bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepatitis B markers in West Yorkshire firemen
Authors: Crosse B. A. , Teale C. , Lees E. M.
Published: May 2009

Firemen have been considered at occupational risk of hepatitis (HBV) infection, but proof is lacking. The aim of this study was to assess the degree of risk by determining the prevalence of serological markers of past infection with HBV in members of the West Yorkshire Fire Service. Sera from 173 firemen, 9·3% of the brigade, were tested for antibodies to HBV surface antigen and to core antigen. Those containing anti-HBs≥10 IU/L or anti-core antibody, were also tested for antibody to HBe antigen. The presence of more than one marker was used to define past infection. One sample satisfied this criterion, giving a prevalence rate of 0·6%. This compares with a rate of 1% in London blood donors. We conclude that the group shows no evidence of having been at increased risk of HBV infection. A comprehensive vaccination policy for firemen might be questionable
Salmonella enteritidis phage type 4 from the contents of intact eggs: a study involving naturally infected hens
Authors: Humphrey T. J. , Baskerville A. , Mawer S. , Rowe B. , Hopper S.
Published: May 2009

Two small flocks of egg-laying hens, naturally infected with Salmonella enteritidis. were housed in individual cages so that their eggs could be identified. During a longitudinal study where the contents of 1119 eggs were examined, 11 were positive for S. enteritidis. One isolate was phage type (PT) 33 the others were PT4. The production of infected eggs was clustered though intermittent. The positive eggs. which were produced by 10 of the 35 hens, were all found to contain fewer than 10 salmonellas. Some birds were also apparently carrying S. hadar PT14 as this organism was isolated from the contents of six Cracked eggs.
The effect of pre-enrichment on recovery ofStreptococcus agalactiae, Staphylococcus aureusand mycoplasma from bovine milk
Authors: Thurmond M. C. , Tyler J. W. , Luiz D. M. , Holmberg C. A. , Picanso J. P.
Published: May 2009

The study was conducted to determine whether pre-enrichment would increase sensitivity of detectingStreptococcus (Str.) aqalactiae, Staphylococcus (S.) aureus, and mycoplasma in bovine milk. Two procedures were followed, one involving direct inoculation of milk on bovine blood agar, and the other involving preenrichment in broth followed by inoculation on agar. Logistic regression was used to predict the probability of isolation as a function of culture procedure and two additional covariates. the California Mastitis Test (CMT) score of the milk and the type of sample (indicating sample storage temperature and herd mastitis status). A total of 13778 milk samples was cultured for each of the three bacteria. By using results of both direct inoculation and pre-enrichment, the probability of isolation compared to use of direct inoculation only and adjusted for effects of other variables was increased 3·6-fold forStr. agalactiae, 1·6-fold forS. aureusand 1·7- fold for mycoplasma. The probability of isolation for all three bacteria increased as the CMT score increased. ForStr. agalactiae, there was a statistical interaction predicting that enrichment improved the odds of isolation more from milk with high CMT scores than from milk with low scores. Results indicate that preenrichment can substantially increase the sensitivity of bacteriological screening of dairy cows for mastitis caused byStr. agalactiae,S. aureus, and mycoplasma.
Laboratory diagnosis ofMycoplasma pneumoniaeinfection: 3. Detection of IgM antibodies toM. pneumoniaeby a modified indirect haemagglutination test
Authors: Kok T.-W. , Marmion B. P. , Varkanis G. , Worswick D. A. , Martin J.
Published: May 2009

The indirect haemagglutination (IHA) test was compared with the complement-fixation (CF) test for the measurement of antibodies toMycoplasma pneumoniae. A modification of the IHA was used to measureM. pneumoniaeIgM antibodies. Sera were obtained from various groups of patients who were either culture or antigen positive forM. pneumoniaein nasopharyngeal aspirates or who had fourfold or greater increase in CF antibody or a titre ≥ 320.
Drug-resistant coagulase-negative skin staphylococci: Evaluation of four marker systems and epidemiology in an orthopaedic ward
Authors: Thore M. , Kühn I. , Löfdahl S. , Burman L. G.
Published: May 2009

Drug-resistant coagulase-negative staphylococci (DRCNS) in orthopaedic patients and ward staff were studied. A significant increase in the DRCNS carriage rate was observed among the 16 patients studied after 14 days of hospitalization with levels approaching that of the staff. Patients receiving dicloxacillin prophylaxis (n=9) were more likely to be colonized with methicillin-resistant CNS, while patients receiving no antibiotics (n= 7) became to a larger extent colonized with multiple DRCNS. The combined data from species determination, biochemical, plasmid, and antibiogram typing revealed a considerable diversity among DRCNS;64 types were distinguished among 112 DRCNS isolates selected for study after exclusion of apparently duplicate isolates. Plasmid plus antibiogram typing yielded almost as many types (61); whereas species determination plus antibiogram distinguished only 33 types. Although a novel computerized 96-reaction boityping method alone enabled differentiation of 17 biotypes, most DRCNS isolates belonged to one of three major biotypes limiting the usefulness of this method. Ten of the 64 (16%) DRCNS types identified comprised 50 of the 112 (45%) isolates. These were isolated from staff and from patients on day 14, suggesting a nosocomial origin.
Sex differentials in susceptibility to lymphatic filariasis and implications for maternal child immunity
Authors: Brabin L.
Published: May 2009

This paper reviews epidemiological data to see if there are sex differentials in prevalence, density and clinical pathology due to lymphatic filariasis. Of 53 studies from Africa, South East Asia, the Indian Subcontinent and The Americas, 43 showed a lower mean prevalence of infection in females than in males. Prevalence is consistently lower in women of reproductive age and this is statistically significant in 16 of 32 studies classified by age and sex. Density of infection is also lower in the reproductive age but may be higher in children and in older women. Clinical disease is also lower in women and pathology has a later age of onset and rise to peak prevalence than in males. The paper assesses the evidence that lower rates of infection and clinical pathology are due to less exposure of females to infective vectors. It seems unlikely that exposure alone could account for these differences which are observed for both bancroftian and brugian filariasis, irrespective of periodicity. Several investigators have suggested that females have increased resistance to infection and this is supported by serological studies showing high antibody positivity to adult worm antigens in females. The review concludes that the association with the reproductive years suggests a pregnancy-associated mechanism. This has important implications for maternal – fetal interactions and maternal filarial infection may influence the development of immunity in children.
Evaluation of numerical typing systems forEscherichia coliusing the API 50 CH and the PhP-EC systems as models
Authors: Kühn I. , Brauner A. , Möllby R.
Published: May 2009

Reproducible and discriminating typing methods are required for epidemio-logical investigations. Numerical typing systems analyse patterns obtained in various ways by calculating similarity coefficients between isolates. In the present study, various measures of the efficiency of a numerical typing system are quantified. These include reproducibility, accuracy, and discrimination power.

Three different numerical typing methods forEscherichia coliwere compared using these measures: (a) Biotyping with API 50 CH system, (b) Biochemical fingerprinting with the API 50 CH system and (c) Biochemical fingerprinting with the PhP-EC system. Biotyping qualitatively measures the results of a set of biochemical reactions as + or −. Biochemical fingerprinting also uses biochemical reactions, but the tests are scored quantitatively by measuring the kinetics and intensity of each reaction.

It was found that biotyping yielded poor reproducibility. When biochemical fingerprinting analysis was used with the API 50 CHE system the reproducibility and the discrimination was good. The PhP-EC system for biochemical fingerprinting showed equal reproducibility but was superior to the API 50 CH system with regard to discrimination power.
Serological typing of coagulase-negative staphylococci using monoclonal antibodies
Authors: Gabelish C. , Harbour C. , Beard-Pegler M. A. , Stubbs E. , Steffe R. , Large M. , Vickery A. , Benn R.
Published: May 2009

This investigation was to determine whether monoclonal antibodies (Mabs) could be used to differentiate coagulase-negative staphylococci (C-NS) at species and strain level. Mabs were produced to fourStaphylococcus epidermidisstrains, twoS. haemolyticusstrains, oneS. saprophyticusstrain and oneS. warneristrain. A panel of nine antibodies was tested for species and strain specificity against five type strains and 65 clinical isolates of C-NS by enzyme-linked immunosorbent assay (ELISA). Species specificity was found with Mab D150 produced to oneS. haemolyticusstrain. Using Mab D150 and Mab D198 in conjunction, identification of 90% ofS. haemolyticusisolates to species level was achieved.S. saprophyticusMab K84 reacted with most other strains of C-NS tested but only threeS. haemolyticusstrains (16%). This finding provides further evidence thatS. haemolyticuspossesses different surface determinants to other C-NS which could form the basis of a typing scheme forS. haemolyticususing Mabs D150, D198 and K84.
Congenital Cataract Following German Measles in the Mother
Authors: Gregg N. McAlister
Published: May 2009

IN the first half of the year, 1941, an unusual number of cases of congenital cataract made their appearance in Sydney. Cases of similar type, which appeared during the same period, have since been reported from widely separated parts of Australia. Their frequency, unusual characteristics and wide distribution warranted closer investigation, and this report is an attempt to bring to notice some of the more important features of what might almost be regarded as a mild epidemic.
Civil war and the spread of AIDS in Central Africa
Authors: Smallman-Raynor M. R. , Cliff A. D.
Published: May 2009

Using ordinary least squares regression techniques this paper demonstrates, for the first time, that the classic association of war and disease substantially accounts for the presently observed geographical distribution of reported clinical AIDS cases in Uganda. Both the spread of HIV 1 infection in the 1980s, and the subsequent development of AIDS to its 1990 spatial pattern, are shown to be significantly and positively correlated with ethnic patterns of recruitment into the Ugandan National Liberation Army (UNLA) after the overthrow of Idi Amin some 10 years earlier in 1979. This correlation reflects the estimated mean incubation period of 8–10 years for HIV 1 and underlines the need for cognizance of historical factors which may have influenced current patterns of AIDS seen in Central Africa. The findings may have important implications for AIDS forecasting and control in African countries which have recently experienced war. The results are compared with parallel analyses of other HIV hypotheses advanced to account for the reported geographical distribution of AIDS in Uganda.
A longitudinal study of natural infection of piglets with Streptococcus suis types 1 and 2
Authors: Robertson I. D. , Blackmore D. K. , Hampson D. J. , Fu Z. F.
Published: May 2009

Streptococcus suis types 1 and 2 were detected in nasal swabs taken from five litters of piglets sampled twice weekly from birth. The two types had been detected in all pigs by the time they were 38 and 25 days old respectively with mean ages of first detectable infection being 13·5 and 8·5 days. The prevalence of infection was not affected by housing conditions or the population density of pigs. Piglets originating from a sow with vaginal swabs positive for S. suis type 2 were infected earlier than piglets from non-vaginal carriers. It is concluded that infection of piglets with S. suis type 2 may occur during the birth process.
An outbreak of Legionnaires' disease in Gloucester
Authors: Hunt D. A. , Cartwright K. A. V. , Smith M. C. , Middleton J. , Bartlett C. L. R. , Lee J. V. , Dennis P. J. , Harper D.
Published: May 2009

Fourteen people living in or near the city of Gloucester fell ill with Legionnaires' disease caused by Legionella pneumophila serogroup (SG) 1 between 27 August and 27 October 1986. Another patient had fallen ill on 30 May. Nine of the 15 were diagnosed retrospectively during a case finding exercise. There were three deaths. Three cases of Pontiac fever were also diagnosed.

The source was probably one or more wet cooling towers. Nineteen premises in the city with such towers were identified, and three just outside Gloucester. Samples from 11 of the 22 premises grew Legionella spp.; from nine of these L. pneumophila SG 1 (Pontiac) was isolated. The efficacy of regular addition of biocide in addition to hypochlorite added at the time of disinfection in inhibiting the growth of Legionella spp. was demonstrated.

A survey of patients' movements during their likely incubation period showed that there was no single building that all patients had visited, but there were two areas of the city which nearly all had visited or passed through by car. A case-control study demonstrated an association with one of these areas.

Cooling towers near both areas may have been sources but the evidence is insufficient to incriminate any single one. The unexpected finding of L. pneumophila SG 1 (Pontiac) in nine towers supports the hypothesis that there may have been multiple sources. Cooling towers may have been contaminated by mains water or by drift from other towers.
Physical protection against airborne pathogens and pollutants by a novel animal isolator in a level 3 containment laboratory
Authors: Wathes C. M. , Johnson H. E.
Published: May 2009

A containment laboratory unit for research with aerosols of group 2 pathogenic microorganisms is described. The design criteria are based on current UK guidelines, which imply containment at group 3 level during aerosol production, storage, exposure of animals and sampling. Within the aerosol laboratory, primary containment is provided by a Henderson apparatus operating at a negative pressure to the external environment. Flexible film isolators under negative pressure are used for all hazardous microbiological work, e.g. tissue homogenization, and for housing infected laboratory rodents. A novel feature of the animal isolator is the separate ventilation of each cage, which minimizes the risk of cross-infection by aerosol transmission and ensures a similar environment within each cage. The results of an intentional release of a cloud of non-pathogenic microorganisms are presented to show the effectiveness of the containment barriers. Recommendations are given for the safe operation of a containment unit based upon practical experience.
An outbreak of cryptosporidiosis associated with a swimming pool
Authors: Joce R. E. , Bruce J. , Kiely D. , Noah N. D. , Dempster W. B. , Stalker R. , Gumsley P. , Chapman P. A. , Norman P. , Watkins J. , Smith H. V. , Price T. J. , Watts D.
Published: May 2009

In August 1988 an increase was noted in the number of cases of cryptosporidiosis identified by the microbiology laboratory at Doncaster Royal Infirmary. By 31 October, 67 cases had been reported. Preliminary investigations implicated the use of one of two swimming pools at a local sports centre and oocysts were identified in the pool water. Inspection of the pool revealed significant plumbing defects which had allowed ingress of sewage from the main sewer into the circulating pool water. Epidemiological investigation confirmed an association between head immersion and illness. The pools were closed when oocysts were identified in the water and extensive cleaning and repair work was undertaken. The pool water was retested for cryptosporidial oocysts and found to be negative before the pool re-opened.
Genotypic and phenotypic analysis ofStreptococcus uberisisolated from bovine mammary secretions
Authors: Jayarao B. M. , Oliver S. P. , Tagg J. R. , Matthews K. R.
Published: May 2009

Genotypic and phenotypic analysis of 42 strains ofStreptococcus uberisisolated from mammary secretions of 17 cows collected at different periods of the lactation cycle and from episodes of clinical mastitis were performed. Seventeen restriction endonuclease fingerprint (REF) patterns and 12 bacteriocin-like inhibitory substance (BLIS) fingerprints were observed. REF identified and differentiated closely related strains ofS. uberisisolated from mammary secretions collected from the same cow at different periods of the lactation cycle and from episodes of clinical mastitis. BLIS fingerprinting ofS. uberiscomplemented REF results. REF and BLIS fingerprinting provided evidence concerning persistence of infection in the same quarter or different quarters of the mammary gland over different periods of the lactation cycle, and occurrence of infection with similar and dissimilar strains ofS. uberis. Biochemical profiles could not identify closely related strains nor did they complement REF results. Antibiotic resistance patterns alone were of little value in differentiating closely related strains, but were identical with isolates having same REF pattern. None of theS. uberisstrains was found to carry plasmids. REF and BLIS fingerprinting can be utilized effectively to differentiate closely related and unrelated strains ofS. uberisisolated from bovine mammary secretions.
Differentiation of strains ofHelicobacter pyloriby numerical analysis of 1-D SDS-PAGE protein patterns: Evidence for post-treatment recrudescence
Authors: Costas M. , Morgan D. D. , Owen R. J. , Morgan D. R.
Published: May 2009

Twenty-three pre- and post-treatment isolates ofHelicobacter pylorifrom the antral mucosa of eight patients with dyspepsia and gastritis were compared using 1-D SDS PAGE of proteins. The protein patterns were highly reproducible and were used as the basis for two numerical analyses. The first, based on the total protein patterns, showed that a number of the strains did not cluster with their respective patient set. This was thought to be due to differences in both mobility and intensity of proteins in the major band region. The second analysis, based on partial patterns, excluding the major band region (51–68 kDa), divided the clinical isolates into clearly defined groups corresponding to the patient sets. Although there was a degree of heterogeneity with respect to protein pattern between the pre- and post-treatment isolates of some patients, there was nonetheless clear evidence that each patient was harbouring strains of only a single type. These results suggested that patients were not being reinfected with a different strain but that there was recrudescence of the pre-treatment strain. Protein ‘fingerprints’ provided a precise and reproducible means of strain differentiation, and revealed that in each patient the same strain persisted after drug therapy even though there was marked patient-to-patient strain variation.
Relapse versus reinfection withClostridium difficile
Authors: O'Neill G. L. , Beaman M. H. , Riley T. V.
Published: May 2009

Relapse ofClostridium, difficile-associated diarrhoea occurs in 15–20% of patients; however, whether relapse is due to an endogenous source of the organism or reinfection from the environment remains unclear. Restriction enzyme analysis (REA) of chromosomal DNA was used to type multiple isolates from ten patients who had experienced apparent relapses. More than half the relapses were due to infection with a new strain ofC. difficile. The remaining patients were infected with the same strain, but whether this strain was acquired from the environment or from endogenous sources could not be determined. Relapses with a different strain ofC. difficilecould occur if an individual harboured more than one strain in their gastrointestinal tract. To investigate this possibility ten other patients were assessed for carriage of multiple strains. Ten colonies from a primary culture plate from each patient were typed by REA and tested for their ability to produce cytotoxin. All isolates from the same patient were identical by both methods, indicating that multiple carriage of strains may be a rare event.
Drug resistance and plasmid profile of shigellae in Taiwan
Authors: Lin S.-R. , Chang S.-F.
Published: May 2009

One hundred and twenty-eight shigella strains isolated from newborn and infant human faecal specimens at Kaohsiung Medical College Hospital in Taiwan were serogrouped, serotyped and examined for drug-resistance patterns and for the presence of plasmids. Forty-seven pre cent of the isolates were found to belong to theShigella sonneiserogroup, 41%to theS.flexnerigroup,9%to theS.boydiigroup and 3%to theS.dysenteriaegroup.The serotype with the greatest number of strains wasS.sonneiI. (29 %) followed byS. flexneri1 (27%). Each strain was tested for resistance to 11 antimicrobial agents. Eighty-eight per cent of the strains were resistant to tetracycline, 87% to chloramphenicol, 84% to streptomycin, 52% to ampicillin, 25% to nalidixic acid, 29% to kanamycin, 11 % to cephalothin, 11% to neomycin, 10% to cotrimoxazole, 1% to amikacin and none to gentamicin. The most prevalent resistance pattern was ApCmSmTc (28%). Clinical isolates demonstrating multiple resistance were found to harbour a large transmissible plasmid of 45–75 MDa while isolates without multiple resistance did not. Two large virulence plasmids of 123 and 110 MDa were found in 12 strains ofS. flexneriand 4 strains ofS. sonneiphase I. Small plasmids of 4·5, 4·2, 3·5, 2·8, 2·5. 2·0 and 1·5 MDa were also present in all strains. These small plasmids were species specific and can be used as marker plasmids to identify species.
The epidemiology ofSarcocystisspp. in cattle of Western Australia
Authors: Savini G. , Dunsmore J. D. , Robertson I. D. , Seneviratna P.
Published: May 2009

Oesophagus samples from 714 cattle from Western Australia were examined by artificial digestion to detect the presence ofSarcocystisspp. The overall prevalence of infection was 52%. The prevalence of infection increased with age and was highest in the entire males (92%). The prevalence was lower in cattle which originated from arid and semiarid regions (9 and 31% respectively) than those from tropical (87%) and temperate (60%) regions. possible reasons for these differences are discussed and it is concluded that environmental and management factors as well as host age and sex influence the prevalence of infection withSarcocystisspp. in cattle.
Rotavirus detection by dot blot hybridization assay using a non-radioactive synthetic oligodeoxynucleotide probe
Authors: Fernández J. , Sandino A. , Yudelevich A. , Avendaño L. F. , Venegas A. , Hinrichsen V. , Spencer E.
Published: May 2009

A synthetic oligodeoxynucletide of 40 nucleotides corresponding to nucleotides 33–72 of the gene coding for the viral protein VP7 of rotavirus, was used as a nucleic acid probe to develop a non-radiactive hybridization method for rotavirus detection. The probe was labelled at the 3' end with biotin-7-dATP. The sensitivity and specificity of the dot blot hybridization assay for rotavirus detection was evaluated with 303 stool specimens. The results indicate that the hybridization assay has a higher sensitivity than both PAGE and EIA. Among the rotavirus strains tested 37 different electropherotypes were found. The results suggest that rotavirus diagnosis by dot hybridization using a non-radioactive probe may become routine laboratory procedure because it is simple, highly specific and very sensitive.
The detection of African horse sickness virus antigens and antibodies in young equidae
Authors: Hamblin C. , Anderson E. C. , Mellor P. S. , Graham S. D. , Mertens P. P. C. , Burroughs J. N.
Published: May 2009

Four ponies were each inoculated with a different serotype of African horse sickness virus (AHSV) which had been passaged through cell culture in order to achieve attenuation. Three of the ponies died suddenly after showing mild clinical signs, the fourth pony remained clinically normal and was killed at day 38. Infectious AHSV was isolated from blood samples collected at intervals from all four ponies. Positive antigen ELISA reactions were only observed with blood samples from two of the ponies on the two days preceding death. Specific AHSV antibodies were detected by ELISA in serum samples from the other two ponies although one eventually died. African horse sickness viral antigens were detected by ELISA in post-mortem tissue samples collected from all four ponies. No infectious virus could be detected in tissue samples taken post-mortem from the pony which survived African horse sickness (AHS) infection. In the event of a suspected outbreak of AHS it is recommended that sera and heparinized blood should be tested for specific antibodies and AHSV antigen respectively. When available, post-mortem tissues, including spleen, heart, lung and liver, should also be tested for AHSV antigen. Although the ELISA used for the detection of AHSV antigen is highly sensitive and specific, negative ELISA results should be confirmed by virus isolation attempts.
An epidemic methicillin-resistant strain of Staphylococcus aureus in Spain
Authors: Aparicio P. , Richardson J. , Martin S. , Vindel A. , Marples R. R. , Cookson B. D.
Published: May 2009

During 1990, a strain of methicillin-resistant Staphylococcus aureus became epidemic in Spain and spread in a manner analogous to that of EMRSA-1 in England. Isolates of this strain produced little protein A and were resistant to a number of antibiotics including ciprofloxacin. Beta-lactamase production was encoded by a c. 39 kb plasmid, which also conferred resistance to mercury, cadmium, ethidium bromide and propamidine isethionate.

Investigation showed that two variants, separable by supplementary and Fisk phage typing, were circulating. The B variant appeared to spread more readily than the A variant.

The opportunity was taken to compare the discriminatory power of traditional typing methods with molecular techniques. The discriminatory power of the molecular techniques used only reached the same level as the traditional methods when double enzyme digestion of total cellular DNA by EcoR I and Cla I was performed.
Isolation of an agent of the spotted fever group rickettsia from tick eggs in Madrid, Spain
Authors: Herrero C. , Pelaz C. , Martín-Bourgon C.
Published: May 2009

Ticks recovered from dogs in rural villages around Madrid (Spain) were processed to isolate rickettsiae. One sample containing mixtures of ticks and four containing eggs, in which rickettsiae had been detected by indirect immunofluorescence with a human serum highly reactive toRickettsia conorii, were decontaminated, homogenized and inoculated onto Vero cells. Two egg samples yielded a cytopathic agent that reacted positively by immunofluorescence. One sample (14H) was successfully subcultured and identified as a member of the spotted fever group rickettsia. Tick eggs provide suitable material for isolation of rickettsia.
A one-year study of streptococcal infections and their complications among Ethiopian children
Authors: Tewodros W. , Muhe L. , Daniel E. , Schalén C. , Kronvall G.
Published: May 2009

Post-streptococcal complications are known to be common among Ethiopian children. Little is known, however, about the epidemiology of beta-haemolytic streptococci in Ethiopia. A total of 816 children were studied during a one-year period: 24 cases of acute rheumatic fever (ARF), 44 chronic rheumatic heart disease (CRHD), 44 acute post streptococcal glomerulonephritis (APSGN), 143 tonsillitis, 55 impetigo, and 506 were apparently healthy children. Both ARF and APSGN occurred throughout the year with two peaks during the rainy and cold seasons. The female: male ratio among ARF patients was 1·4:1 and 1:1·9 among APSGN. The monthly carrier rate of beta-haemolytic streptococci group A varied from 7·5–39%, average being 17%. T type 2 was the most frequent serotype. Marked seasonal fluctuations were noted in the distribution of serogroups among apparently healthy children. Beta-haemolytic streptococci group A dominated during the hot and humid months of February–May. Strains were susceptible to commonly used antibiotics, except for tetracycline.
A study of phenotypic variation ofStaphylococcus epidermidisusing Congo red agar
Authors: Deighton M. A. , Capstick J. , Borland R.
Published: May 2009

This study examines a series of phenotypic variants ofStaphylococcus epidermidisthat were generated from a pair of parent variants, isolated from valvular tissue of a patient with prosthetic valve endocarditis. The variants were initially classified by examining their colonial morphology on Congo red agar. In addition to differences in Congo red binding and colonial morphology, they differed in the expression of several surface components and enzymes. Despite these phenotypic differences, all variants had the same restriction endonuclease profile of plasmid DNA. Examination of a collection of clinical isolates demonstrated that phenotypic variation is a common property ofS. epidermidis. The ability to express different combinations of surface components and enzymes could contribute to the virulence ofS. epidermidisstrains by enabling these organisms to colonize a range of diverse environments.
A longitudinal study ofStaphylococcus hyicuscolonization of vagina of gilts and transmission to piglets
Authors: Wegener H. C. , Skov-Jensen E. W.
Published: May 2009

HighStaphylococcus hyicuscolonization rates were found in vaginal samples of healthy breeding sows and in skin samples of their offspring. Twenty-two different phage types were identified among the 720 isolates ofS. hyicusexamined. Two to 13 different phage types were isolated per herd. Phage typing, as well as characterization of about 10% of the isolates by plasmid profiles and antibiogram patterns, showed that, several different clones ofS. hyicuscould be present simultaneously in vagina of gilts and also on skin of piglets. Generally isolates from the vagina of one animal were identical as regards to phage types, plasmid profiles, and antibiogram patterns during the entire investigation period. Isolates from the skin of piglets were of the same type as their mothers, indicating that vertical transmission had taken place.S. hyicusstrains isolated from the skin of piglets within 24 h after birth were identical to strains isolated 3 weeks after birth from the same litter, indicating that the vaginal strains became part of a stable skin flora.
Factors influencing oral carriage of yeasts among individuals with diabetes mellitus
Authors: Aly F. Z. , Blackwell C. C. , Mackenzie D. A. C. , Weir D. M. , Clarke B. F.
Published: May 2009

A total of 439 individuals with diabetes mellitus were examined for carriage of yeasts by the oral rinse and palatal swab techniques. Eighteen genetic or environment variables were assessed for their contribution to carriage of yeasts. The factor contributing to palatal and oral carriage of yeasts among individuals with insulin dependent diabetes mellitus (IDDM) was age (P < 0·01). The factor contributing to palatal carriage of yeasts among individuals with non-insulin dependent diabetes mellitus (NIDDM) was poor glycaemic control (glycosuria P < 0·01); carriage in the oral cavity as a whole was influenced additionally by non-secretion of ABH blood group antigens (P < 0·05). Introduction of a denture altered the above risk factors. For individuals with IDDM, oral carriage was associated with the presence of retinopathy (P < 0·05); palatal carriage was influenced by poor glycaemic control (HbA1P < 0·01, plasma glucose levels P < 0·05) and age (P < 0·05). For those with NIDDM, palatal carriage was associated with continuous presence of the denture in the mouth (P < 0·01); oral carriage was associated with plasma glucose levels (P < 0·05).
Comparison of the HA genes of type B influenza viruses in herald waves and later epidemic seasons
Authors: Nakajima S. , Nishikawa F. , Nakamura K. , Nakajima K.
Published: May 2009

From January 1985 to May 1991, herald strains of influenza B virus were isolated in 1987 and 1989 in Japan. In both cases, influenza epidemics caused by the same type followed in the next winter season. The HA gene sequences of the influenza B viruses isolated in Japan from 1987–91, which covers two herald waves of influenza B viruses, were analysed and located on the phylogenetic tree for influenza B viruses after the B/Singapore/64 strain. Co-circulation of at least two evolutionary lineages of the HA genes existed for influenza B viruses in Japan during the period of this study. The herald viruses in one wave (1987) were genetically close to the winter isolates and were considered to be the parental viruses for the following influenza season, while in the other wave (1989) winter isolates belonged to another lineage on which one of the herald viruses was located, but they were genetically and antigenically different from the herald viruses.
A large salmonellosis outbreak associated with a frequently penalized restaurant
Authors: Luby S. P. , Jones J. L. , Horan J. M.
Published: May 2009

Between January and June 1990, Restaurant A in Greenville, South Carolina repeatedly failed local health department inspection and was repeatedly sanctioned. In September 1990, two persons, hospitalized with salmonellosis after attending a convention catered by Restaurant A, contacted the South Carolina Department of Health and Environmental Control. We inspected Restaurant A, interviewed food handlers, and surveyed by telephone persons from every sixth business attending the convention. Of 398 persons interviewed, 135 (34%) reported gastroenteritis. Nine had culture-confirmed salmonella infection. People who ate turkey were 4.6 times more likely to become ill than those who did not eat turkey (95% confidence interval 2.0, 10.6). We estimate that of 2430 attendees, 824 became ill. Sanitarians judged Restaurant A's kitchen too small to prepare over 500 meals safely. The cooked turkey was unrefrigerated for several hours, incompletely rewarmed, and rinsed with water to reduce its offensive odour prior to serving. Stronger sanctions may be needed against restaurants that repeatedly fail local health department inspection.
Iron restriction and the growth ofSalmonella enteritidis
Authors: Chart H. , Rowe B.
Published: May 2009

Strains ofSalmonella enteritidiswere examined for their ability to remove ferricions from the iron chelating agents ovotransferrin, Desferal and EDDA. Growth ofS. enteritidisphage type (PT) 4 (SE4) in trypticase soy broth containing ovotransferrin resulted in the expression of iron regulated outer membrane proteins (OMPs) of 74. 78 and 81 kDa. and unexpectedly the repression of expression of OMP C. The 38 MDa ‘mouse virulence’ plasmid was not required for the expression of the iron-regulated OMPs (IROMPs). SE4 was able to obtain iron bound to the iron chelator Desferal and EDDA without expressing a high-affinity iron uptake system. Strains ofS. enteritidisbelonging to PTs 7. 8, 13a, 23. 24 and 30 were also able to remove ferric ions from Desferal and EDDA without expressing a high-affinity iron uptake system. We conclude that strains of SE4 possess a high-affinity iron sequestering mechanism that can readily remove iron from ovotransferrin. It is likely that iron limitation, and not iron restriction, is responsible for the bacteriostatic properties of fresh egg whites.
Crystal violet reactions ofStaphylococcus aureusstrains colonizing infants in the first six weeks
Authors: Hudson S. J. , Freeman R. , Burdess D. , Cookson B. D.
Published: May 2009

Nasal colonization withStaphylococcus aureusoccurred in 18% of babies leaving a maternity unit and had risen to 40% by 6 weeks after birth.S. aureuswas first acquired by 34·5% of babies after discharge. Female infants were more likely to be colonized than males. Colonization was not significantly different between babies receiving standard postnatal care and those nursed on the Special Care Baby Unit.

Crystal violet (CV) tests showed that purple-reacting isolates accounted for approximately 60% of strains, whether first detected at hospital discharge or subsequently acquired. Purple-reacting strains, once acquired, were significantly better able to persist than non purple-reacting strains and formed a cumulatively higher proportion of the strains isolated at 6 weeks after birth than at hospital discharge. CV purple-reactions were significantly associated with lysis by phages of groups III and I and non-purple-reactions were significantly associated with lysis by phages of group II and/or 94/96.

Maternity units remain a significant route whereby strains ofS. aureuswith some characteristics associated with a hospital origin gain access to the community.
Detection ofCowdria ruminantiumby means of a DNA probe, pCS20 in infected bont ticks,Amblyomma hebraeum, the major vector of heartwater in Southern Africa
Authors: Yunker C. E. , Mahan S. M. , Waghela S. D , McGuire T. C. , Rurangirwa F. R. , Barbet A. F. , Wassink L. A.
Published: May 2009

A DNA probe, pCS20, previously described for use in detection ofCowdria ruminantiuminfections inAmblyomma variegatum(the principal vector of heartwater) hybridized withC. ruminantiumDNA in organs of laboratory-infectedA. hebraeumadult ticks (the major southern African vector of heartwater). The probe hybridized withC. ruminantiumDNA in 46/49 midguts from male ticks and 26/29 from females, thus indicating infection. Corresponding salivary glands were less heavily infected, but infections were more numerous in glands from males. Infection in ticks was confirmed by transmission of the disease to susceptible goats. The probe did not hybridize with DNA from uninfected ticks or with DNA from a spotted fever group rickettsia commonly associated withA. hebraeumin Zimbabwe. TheC. ruminantiumspecific pCS20 DNA probe can be applied to determine accurately the infection rates in the two major vectors of heartwater and the risk of exposure of ruminants in endemic areas.
Occurrence of oocysts ofCryptosporidiumsp. inLarusspp. gulls
Authors: Smith H. V. , Brown J. , Coulson J. C. , Morris G. P. , Girdwood R. W. A.
Published: May 2009

Between November 1990 and February 1991 101 gull faecal samples, collected in central Scotland, and 50 cloacal lavages, from gulls captured at two refuse tips near Durham, England were examined for the presence ofCryptosporidiumsp. oocysts. Five of 101 (c 5%) of faecal samples and 11 of 50 (22%) of cloacal lavages contained oocysts, of which 64% and 83%, respectively were considered viable when examined with propidium iodide and 4′-6-diamidino-2-phenylindole. Since there is insufficient evidence to ascribe these oocysts to a recognized species they are therefore referred to asCryptosporidiumsp. oocysts. There were significant differences in the occurrence of oocysts between gulls captured at the different refuse tips (P < 0.01), but no significant difference between the distribution of oocysts in two species of gull,Larus argentatus(Herring Gull) andL. ridibundus(Black-head Gull). The differences may be explained by different food sources and feeding habits. The contribution of gulls to environmental contamination withCryptosporidiumsp. oocysts is probably generally small, but may be more significant when large numbers roost on surface waters.
Pathogenicity ofFusobacterium necrophorumstrains from man and animals
Authors: Smith G. R. , Thornton E. A.
Published: May 2009

Necrobacillosis occurs in man and animals. The typical forms of the disease in animals are caused byFusobacterium necrophorumbiovar A; biovar B strains are much less pathogenic. In this study the pathogenicity for mice of eight human isolates ofF. necrophorumwas compared with that of animal biovar A and B strains.

By subcutaneous inoculation seven of the human strains differed from biovar A but resembled biovar B in (1) producing, at the most, mild local lesions that rapidly healed, and (2) showing no enhancement of infectivity when suspended in sub-lethal doses ofStaphylococcus aureusbroth culture. The eighth human strain (A2433) resembled biovar A but differed from biovar B in (1) producing severe lesions, and (2) showing greatly enhanced infectivity in the presence ofS. aureus. Nonetheless, strain A2433 differed from biovar A, both in the nature of the lesions produced and in its failure to cause severe general signs of illness and rapidly fatal infection.

By intravenous inoculation one of two biovar B strains and all except one of the eight human strains produced purulent lesions, often severe, in the liver and elsewhere, but infection was not usually associated with general signs of illness. In contrast, intravenous injection of a biovar A strain gave rise to a rapidly fatal infection, with severe lesions in the liver or elsewhere.

The results suggest that the term ‘necrobacillosis’ as used in human and veterinary medicine refers to diseases that differ in important respects.
Occurrence ofGiardiasp. cysts andCryptosporidiumsp. oocysts in faeces from public parks in the west of Scotland
Authors: Grimason A. M. , Smith* H. V. , Parker J. F. W. , Jackson M. H. , Smith P. G. , Girdwood R. W. A.
Published: May 2009

One hundred faecal specimens, randomly collected from various locations within seven public parks in the west of Scotland, were examined for the presence ofGiardiasp. cysts andCryptosporidiumsp. oocysts. Eleven percent of samples containedGiardiasp. cysts and 1 % containedCryptosporidiumsp. oocysts. Occurrence data from individual parks varied from 0 to 40% forGiardiaand 0 to 2.4% forCryptosporidium. The occurrence of parasitic organisms in public parks, especially in the vicinity of children’s playing areas is a matter of concern for public health officials and regulators of leisure and recreation amenities.
Clostridium difficile-associated diarrhoea: epidemiological data from Western Australia
Authors: Riley T. V. , O'Neill G. L. , Bowman R. A. , Golledge C. L.
Published: May 2009

The incidence ofClostridium difficile-associated diarrhoea (CDAD) was investigated retrospectively at a 690-bed teaching hospital for the period 1983–92. Our aims were to determine: (i) the distribution by age and sex of patients with CDAD, (ii) the possibility of a seasonal trend and, (iii) the influence of infection control procedures, contamination of the hospital environment and the use of third-generation cephalosporins. The laboratory diagnosis of CDAD was based on demonstration of the organism by stool culture and/or detection of specific cytotoxin in stool filtrates.C. difficilewas detected in 917 patients who were being investigated for diarrhoeal illness. Yearly isolations varied from a low of 49 in 1983 to a high of 120 in 1990 (Chi square for linear trend 128·8;P <0·005). Most patients were elderly, with 63% aged 60 years or more; the majority (59%) were female. The relationship between culture ofC. difficileand detection of cytotoxin in faecal extracts was also examined. Sixty percent of a sample of 132 isolates from patients in whom faecal cytotoxin was not detected produced cytotoxinin vitro, suggesting that culture is a more sensitive indicator of infection withC. difficilethan cytotoxin detection. When the total number of faecal specimens received in the laboratory was used as a denominator there was an increase in the number of incident cases of CDAD between 1983 and 1990, apart from 1986. When occupied bed days was used as the denominator a similar trend was observed with a peak in 1990. These increases correlated with an increase in the use of third-generation cephalosporins at SCGH between 1983 and 1989 (Pearson's correlation coefficient, 0·90). The introduction of Body Substance Isolation in 1989, in conjunction with other infection control procedures, appears to have halted the rise, despite a continuing use of broad-spectrum cephalosporins. In order to reduce the number of cases of CDAD, either a reduction in levels of environmental contamination or a reduction in the use of third-generation cephalosporins is required. If this can be achieved the economic consequences, in terms of an opportunity cost, will be considerable.
Reinfection with influenza B virus in children: analysis of the reinfection influenza B viruses
Authors: Nakajima S. , Nishikawa F. , Nakamura K. , Nakao H. , Nakajima K.
Published: May 2009

Influenza B virus reinfection in Japanese children was studied epidemi-ologically during 1979–91 and virologically during 1985–91. During this investigation, there were four epidemics caused by influenza B viruses, each of which accompanied antigenic drift. Between the epidemics in 1987/88 and 1989/90, the viruses changed drastically, both genetically and antigenically. The minimum rate of reinfection with influenza B virus during the whole period was 3–25% depending on the influenza seasons. The antigens of primary and reinfection strains of influenza B virus isolated from 18 children during 1985–90, which covered three epidemic periods, were studied by haemagglutination inhibition tests. The results showed that the viruses isolated in the 1984/85 and 1987/88 influenza seasons, which belonged to the same lineage, were antigenically close, and reinfection occurred with these viruses. The results of amino-acid analysis of the HA1 polypeptide of these viruses corresponded with those of antigenic analysis. There were no specific amino-acid changes shared by the primary infection and reinfection influenza B viruses; the patients were infected with the viruses epidemic at that time.
A mathematical model of detection and dynamics of porcine transmissible gastroenteritis
Authors: Hone J.
Published: May 2009

Transmissible gastroenteritis (TGE) is a viral disease causing dehydration, diarrhoea and death in pigs. The disease is widespread in pig-producing areas of the world but does not occur in Australia. A mathematical model of TGE spread within a pig herd is proposed and calibrated by reference to published data. The model is then applied to two situations of special interest; first to estimate the delay before detection of TGE (6 to over 30 days) when infection is first introduced into a herd of domestic or feral pigs, and second the effect of the disease in a population of feral pigs (could become endemic if transmission is high).
Trimethoprim resistant dihydrofolate reductases in normal faecal flora isolated in India
Authors: Tait S. , Amyes S. G. B.
Published: May 2009

A high incidence of resistance to trimethoprim has been shown in the normal faecal flora in a population in south India. The dihydrofolate reductase (dhfr) genes mediating transferable resistance to trimethoprim have been identified. Unusually, in this study, thedhfrV was shown to be the predominant resistance gene (dhfrV 50% of tranaconjugants,dhfrIa 30%), thedhfrIb was also detected being distinguished from thedhfrV by an oligo-probe. However, when non-transferable resistance was considered, thedhfrIa was the most prevalent of thedhfrs identified. All those plasmids harbouring thedhfrIa were shown to possess Tn7. All the plasmids that probed positive for thedhfrV and thedhfrIb were shown to be associated with the integrase of the Tn21-like transposons, but 8 of thedhfrV genes were not associated with the Tn21resolvase. ThedhfrIV was shown to be present in all seven plasmids that produced low level trimethoprim-resistance. ThedhfrV. first characterized in Sri Lanka, would seem to have a local distribution in this region of Asia but is distinguishable from thedhfrIb only by the use of an oligo-probe.