009

The finding that there had been multiple isolations of Palyam serogroup orbiviruses from aborted cattle fetuses in neighbouring Zimbabwe, suggested that there was a need to investigate the possible occurrence of the viruses in South Africa. Unidentified viruses isolated in South Africa, which had been in storage, were examined. Four viruses which had been isolated fromCulicoidesmidges collected at various sites in the years from 1969 to 1977, were identified as three strains of Gweru virus and one of the Nyabira virus (Palyam group serotypes originally described from Zimbabwe) A fifth virus, isolated in 1967 from the blood of a cow with mild fever, was found to be a distinct new member of the Vellore antigenic complex of the Palyam serogroup and was named Apies River virus. Sera from 476 cattle, 150 sheep, 24 goats and 78 humans from 10 farms were tested for neutralizing antibodies to the above three serotypes of virus plus Abadina and Marondera serotypes. Only 1 of 100 cattle sera from two farms in the southern coastal area had antibody, but elsewhere there was a high prevalence of antibody with 254 (53%) of all cattle exhibiting activity for one or more of the five serotypes of virus tested. Only 6 (4%) sheep, 3 (12–5%) goats and 11 (14%) humans had antibody.
HIV infection in England and Wales: a changing pattern
Authors: Taylor H. L. , Mortimer P. P.
Published: May 2009

Of 32983 specimens from 307 sources in England and Wales tested in the Virus Reference Laboratory for anti-HIV between 1984 and 1987, 6491 (20%) were positive. Ninety-five per cent of the positive subjects were male and 44% of them were from three London genito-urinary medicine clinics. In 1987 the numbers of newly diagnosed HIV infections decreased in homosexual men and haemophiliacs and increased in injecting drug abusers; 148/119 (12%) of all the positive findings in 1987 were in females. Between 1984 and 1987 the proportion of anti-HIV positive individuals who were asymptomatic fell by nearly 10% and the proportion with AIDS/ARC rose by nearly 10%. Of the requests leading to positive results 1280 (20%) were recognized as duplicates of previous positive results, while for 34 % of the requests no clinical information was provided. These deficiencies in the data compromise HIV surveillance based on diagnostic testing, and supplementary bias-free data are needed.
Properties of Vero cytotoxin-producingEscherichia coliof human and animal origin belonging to serotypes other than O157: H7
Authors: Dorn C. R. , Scotland S. M. , Smith H. R. , Willshaw G. A. , Rowe B.
Published: May 2009

Eight non-O157: H7 Vero cytotoxin (VT)-produeingEscherichia coli(VTEC) strains isolated from ill persons and nine bovine and lamb strains of serogroups matching the human strains, were characterized for various properties known to be associated withE. colivirulence. Five different serogroups were represented: O5. O55, O103, O111 and O153. The bovine and lamb strains produced VT1, while 3 human strains produced VT1, 3 produced VT2 and 2 were positive for both VT1 and VT2. The strains were non-haemolytic on horse blood agar, did not produce either heat stable toxin A (STA) or heat labile toxin (LT), and were non-invasive. The CVD419 probe which has been proposed to identify enterohaemorrhagicE. coli(EHEC) hybridized with all of the 05 and 0103 strains, none of the 055 and 0153 strains, and 3 of the 4 0111 strains. The strains carried several different sized plasmids and hybridization of Southern blots with the CVD419 probe identified plasmids ranging in size from 42 × 10 to 90 × 10. The strains did not hybridize with the enteroadherence factor (EAF) probe derived from an enteropathogenic strain and associated with the ability to give localized adherence to HEp-2 cells. Nevertheless five of the strains adhered in a localized pattern to HEp-2 cells and Intestine 407 cells. Adhesion to either HEp-2 or Intestine 407 cells did not correlate with hybridization with the CVD419 probe or haemagglutinating properties.
Tuberculosis: the disease and its epidemiology in the badger, a review
Authors: Cheeseman C. L. , Wilesmith J. W. , Stuart F. A.
Published: May 2009

The data accumulated from 1972 to 1987 on the distribution and prevalence of tuberculosis in the badger population in Great Britain is reviewed. The current information on the influence of Mycobacterium bovis infection on badger population dynamics and its clinical effect on badgers is also summarized.
Occupational exposure toStreptococcus suistype 2
Authors: Robertson I.D. , Blackmore D.K.
Published: May 2009

Antibody titres toStreptococcus suistype 2 were measured with an enzyme linked immunosorbent assay (ELISA) in four occupational groups in New Zealand. No veterinary students, 9% of dairy farmers. 10% of meat inspectors and 21% of pig farmers were seropositive toS. suistype 2. The development of antibody toS. suistype 2 was associated with occupational contact with pigs or their meat products. Subclinical infection withS. suistype 2 appears to occur in humans and the antibody produced is of only short duration. The annual incidence of subclinical infection and seroconversion in pig farmers may approach 28%. ThusS. suistype 2 may be one of the most infectious potentially zoonotic agents present in New Zealand, although very rarely resulting in clinical disease.
High-level vancomycin-resistant enterococci causing hospital infections
Authors: Uttley A. H. C. , George R. C. , Naidoo J. , Woodford N. , Johnson A. P. , Collins C. H. , Morrison D. , Gilfillan A. J. , Fitch L. E. , Heptonstall J.
Published: May 2009

Nosocomial infection or colonization due to enterococci with high-level resistance to vancomycin (minimal inhibitory concentrations [MICs] between 64 and > 2000 mg/L) has occurred in 41 patients with renal disease. These vancomycin-resistant enterococci were cultured from many sources including blood. All but one strain contained one or more plasmids ranging in molecular weight from 1·0 to 40 Megadaltons (MDa). Vancomycin resistance was transferable by conjugation to a susceptible recipient strain ofEnterococcus faecalisbut this was not always associated with plasmid DNA. The emergence of transferable high-level vancomycin resistance in enterococci causing significant clinical infections is of particular importance since vancomycin is widely regarded as a reserve drug for the management of infections with multi-resistant Gram-positive organisms.
Occurrence of drug-resistant bacteria in communal well water around Port Harcourt, Nigeria
Authors: Ibiebele D. D. , Sokari T. G.
Published: May 2009

A total of 108 raw water samples was collected from 36 wells at nine shanty settlements around Port Harcourt, Nigeria, over a period of 7 months. Samples were analysed for their bacteriological quality. Selected bacterial strains isolated from the samples were tested for their susceptibility to ten commonly used antibiotics. The organisms isolated includePseudomonasspp.,Klebsieilaspp.,Staphylococcusspp.,Proteusspp.,Enterococcus faecalis,Aeromonasspp.,Escherichia coli,Chromobacteriumspp.,Flavobacteriumspp., andSerratiaspp.

Out of 300 strains tested, 23 (6·9%) were susceptible to all the antibiotics, 277 (92·3%) were resistant to at least one antibiotic and 232 (77·3%) were resistant to two or more antibiotics. The epidemiological significance of these results is discussed.
Necrobacillosis and immunity in mice
Authors: Smith G. R. , Wallace L. M. , Till D.
Published: May 2009

The study arose from the recent finding that sub-lethal numbers of certain bacterial species greatly enhanced the infectivity of Fusobacterium necrophorum.

A severe F. necrophorum infection in mice, cured with metronidazole, produced significant though slight resistance, which was demonstrable by challenge with a minute dose of F. necrophorum (< 20 organisms) suspended in a sub-lethal dose of Escherichia coli (300 × 10 organisms) to enhance fusobacterial infectivity. In an earlier comparable experiment, challenge with F. necrophorum alone, in necessarily large doses (≥3 × lO organisms), failed to demonstrate that a single cured fusobacterial infection gave rise to resistance; such an infection neither protected against the fatal necrobacillosis produced by challenge nor prolonged survival.

A sub-lethal E. coli infection was also shown by challenge with a minute dose of F. necrophorum (< 10 organisms), suspended in a sub-lethal dose of E. coli (152 × 10 organisms), to produce significant though slight protection against necrobacillosis.

The degrees of resistance demonstrated were too slight to give any encouragement to the prospect of an effective necrobacillosis vaccine.