bluuebunny/crossref_metadata_2025_split huggingface dataset:
Malaria transmission rates estimated from serological data
Authors: Burattini M. N. , Massad E. , Coutinho F. A. B. 
Published: May 2009

SummaryA mathematical model was used to estimate malaria transmission rates based on serological data. The model is minimally stochastic and assumes an age-dependent force of infection for malaria. The transmission rates estimated were applied to a simple compartmental model in order to mimic the malaria transmission.The model has shown a good retrieving capacity for serological and parasite prevalence data.
Polymerase chain reaction for salmonella virulence–associated plasmid genes detection: a new tool in salmonella epidemiology
Authors: Rexach L. , Dilasser F. , Fach P. 
Published: May 2009

SummaryThe important role of plasmid genes in assessing virulence for BALB/c mice in salmonella, and the difficulty of using standard techniques to detect them, led us to develop a detection method by gene amplification.One hundred and forty–three strains (71 serovars) of salmonella and 35 strains of other species were tested using specific oligonucleotide primers. The amplification products were identified by a specific oligonucleotide probe. Forty-nine salmonella strains from ten serovars (S. abortus ovis, S. choleraesuis, S. dublin, S. enteritidis, S. gallinarum / pullorum, S. hessarek, S. typhimurium, S. IIIa48:z4, z23,S. IV43: z4, z23:-,S. V28:a:-) produced a positive and specific response.Because of various origins of the strains possessing the gene sought and the diversity of the responses, both from one serovar to another and in the same serovar, this search has its place among the epidemiological markers in general use. This method appears well suited to the research and detection of plasmid genes associated with mouse virulence in salmonella.
Prospective study of verocytotoxin–producing, enteroaggregative and diffusely adherentEscherichia coliin different diarrhoeal states
Authors: Brook M. G. , Smith H. R. , Bannister B. A. , McConnell M. , Chart H. , Scotland S. M. , Sawyer A. , Smith M. , Rowe B. 
Published: May 2009

SummaryOne hundred and eighty–one stool specimens from patients with various types of diarrhoea (135 patients) or from non-diarrhoeal controls (23 acute medical patients, 23 inflammatory bowel disease in remission) were investigated using a colony–blot DNA hybridization assay for the presence of Verocytotoxin–producing (VTEC), enteroaggregative (EAggEC) and diffusely adherent (DAEC)Escherichia coli. Twelve patients had probe–positive EAggEC in the stool and 8 of these had diarrhoea, 6 following recent travel. Eight patients had DAEC, 7 of whom had travellers diarrhoea. Six of 10 (60%) travellers with gastroenteritis, but without a recognized enteric pathogen, were positive for EAggEC (4) or DAEC (2). Five of 10 (50%) travellers with gastroenteritis related to a recognized enteric pathogen also had DAEC identified in their stool. Of the 23 acute medical control patients 11 had been abroad, 4 of these were immigrants and had EAggEC. VTEC were not found and, with one exception, immunoassays for antibodies toE. coliO 157 and O 2 lipopolysaccharides were negative.
A comparison of aerosol and intragastric routes of infection withListeriaspp
Authors: Bracegirdle P. , West A. A. , Lever M. S. , Fitzgeorge R. B. , Baskerville A. 
Published: May 2009

SummaryAerosol infection (AI) of Porton outbreak mice withListeriaspecies, exhibiting varying degrees of virulence, was compared with gastric intubation (GI) on the basis of numbers of deaths. 50% lethal dose (LD50) and pattern of listerial infection. The AI route appeared to be more sensitive, efficient and consistent than GI in that it required 105fewer micro-organisms to obtain infection and death then ensued within 4 days, with GI deaths usually occurring on day 7. All the virulent strains tested caused 100% mortality by AI, while virulent and avirulent strains were indistinguishable by GI. Bacterial counts in the livers and spleens of infected mice were consistent with the relative virulence of the infectious agent using AI but not in GI mice. There were higher numbers of micro-organisms and more widespread lesions in the organs of AI mice than in GI. Results indicate that AI is an accuratein vivoindicator of virulence in listeria and using AI, bacterial counts in the liver and spleen could replace LD50tests, thereby reducing the number of animals required forin vivovirulence testing.
Patient and strain characteristics in relation to the outcome of meningococcal disease: a multivariate analysis
Authors: Scholten R. J. P. M. , Bijlmer H. A. , Valkenburg H. A. , Dankert J. 
Published: May 2009

SummaryTo investigate the joint association of patient and strain characteristics with the outcome of meningococcal disease (MD), data were collected on 563 consecutive cases of MD reported between 1989 and 1990 in The Netherlands. The meningococcal isolates were characterized with regard to their surface characteristics. Sequelae occurred in 8.5% of the patients, and were only associated with the presence of bacteraemia. The case-fatality rate was 7.7%. Infants aged ≤ 5 months and patients in the age-groups of 10–19 years and ≥ 50 years had an increased risk for a fatal outcome compared with children from 6 months to 9 years old (Odds Ratios [ORs]: 5.1, 3.4 and 9.8, respectively). The OR for females versus males was 2.3. The ORs for patients with bacteraemia, or a combination of bacteraemia and meningitis, compared with meningitic patients, were 2.3 and 3.1. Meningococcal strain characteristics did not influence the case-fatality rate substantially. In conclusion, host factors were found to be determinants for a fatal outcome of MD in The Netherlands from 1989 to 1990.
Genomic fingerprints ofStaphylococcus aureusof bovine origin by polymerase chain reaction-based DNA fingerprinting
Authors: Matthews K. R. , Kumar S. J. , O'Conner S. A. , Harmon R. J. , Pankey J. W. , Fox L. K. , Oliver S. P. 
Published: May 2009

SummaryStaphylococcus aureus(n = 75) isolated from mammary secretions of cows with subclinical and clinical mastitis from several geographic locations in the USA were examined using polymerase chain reaction-based DNA fingerprinting. DNA fingerprints were produced using a synthetic oligonucleotide primer (5‘GTAACGCC3’) to produce a distinct spectrum of amplified DNA fragments facilitating a high degree of resolution for differentiatingS. aureusstrains. PCR-based DNA fingerprinting grouped the 75S. aureusisolates into 19 distinct profiles. The technique differentiated closely related strains within and between geographic locations. Findings suggest that certain types are found across geographic regions suggesting a common clonal type. Within herd data suggest heterogeneity among subclinical and clinical isolates ofS. aureusstrains. Compared to existing typing methods, PCR-based DNA fingerprinting is easy to perform and interpret. Use of PCR-based DNA fingerprinting may allow for a more detailed investigation of the epidemiology ofS. aureusmastitis in dairy cows.
Prevalence of human astrovirus serotypes in the Oxford region 1976–92, with evidence for two new serotypes
Authors: Lee T. W. , Kurtz J. B. 
Published: May 2009

SummaryResults of serotyping on 291 astrovirus-positive stools collected between 1976 and 1992 showed that about two-thirds (64.9%) were serotype 1. Infections were more frequent in the fourth quarter of the year and there was a suggestion that during the past 5 years serotype 1 has occurred with greater frequency in alternate years. Evidence is provided for the existence of two new serotypes, 6 and 7.
Insertion sequence IS200 fingerprinting ofSalmonella typhi: an assessment of epidemiological applicability
Authors: Threlfall E. J. , Torre E. , Ward L. R. , Dávalos-Pérez A. , Rowe B. , Gibert I. 
Published: May 2009

SUMMARYWhenPstI–generated digests of genomic DNA from each of the type strains of 49 of the Vi phage types ofSalmonella typhiwere probed with a PCR–amplified IS200 gene probe, all strains were found to possess at least 11 IS200 elements carried on fragments in the range 24.2–1.2 kb. Fourteen fingerprints were identified but two patterns designated IS200Sty1 and IS200Sty2 predominated. In one strain, a plasmid–mediated IS200 element was identified. When IS200 fingerprinting was applied to epidemiologically–unrelated strains ofS. typhiisolated in Ecuador, 3 patterns were identified in 10 strains belonging to 9 different phage types. It is concluded that Vi phage typing remains the method of choice for the primary differentiation ofS. typhibut that IS200 fingerprinting may be of limited use in laboratories which do not have access to phage typing.
Ribotyping as an epidemiologic tool forEscherichia coli
Authors: Tarkka E. , Åhman H. , Siitonen A. 
Published: May 2009

SUMMARYRestriction fragment length polymorphism of ribosomal RNA genes was analysed among 133Escherichia colistrains predominantly from blood and urine, including 21 isolates from faeces of healthy persons. The strains had also been characterized for their O:K:H serotypes, for the presence of P, S and type 1C fimbriae, non–P, non-S mannose–resistant haemagglutinins and haemolysin production.HindIII–digested genomic DNA was subjected to Southern blot analysis with either plasmid pKK3535 containingE. colirRNA operon or purified rRNA as a probe. Among the 133 strains 20 ribotypes were obtained. The distribution of strains into different ribotypes generally correlated with their O:K:H serotype. Ribotype variation within serotypes was mainly seen among strains with the K5 capsule. The origin of the strains or the presence of virulence-associated factors did not correlate with the ribotype. In conclusion, ribotyping appears to be a valuable method in epidemiologic studies especially when the serotyping methods are not available.
False positive legionella serology in campylobacter infection: campylobacter serotypes, duration of antibody response and elimination of cross-reactions in the indirect fluorescent antibody test
Authors: Marshall L. E. , Boswell T. C. J. , Kudesia G. 
Published: May 2009

SUMMARYSera from 83 patients with campylobacter gastroenteritis were examined for the presence of legionella antibodies by indirect immunofluorescence. Twenty–one patients (25%) had positive titres (≥ 16) including 11 patients with titres of ≥ 128. Legionella seropositivity persisted in 5 of 9 patients (55%) studied for 6–9 months. Campylobacter isolates were serotyped by the Penner scheme. Isolates associated with legionella seropositivity included Penner types 1, 2 and 4, the common endemic serotypes in England. Campylobacter blocking fluids were prepared from a range of Penner reference strains. The blocking fluid prepared from Penner type 11 was the most efficient at inhibiting the false-positive legionella titres. Using this absorption step legionella titres were inhibited from 24 of 26 patients (92%) with campylobacter but not from 8 patients with cultureproven legionnaires' disease. We recommend that this method is incorporated into routine diagnostic legionella serology in order to eliminate false-positive reactions due to campylobacter.
A study of a hospital cluster of systemic candidosis using DNA typing methods
Authors: Romano F. , Ribera G. , Giuliano M. 
Published: May 2009

SUMMARYA cluster of disseminatedCandida albicansinfections, which occurred at the Intensive Care Unit of the Department of Heart Surgery, was investigated. Ten patients became infected and seven died. A wide microbiological surveillance was carried out. A total of 14 isolates ofCandida albicans, four environmental and ten human, were examined using the Restriction Endonuclease Analysis (REA) of DNA. The isolates were classified into five different main groups. Five of the clinical isolates had the predominant pattern Ab and two more clinical strains were very closely related. Two more isolates from the emergency kit desk and the hands of a nurse gave the same REA profile. Such a relationship proved the epidemic nature of the cluster, with most of the patients cross-infected, and strongly suggested transmission on the hands of the staff as a determinant of the epidemic. Thus, REA has the potential to address many important questions in the study of nosocomial epidemiology ofCandida albicans.
The diagnosis of toxoplasmosis using IgG avidity
Authors: Holliman R. E. , Raymond R. , Renton N. , Johnson J. D. 
Published: May 2009

SUMMARYCurrent methods to establish the duration of toxoplasma infection in pregnant women and for the diagnosis of toxoplasmosis in the neonate or HIV infected patient have significant limitations. We assessed the precision of a commercial ELISA for the detection of toxoplasma specific IgG and adapted the assay to measure avidity using an elution agent washing step. The sensitivity and specificity of the ELISA were 100 and 75 % respectively and optimal measurement of avidity was achieved using 6 M urea as the elution agent.Toxoplasma lymphadenopathy of less than 3 months duration was associated with low avidity specific IgG but some discordant findings were recorded. Serial measurement of IgG avidity assisted the distinction between actively produced antibody in infants with congenital toxoplasmosis and passively acquired antibody of maternal origin in uninfected babies. There was no significant difference between avidity levels in HIV infected patients with or without cerebral toxoplasmosis.
Illness in a community associated with an episode of water contamination with sewage
Authors: Fogarty J. , Thornton L. , Hayes C. , Laffoy M. , O'Flanagan D. , Devlin J. , Corcoran R. 
Published: May 2009

SummaryFollowing an episode of water contamination with sewage in a rural Irish town, a community-wide survey of gastrointestinal-associated illness and health service utilization was conducted. Random sampling of households yielded residents who were surveyed using a self-administered questionnaire. Of 560 respondents from 167 (84%) households, equal proportions lived in areas known to have been exposed and unexposed to the contaminated water, although 65% of subjects reported using contaminated water. Sixty-one percent of subjects met the case definition. The most common symptoms among cases were abdominal cramps (80%), diarhoea (75%), appetite loss (69%), nausea (68%) and tiredness (66%). Mean duration of illness was 7·4 days. Only 22 % of cases attended their general practitioner. Drinking unboiled water from the exposed area was strongly associated with being a case. A substantial degree of community illness associated with exposure to contaminated water was observed. The episode ranks as one of the largest reported water-borne outbreaks causing gastrointestinal illness in recent times.
Epidemiology of measles in Taiwan: dynamics of transmission and timeliness of reporting during an epidemic in 1988–9
Authors: Lee M. S. , King C. C. , Chen C. J. , Yang S. Y. , Ho M. S. 
Published: May 2009

SummaryWe analysed nation-wide reported measles cases during the 1988–9 epidemic and found that longer duration and wider spread were two major characteristics of the outbreak. All the 22 county/city index cases were reported with a delay of > 4 days and 64% were aged 5–14 years. This epidemic occurred mainly among 5–14-year-old school-children (59%), infants under 1 year (19%), and pre-school children (18%). The overall attack rate was 0·63 cases per 10000 population, with the highest attack rate (7·4 cases per 10000 population) occurring in infants. Among 280 confirmed cases <15 months of age, 9-month-old infants (42 cases) had a higher risk of measles and peaked at 10 months (49 cases). This epidemic started in March 1988 among 5–9-year-old children in the northern suburban area, then spread to Taipei City and neighbouring counties or cities. It continued to spread from the northern to southern and western areas during the summer vacation and New Year holidays. Multiple logistic regression analysis showed that the delay of measles reporting was strongly associated with the cases infected early in the epidemic (OR= 6·9,P< 0·001) and reported from teaching hospitals (OR = 2·6,P< 0·001). The reappearance of high attack rates among 5–9-year-old children in the 1985 and 1988–9 measles epidemics in Taiwan indicated the persistence of pockets of susceptible individuals even after mass immunization.
A pseudo-outbreak of salmonellosis
Authors: Joce R. E. , Murphy F. , Robertson M. H. 
Published: May 2009

SummaryDuring July 1991, a single laboratory reported an increased number of an unusual salmonella isolate. An outbreak control team was convened. A case was defined as an individual with diarrhoea from whose faecal sample Salmonella hadar was isolated after 1 July 1991. By 30 July, 90 isolates had been identified and 57 persons interviewed including 39 primary cases. Interviews failed to identify any common features among the cases. A review of the laboratory procedures revealed that the selenite enrichment medium was inoculated using the spoon from the stool collection kit after it was used to emulsify the faecal sample with saline for microscopy. Salmonella hadar was isolated from this saline. Once this practice was stopped, no further isolates of S. hadar were made. This pseudo-outbreak is a powerful reminder to verify the existence of an outbreak, especially when epidemiological data are inconsistent.
Epidemiology of invasiveHaemophilus influenzaeinfections in England and Wales in the pre-vaccination era (1990–2)
Authors: Anderson E. C. , Begg N. T. , Crawshaw S. C. , Hargreaves R. M. , Howard A. J. , Slack M. P. E. 
Published: May 2009

SummaryThis survey defined the pattern of invasiveHaemophilus influenzaeinfections during 1990–2 in six regions in England and Wales during the pre-vaccination era providing a baseline against which any changes in patterns of disease due to the introduction of theHaemophilus influenzaetype b vaccination programme can be monitored. A total of 946 cases of invasiveHaemophilus influenzaewere recorded during the survey period of which almost 90 % were due to type b and most of the remainder were non-typeable. Type b infections occurred predominantly in children less than 5 years of age (88%) with the highest attack rate in male infants in the 6–11 month age group. Diagnostic category varied with both age and serotype; meningitis was the commonest presentation overall but pneumonia and bacteraemia were more common in adults and non-typeable isolates. Mortality was highest in neonates and the elderly (over 65 years of age) who were more likely to have an underlying predisposing condition than older children and adults. Children under 5 years of age had a higher case fatality rate for non-typeable than for type b infections. Ampicillin resistance was 15% and there were no cefotaxime resistant type b isolates.
Tuberculosis in Inner London: evidence for an increase in young adults and immigrants
Authors: Barkham T. M. S. , Drury A. , Pearson A. D. , Dybowski R. , Atkinson H. 
Published: May 2009

SummaryWe report a marked increase in the rate of notifications of tuberculosis in young adults in the London Borough of Lambeth. Analysis of notifications made to the Proper Officer over a 10-year period showed that the age specific notification rate in the cohort aged 20–44 years increased from 30/100000 in 1983 to 51/100000 in 1992. Analysis of St. Thomas' Hospital laboratory records of patients seen between 1984 and 1991 from whom Mycobacterium tuberculosis was isolated showed an increase in the number of patients of African origin from five in the first half of the study period (1984–7) to 25 in the second half (1988–91): 21 of these 25 had immigrated into England within 4 years of their illness. This finding is being further investigated in a prospective study of ethnicity, travel history and date of immigration of Lambeth residents notified with tuberculosis.
An outbreak of viral gastroenteritis associated with adequately prepared oysters
Authors: Chalmers J. W. T. , McMillan J. H. 
Published: May 2009

SummaryOver Christmas 1993, an outbreak of food poisoning occurred among guests in a hotel in South West Scotland. Evidence from a cohort study strongly suggested that raw oysters were the vehicle for infection, probably due to a Small Round Structured Virus (SRSV). Detailed enquiry about the source and preparation of the oysters revealed no evidence of any unsafe handling at any stage in the food chain, nor any evidence of bacterial contamination. It is suggested that the present standards of preparation and monitoring are inadequate to protect the consumer, and that bacteriophage monitoring may be a useful method of screening for viral contamination in future.
Hand-genital transmission of genital warts? An analysis of prevalence data
Authors: Fairley C. K. , Gay N. J. , Forbes A. , Abramson M. , Garland S. M. 
Published: May 2009

SummaryThe role of hand-genital transmission in the aetiology of genital warts is unclear. However this route is suggested by a number of observations including the relatively high proportion of genital warts in children which contain HPV types 1–4 (15% for children and 2% for adults). We compared two transmission models; one which assumes that hand-genital transmission occurs and one that it does not, and determined the conditions in which each model can reflect the available prevalence data. Hand-genital transmission provides a simple explanation of the observed differences in the proportions of genital warts containing HPV types 1–4 and 6/11 in children and adults. If hand-genital transmission does not occur, the observed difference could only be explained by an eightfold greater probability of transmission to children of types 1–4 than types 6/11, or by an eightfold greater duration of infection with types 1–4. Our findings provide support for the view that genital warts may be transmitted by hand-genital contact.
Evidence for a high prevalence of spotted fever group rickettsial infections in diverse ecologic zones of Inner Mongolia
Authors: Liu Qing-Huai , Chen Guo-Ying , Jin Yan , Te Meng , Niu Li-Chun , Dong Shi-Ping , Walker D. H. 
Published: May 2009

SummaryA 3-year study of spotted fever group rickettsial ecology in Inner Mongolia revealed that nearly half of the human population tested had antibodies toRickettsia sibiricadetected by complement fixation test. Infected persons, ticks and a high proportion of seropositive livestock and wild rodents were found in all five vegetation zones (desert, steppe, forest, forest-grassland and grassland).
Salmonella outbreak from microwave cooked food
Authors: Evans M. R. , Parry S. M. , Ribeiro C. D. 
Published: May 2009

SummaryFollowing a buffet meal served to six guests at a private domestic function, five of the guests and the host developed symptoms of food poisoning.Salmonella enteritidisphage type 4 (PT4) was isolated from all four individuals who submitted faecal samples for investigation. Leftover samples of a savoury rice dish consumed by all six ill persons contained 6×103/gmSalmonella enteritidisPT4. The rice salad comprised boiled rice, raw carrots, eggs, cheese and curry powder. The curry powder and remainder of the pack of six eggs were negative on microbiological analysis. The rice dish had been prepared by heating in a 500 W microwave oven with a rotating turntable on full power for 5 min. Although the hazards of inadequate microwave cooking are well recognized, this is only the second outbreak of food poisoning from microwave cooking to be reported.