bluuebunny/crossref_metadata_2025 huggingface dataset:
The virulence of clinical and environmental isolates ofCampylobacter jejuni
Authors: Newell D. G. , McBride H. , Saunders F. , Dehele Y. , Pearson A. D.
Published: October 2009

The virulence ofCampylobacter jejuniandC. coliisolated from various water sources was compared with that of clinical strains byin vitroassays of adhesion, invasion and cytotoxicity to HeLa cells. Variation in degree of attachment was observed, but this did not appear to be related to strain source, However, water strains were less invasive and less cytotoxic to HeLa cells than clinical strains as shown by immunofluorescence and electron microscopy.

These differences were particularly evident between clinical and water isolates of the same serotype and biotype implicated in an outbreak of campylobacter enteritis in a school. The enhanced virulence of the clinical isolates, possibly induced by passage, was confirmed by colonization tests on infant mice.
The assessment and application of a bacteriocin typing scheme forClostridium perfringens
Authors: Watson G. N.
Published: October 2009

A collection of 50 bacteriocins was assembled and used to type 802 isolates ofClostridium perfringensfrom food poisoning outbreaks and a variety of other sources. It was found that strains of the same serotype within an outbreak showed similar patterns of susceptibility to bacteriocins, and the use of a ‘one difference’ rule is proposed for interpretation of the typing patterns of epidemiologically related strains. Isolates of different serotype or of the same serotype isolated from different sources produced many variations in bacteriocin susceptibility patterns.

Two computer programs were developed to assist in the interpretation of bacteriocin typing patterns. Their use showed that related and unrelated strains formed different clusters and enabled a range of the 20 most discriminatory bacteriocins to be selected.

Isolates ofC. perfringensfrom a wide range of sources were screened for their ability to produce bacteriocins. A much greater proportion of the strains from food poisoning outbreaks was bacteriocinogenic than were isolates from human and animal infections, various foods and the environment. The relevance of these findings to the occurrence ofC. perfringensfood poisoning is discussed.
The risk of leptospirosirs in United Kingdom fish farm workers. Results from a 1981 serological survey
Authors: Gill O. N. , Coghlan J. D. , Calder I. M.
Published: October 2009

Less than one per cent of serum samples taken from 257 fish farmers in 1981 had agglutinating antibodies to strains of Leptospira interrogans of serogroup Icterohaemorrhagiae at a titre of 30 or greater. Compared with the results from other serological surveys, this agglutinating antibody prevalence suggests that fish farming does not have a high occupational risk for leptospirosis. Between 1961 and 1981 the incidence in fish farmers was about 33 per 100000 person years at risk. During the same period the incidence in the general adult male population was 0·137 per 100000 person years at risk, so that fish farming had a moderately increased risk of Icterohaemorrhagiae serogroup infection (relative risk = 243). No one particular risk factor within fish farming could be reliably identified and therefore recommendations to reduce the risk can only be general.
Antigenic heterogeneity among influenza A(H3N2) field isolates during an outbreak in 1982/83, estimated by methods of numerical taxonomy
Authors: Beyer W. E. P. , Masurel N.
Published: October 2009

Fourteen influenza A(H3N2) field isolates, mainly obtained during the first weeks of the 1982/83 influenza epidemic in The Netherlands, and nine influenza A(H3N2) reference strains were examined by means of haemagglutination inhibition (HI) tests with 23 potyclonal ferret sera. The resulting HI patterns were subjected to various methods of numerical taxonomy using, among others, taxonomic distance and correlation between strains for resemblance coefficients. Marked differences between distance and correlation coefficients were found in strains which differed in avidity only. The field isolates could be divided into four groups in respect of their taxonomic resemblance to the reference strains. The same grouping was found for five of the field isolates by testing these against 200 human sera.
Mosquito-borne arboviruses in Norway: further isolations and detection of antibodies to California encephalitis viruses in human, sheep and wildlife sera
Authors: Traavik Terje , Mehl Reidar , Wiger Richard
Published: October 2009

Seven virus strains antigenically related to the California encephalitis (CE) virus group were isolated from NorwegianAedesspp. mosquitoes collected in 1976. So far CE viruses have been isolated from five differentAedesspp. in Norway. Furthermore, two virus strains related to the Bunyamwera group were isolated fromAnopheles claviger.

Antibodies to CE viruses were demonstrated in 22% of 1014 military recruits tested. Among 91 soldiers who were monitored by monthly blood samples during the mosquito season, seroconversions were detected in 11 individuals. Specific IgM antibodies were found in seven of them. Disease symptoms in connexion with the CE virus infections were not seen. The prevalence of CE antibodies in patients with CNS or respiratory infections was not higher than in control groups. Seroconversions were not seen in any of the groups.

Screening of sheep sera from six different areas in northern Norway indicated significantly different degrees of CE virus activity. Passerine birds may be important CE virus hosts, while small rodents seem unimportant. Specific IgM antibodies were detected in the sera of one of three hares and one of two squirrels.

Of the methods used, single radial haemolysis (SRH) and immuno-electroosmophoresis (IEOP) seemed to be well suited for serological screenings. However, an indirect immunofluorescence antibody test (IFAT) which was used may be an attractive alternative if high-quality anti-species conjugates are available. The haemagglutination-inhibition (HI) test used gave a high number of false positive results.
Hospital infection caused by non-typableStaphylococcus aureus: application of reverse typing
Authors: Martín-Bourgon C. , Berrón S. , Casal J.
Published: October 2009

Hospital infections caused by strains ofStaphylococcus aureusnon-typable (NT) by phages have occurred in three Spanish hospitals since 1981. Reverse typing allowed characterization of the strains in all three cases.
Carriage ofNeisseria meningitidisandNeisseria lactamicain a school population during an epidemic period in Spain
Authors: Saez-Nieto J. A. , Dominguez J. R. , Monton J. L. , Cristobal P. , Fenoll A. , Vazquez J. , Casal J. , Taracena B.
Published: October 2009

A study was made of the incidence ofNeisseria meningitidisandN. lactamicain a school population; 2470 children aged between 5 and 7 years were studied from four schools in Alcala de Henares (Madrid). Nasopharyngeal swabs were taken in June, November and March, between 1979 and 1983.

In all the surveys except one, the proportion of carriers ofN. lactamicawas higher than that ofN. meningitidis, reaching a ratio of about 2:1 in the complete study.

The predominant serogroup of meningococcus found was B (41%), with nongroupable strains reaching 43%. A study of serotypes within group B showed a predominance of nontypable strains (48·5%), while those strains considered to be most virulent (types 2 and 1, 8, 15) reached 40%.

Eighteen per cent ofN. lactamicastrains were observed to agglutinate with antimeningococcal sera whilst the remainder of the strains were rough. When these strains were studied with the antiscrum-agar technique, using antimeningococcal sera, a high percentage of strains cross-reacted with the meningococci. The susceptibility of strains to sulphadiazine, penicillin, ampicillin, chloramphenicol, rifampicin and spiramycin was determined.

Finally an analysis was made of the effect that an elevated colonization rate ofN. lactamicamight have on colonization by meningococi. The necessity of using fine epidemiological markers in tracing virulent strains in a population at risk is stressed. Selective prophylactic measures are also necessary.
Salmonellae in sewage sludge and abattoir effluent in South-east Scotland
Authors: Linklater K. A. , Graham Margaret M. , Sharp J. C. M.
Published: October 2009

A survey into the prevalence of salmonella organisms in sewage in the Borders Region of South-east Scotland is described. A total of 317 isolates representing 34 different serotypes were made, of which only 5 serotypes appeared in animals, supporting the view that the spreading of sewage sludge on to pastureland presents little risk to livestock provided the recommended guidelines are followed. Nevertheless, Salmonella typhimurium phage type 12, identified in sewage, was also recovered from animals in incidents on 11 farms, including 4 which had received sludge from this source. A further 48 isolates (13 serotypes) were obtained from the parallel monitoring of abattoir effluents, indicating that the background level of salmonella infection in the animal population appears to be low in comparison to that in humans.
Concurrent outbreaks of influenza A and influenza B
Authors: Spelman D. W. , McHardy C. J.
Published: October 2009

During the winter of 1982 concurrent outbreaks of influenza A and influenza B occurred. The epidemiology and clinical features of 151 cases referred during this time are described, and patients are discussed according to age and presenting clinical syndrome: croup was the commonest presentation in young children, a typical influenza syndrome predominated in young adults, while older patients were more likely to have lower respiratory tract infection. There was no significant difference between the clinical features of influenza A and influenza B. Unusual clinical features include rash, exudative tonsillitis and the need for myringotomy during the course of influenza.
Surveillance of respiratory viral infections by rapid immunofluorescence diagnosis, with emphasis on the epidemiological development of respiratory syncytial virus infections
Authors: Ånestad G.
Published: October 2009

Surveillance of certain respiratory viral infections by applying immunofluorescence (IF) examinations to samples of nasopharyngeal secretions has been evaluated using a simplified procedure for the preparation of cell smears. Samples from 711 children living in different parts of Norway were examined during the winter 1982/83 and a positive diagnosis was made for 290 children (41%). Temporal epidemic peaks were observed for respiratory syncytial virus (RSV), parainfluenza virus type 3 and influenza virus. On the other hand, the monthly number of negative samples was almost constant throughout the period. Differences in timing of RSV outbreaks were observed between two regions in Norway. Compared to rapid IF diagnosis, RSV notifications obtained by serological examinations were delayed by several weeks. Rapid virus diagnosis by IF examinations with our simplified procedure for preparation of nasopharyngeal samples seems to be suitable for the epidemiological surveillance of respiratory viral infections, both for its simplicity of preparation of the samples and for its accuracy in defining the time of the actual virus infection. Nevertheless, the method is not without pitfalls; a close cooperation between those who take the specimens and the laboratory is essential, and the IF examinations should be performed by an experienced microscopist.
The interplay of host and organism factors in infection of the mouse genital tract by Mycoplasma pulmonis
Authors: Taylor-Robinson D. , Furr Patricia M.
Published: October 2009

Mice of strain TO, in groups of ten, were inoculated intravaginally with Mycoplasma pulmonis organisms. Seven mice became infected after inoculation of organisms with strong haemadsorptive capacity, four after inoculation of organisms with diminished adsorptive capacity following ten passes in medium, and none after inoculation of apparently non-adsorbing organisms which had been passed 50 times. There appeared to be a correlation, therefore, between the ability to infect and the cytadsorptive capacity of the organisms. There was only a minimal vaginal polymorphonuclear leucocyte (PMNL) response in the infected mice and most of them had ceased to be infected by 35–42 days. In contrast, mice treated with progesterone had enhanced infections; all those given strongly haemadsorbing organisms, and organisms passed ten times, became infected and remained so for at least 42 days. Furthermore, at least ten fold more organisms were recovered from progesterone-treated than from untreated mice, and the PMNL response was much greater. Most of the progesterone-treated mice given organisms passed 50 times did not become infected, but some did, and the organisms recovered from them were fully cytadsorptive. It is postulated that a few cytadsorbing organisms in this inoculum were induced to infect under the enhancing effect of progesterone.
A survey of campylobacter in animals
Authors: Manser P. A. , Dalziel R. W.
Published: October 2009

A survey ofCampylobacterspecies in the faeces or rectal contents of domestic animals was carried out using direct and enrichment culture methods. Campylobacters were isolated from 259 (31 %) of 846 faecal specimens. The highest isolation rate was found in pigs (66%); lower rates were found in cattle (24%) and sheep (22%). In pigs all the isolates wereC. coli, in sheep and cattle about 75% wereC. jejuni. Only five isolations ofC. fetus suhsip. fetuswere made, all from cattle. More pigs with diarrhoea hadC. coliin their faeces than healthy pigs (77% vs 47 %), but such a clear difference in isolation rate between sick and healthy animals was not seen in cattle or sheep.

The enrichment method increased the total isolation rate ofC. jejuniandC. coliby 33%, but for cattle specimens it increased it by 69% (from 6·5% to 21%). However, the enrichment method failed to detect 16% of positive specimens (mainlyC. coli), so direct and enrichment methods should be used for the culture of campylobacters from animal faeces. The results show that cattle, sheep and pigs constitute a large potential source of campylobacter infection for man.
Salmonellas in Danish pigs: a comparison of three isolation methods
Authors: Skovgaard Niels , Christensen Sven Gade , Gulistani A. W.
Published: October 2009

Caecal samples from 350 Danish bacon pigs were investigated for salmonella using three methods of isolation. (1) Direct inoculation of 1 g of faeces into 10 ml of Muller–Kaufmann medium (MK medium) with addition of 0·3% Teepol 610 and subculture on Brilliant Green lactose sucrose phenol-red agar (BLSF agar) with 0·3% Teepol G10. (2) Pre-enrichment of 5 g of faeces into buffered peptone water with addition of 1% Teepol 610 followed by enrichment of 1 ml in 10 ml MK medium with 1% Teepol 610 and subculture on BLSF agar with 0·3% Teepol. (3) Incubation of 0·1 ml of the pre-enrichment (2) into 10 ml Rappaport-Vassiliadis medium (RV 10 medium) incubated at 43°C, subculture on BLSF agar.

The MK media with and without pre-enrichment yielded higher findings than the RV 10 media. In total, 28 (8%) of the pigs were found positive, representing 11 (7·4%) of a total of 142 herds investigated. Lymph glands were collected at a later date from six of the positive herds. Five of the herds were found positive.

The number of salmonellas in the glands was low, probably less than ten per gram.
Campylobacter infection in urban and rural populations in Scotland
Authors: Sibbald C. J. , Sharp J. C. M.
Published: October 2009

A review of campylobacter infection in Scotland over five years (1978–82), during which 7808 human isolates were recorded (mean annual isolation rate of 30 per 100000), revealed differences in the epidemiology of the disease between rural and urban populations which were not apparent in the national data. The incidence of infection in the two rural areas studied was greatest in the early months of the year, whereas that in the two urban areas showed a third-quarter predominance. In both urban and rural populations, age-specific infection rates were highest in children less than 5 years old, but this trend was more pronounced in rural than urban populations. Conversely, secondary peaks in age-specific infection rates observed in young adults were more pronounced in the urban than rural populations.

It is postulated that rural children were being infected by campylobacters at an early age by drinking contaminated raw milk which was not normally available to city residents. The lower incidence in adults in the rural populations is interpreted as indicating more widespread immunity, resulting from greater exposure to infection during childhood. The effect of compulsory heat treatment of milk sold in Scotland, introduced in August 1983, is currently being studied.
Demonstration of cross-reactive antigens in F38 and related mycoplasmas by enzyme-linked immunosorbent assay (ELISA) and immunoblotting
Authors: Kibe M. Kanyi , Bidwell D. E. , Turp P. , Smith G. R.
Published: October 2009

The ELISA and an immunoblotting technique were used to study F38-type mycoplasmas – an important cause of contagious caprine pleuropneumonia – and a number of related mycoplasma species, subspecies, types or serogroups.

Two-way ELISA cross-reactivity was demonstrated between five mycoplasmas, namely strain F38,Mycoplasma mycoidessubsp.mycoides(LC strain),M. equigenilalium, M. primatumand bovine serogroup 7. In addition one-way cross-reactivity was demonstrated between F38 and each of the following mycoplasmas:M. mycoidessubsp.mycoides(two SC strains),M. mycoidessubsp.capri, and bovine serogroup L. F38 andM. capricolumdid not cross-react.

Immunoblot analysis, unlike ELISA, revealed that F38 andM. capricolumwere closely related. At least four major protein antigens were shared between F38,M. mycoidessubsp.mycoides(SC and LC strains),M. mycoidessubsp.capriand bovine serogroup 7. The ELISA cross-reactions (above) shown byM. equigenitaliumandM. primatumwith each other, with F38 and with other mycoplasmas were not apparent by immunoblotting.
Superficial tuberculous lymphadenitis in Merseyside: 1969–1984
Authors: Wilkins E. G. L. , Roberts C.
Published: October 2009

The actiology, epidemiology and clinical presentation of 137 bacteriologically confirmed cases of superficial mycobacterial lymphadenitis identified at the Liverpool Public Health Laboratory between 1969 and 1984 were reviewed. Despite a fall in pulmonary and total extrapulmonary isolates, the annual recovery of mycobacteria from lymph nodes remained relatively constant. Mycobacterium tuberculosis was the cause of infection in 121 patients (88·3%), M. bovis in 6 and the remaining 10 isolates were atypical mycobacteria. In European patients (68·6%) the highest incidence was in the elderly, whereas in non-Europeans (31·4%) the disease almost exclusively occurred in the third and fourth decades. The proportion of isolates from non-Europeans reflected the size of the immigrant population and increased during the period of study.
The use of a sandwich ELISA for the detection of staphylococcal enterotoxin A in foods from outbreaks of food poisoning
Authors: Wieneke Antonnette A. , Gilbert R. J.
Published: October 2009

Foods from outbreaks of food poisoning were examined for the presence of staphylococcal enterotoxin A (SEA) by a sandwich ELISA using microtitre trays as the solid phase and SEA antibodies raised in sheep.

The presence of SEA was confirmed by neutralization tests. The toxin was detected in 12 of 15 foods from separate outbreaks of staphylococcal food poisoning; all 15 foods contained a strain ofStaphylococcus aureuswhich produced SEA. For most foods a simple extraction procedure without a concentration step was sufficient to detect the toxin. The method was semi-quantitative and recoveries of SEA added to control foods varied from 30 to 80%. The foods from outbreaks contained between 1 and 10 μg of SEA/100 g. SEA was not found in foods from 21 outbreaks in which an SEA-producing strain ofStaph. aureuswas not isolated.
Effect of specific humoral immunity and some non-specific factors on resistance of volunteers to respiratory coronavirus infection
Authors: Callow Kathleen A.
Published: October 2009

Thirty-three volunteers were inoculated intranasally with coronavirus 229 E, and their responses monitored by antibody rises, symptomatology and virus excretion. These were related to their pre-trial immune status as indicated by concentrations of specific antibodies and non-specific proteins in serum and nasal washings. Both circulating and local specific antibodies were associated with protection from infection and disease, but only specific IgA antibodies of either type appeared to shorten the period of virus shedding. Although total secretory IgA was significantly associated only with reduction of symptoms, total protein in nasal washings appeared to protect against infection also, indicating that other locally produced proteins, not identified, may be associated with resistance.

Two of the many factors which may affect the concentration of circulating and local protective proteins and thus influence the outcome of virus inoculation, namely, sex of the volunteer and the interval since the previous cold, were examined. Male volunteers or volunteers who had had evidence of a recent respiratory infection were less likely to be infected, but if they were infected, they had lower clinical scores and stopped shedding virus earlier than the rest. These groups possessed higher concentrations of specific antibodies and non-specific proteins in their pre-challenge sera and/or nasal washings. The significance of these findings is discussed.
TracingSalmonella typhimuriuminfections
Authors: Barker Ruth M.
Published: October 2009

Since the low point of 1977 the incidence of infection attributed toSalmonella typhimuriumin England and Wales has shown a steady increase with a total of 4956 cases reported in 1982 (OPCS, 1985). Although the number of general outbreaks and family outbreaks increased by 24 % and 54 % respectively between 1981 and 1982, the greatest increase (55%) was in the number of sporadic cases reported (PHLS, 1984). The cause of the recent increase in human infection is not known but may be associated with bovine infection and an explanation for the rise in sporadic cases could be that they comprise unrecognized outbreaks due to common food products distributed over wide geographical areas for long periods of time because of deep freezing (Galbraith, 1985). This hypothesis has prompted the Communicable Disease Surveillance Centre to mount a case-control study comparing sporadic cases ofS. typhimuriuminfection with an unaffected control group in several parts of the country to find the vehicles of infection. Such an approach requires precise strain identification and detailed epidemiological information.
Detection ofClostridium difficiletoxins by enzyme immunoassay
Authors: Krishnan C.
Published: October 2009

An enzyme-linked immunosorbent assay (ELISA) for the rapid diagnosis of antibiotic-associated colitis (AAC) is presented. Commercially available antisera toClostridium difficiletoxins contain antibodies to other antigens found in non-toxigenicC. difficileand other bacteria. Removal of these unwanted antibodies by absorption increased the specificity of ELISA for detection ofC. difficiletoxins. Specimens tested included 40 faecal extracts positive for cytotoxicity from cases of AAC, 30 diarrhoeic and 30 well-formed stools negative for cytotoxicity and 50 culture filtrates of toxigenic and non-toxigenicC. difficileand other clostridial species. Use of absorbed sera reduced false-positive reactions observed with faecal specimens frqm 23 to 8 %. About 90 % of specimens that were positive by the tissue culture cytotoxicity test were positive by ELISA using the absorbed sera. The relative merits of ELISA and other methods for the rapid diagnosis of AAC are discussed.
Evaluation of procedures for hygienic hand-disinfection: controlled parallel experiments on the Vienna test model
Authors: Rotter M. L. , Koller W. , Wewalka G. , Werner H. P. , Ayliffe G. A. J. , Babb J. R.
Published: October 2009

Controlled parallel experiments were performed on the Vienna test model for the evaluation of procedures for hygienic hand-disinfection in three laboratories (Vienna, Mainz, Birmingham). The degerming activity of four procedures, each taking 1 min, was assessed repeatedly and compared with that of a standard disinfection procedure (ST) using isopropanol 60 % (v/v). The mean log reductions (mean log RF) for each procedure were as follows: n−propanol 50% (v/v) 4·85 and 5·14 in Vienna (V) and Mainz (M) respectively, ethanol 70 % (v/v) + chlorhexidinegluconate 0·5% (w/v), 4·01 (V), 3·76 (M) and 4·00 in Birmingham (B). Washing procedures were less effective, mean log RF 's of 3·19 (V), 3·49 (M) and 3·04 (B) were obtained with povidone-iodine soap, and 2·91 (V), 3·37 (M) and 3·27 (B) with a liquid phenolic soap. Analysis of variance on the data from Vienna and Mainz revealed significant differences of means not only between procedures (‘preparations’) but also on repeat testing. To compensate for the influence of variables such as test subjects, laboratory and day, the Vienna test model provides a method of standardization by testing a ST in parallel with the test procedure (P).

Standardization of the results was obtained by pair-wise substraction, log . Analysis of variance on the resulting values demonstrated that comparability of the results between laboratories and on repeat testing was achieved. The relative variation of the measurements within the laboratories ranged from 0·9 to 4·2%. As assessed by power-analysis, a disinfection procedure will be detected as significantly (P= 0·1) inferior to the standard processes in 95 of 100 experiments if it produces a mean log RF that is at least 0·55–0·65 log units smaller than that of the standard.
The impact of physico-chemical stress on the toxigenicity ofVibrio cholerae
Authors: Miller Christopher J. , Drasar Bohumil S. , Feachem Richard G. , Hayes Richard J.
Published: October 2009

The expression of toxigenicity byVibrio cholerae, before and after exposure to various conditions of salinity, pH and cation composition and concentration, has been measured. Exposure to these conditions did not select for hyper- or hypo-toxigenic strains. This suggests that toxigenicV. choleraeO 1 are unlikely to lose their toxigenicity when exposed to environmental stress and thatV. choleraetoxin production is not a response to the stresses included in this study. These results are consistent with an aquatic reservoir for toxigenicV. choleraeO 1.
The frequency distribution and consistency of assimilation biotypes ofCandida albicans
Authors: Hellyar A. G.
Published: October 2009

Two hundred and fifty clinical strains ofCandida albicansand six isolates from a cross-infection outbreak were studied for their ability to assimilate 19 carbohydrates in the API-20C system (API Laboratory Products Ltd., Basingstoke, UK). The assimilation profiles were stable on repeat testing; at intervals in the 72 h duration of the test; and when incubated at different temperatures.

Although not a complete system of biotyping, the API-20C system shows high typability, and fair reproducibility and discrimination, having a limited role in indicating which isolates should be typed by more elaborate methods.
Biochemical and serological investigations on clinical isolates of klebsiella
Authors: Simoons-Smit A. M. , Verweij-van Vught A. M. J. J. , Kanis I. Y. R. , Maclaren D. M.
Published: October 2009

A series of 925 clinical isolates of klebsiella was examined by serological and biochemical typing. To perform serological typing (capsular swelling) 77 capsular antisera were prepared, tested against the type strains and grouped in 13 pools. With this serotyping method 80% of the cultures were typable and 63 distinct types could be recognized.

All strains were typable biochemically by means of the numerical coding system of the API-20E system supplemented by digits derived from 15 additional conventional biochemical tests. With the API-20E system 24 different biotypes could be distinguished whereas the combination of API-20E and the 15 additional tests produced 93 biotypes. Maximum discrimination of strains was achieved by the combination of serological and biochemical typing (256 bioserotypes). The reproducibility, typability and discriminating power of the biotyping system was not inferior to serotyping. For epidemiological purposes biotyping can replace serotyping ofKlebsiellaspecies, especially in laboratories less well equipped.
Ventilation conditions and air-borne bacteria and particles in operating theatres: proposed safe economies
Authors: Clark R. P. , Reed P. J. , Seal D. V. , Stephenson M. L.
Published: October 2009

Concentrations of air-borne bacteria and particles have been measured in turbulently ventilated operating theatres in full flow, half flow and zero flow conditions. Increased air-borne challenge produced by human activity and by mechanical cleaning procedures is demonstrated: die-away of this contamination is shown to be related to the ventilation rate. Ventilation can be reduced or turned off at night and during weekends, and cleaning can also be carried out, without increased risk of infection if full flow is restored one hour prior to preparation for surgery. Areas surrounding the theatres should remain at positive pressure with regard to the general hospital environment during low or no flow periods. The implementation of such energy-saving policies will substantially reduce theatre running costs without introducing infection hazards.
The relationship between faecal endotoxin and faecal microflora of the C57BL mouse
Authors: Rogers M. J. , Moore R. , Cohen J.
Published: October 2009

We studied the effect of oral selective antibiotic decontamination (SD) on the faecal endotoxin content and microflora in individual C57BL mice. Suppression of the coliform count was associated with an initial rise in faecal endotoxin concentration from 0·1 to 3·1 mg/g wet faeces during the first week of SD, which fell to 0·04 mg/g during the second week of treatment. Cessation of SD resulted in an immediate sharp increase in coliform count followed by its decline and gradual recovery to pro-treatment counts. Faecal endotoxin levels followed a parallel course. SD did not effect significantly the counts of lactobacilli, baeteroides and enterococci.

It appears that the coliform population is responsible for the overall level of faecal endotoxin, and that during the initial period of SD endotoxin levels are elevated, an effect which may be mediated by antibiotic-enhanced release of endotoxin.
An epidemic of acute diarrhoea in rural southern India associated with echovirus type 11 infection
Authors: Patel J. R. , Daniel J. , Mathan V. I.
Published: October 2009

An epidemic of diarrhoea with two distinct waves affected a village of 1375 people in southern India in 1983. The first wave of the epidemic, from the last week of December 1982, had a sharp peak in January 1983 and was over by March. Echovirus type 11 was isolated from patients, who also had a serum antibody response to the virus. During the second wave of the epidemic, from May to September 1983, the clinical features were different andShigella flexneriwas isolated without significant viral isolates. Infection during the first wave did not protect from the second wave. Virus isolation was in human intestinal tumourderived differentiated epithelial cell lines; such cell lines may be useful for the isolation and identification of entcroviruses in clinical samples.
Field trials of a new sub-acute rodenticide flupropadine, against wild Norway rats (Rattus norvegicus)
Authors: Buckle A. P.
Published: October 2009

Fifteen experimental treatments with rodenticidal baits containing 0·1, 0·15 or 0·2% flupropadine were conducted on farmsteads against Raltus norvegicus infestations. Eight treatments were completely successful and the others gave kills ranging from 36 to 72% in 28 days. Treatments with 0·1 and 0·15% flupropadine were less successful against large infestations than against small ones. Flupropadine was most successful at 0·2% but still gave incomplete kills on farms where abundant alternative food was available. The compound was more effective than acute poisons in achieving complete control of Norway rat infestations, but was less reliable in doing so than anticoagulants. On the other hand, many flupropadine treatments gave quicker control and used smaller quantities of bait than anticoagulant treatments.
Pen and field trials of flupropadine against the house mouse (Mus musculus L.)
Authors: Rowe F. P. , Bradfield A. , Swinney T.
Published: October 2009

Laboratory and field trials were conducted to determine the efficacy of the candidate rodenticide flupropadine against the house mouse (Mus musculus L.). In laboratory feeding tests, family groups of wild mice maintained in pens and conditioned to feeding on plain foods were offered flupropadine at either 0·10%, 0·15%, 0·18% or 0·20% in pinhead oatmeal bait. Overall mortalities in replicated 21-day treatments were 66/71 (93·0%), 71/79 (89·9%), 72/70 (94·7%) and 69/75 (92·0%) respectively.

In 17 field trials carried out against mice infesting farm buildings, flupropadine was used at 0·10%, 0·15% and 0·18% in oatmeal bait. Mean treatment success, estimated from live-capture and mortality data, was 88·6%, 96·2% and 96·6% respectively.

Flupropadine was found to be as near effective against mice as calciferol/warfarin and the second-generation anticoagulant rodenticides difenacoum, bromadiolone and brodifacoum. In further comparison with the anticoagulants, treatment with flupropadine bait achieved markedly quicker control.
Chemical closet treatment of typhoid carrier faeces
Authors: Harvey R. W. S. , Price T. H.
Published: October 2009

An investigation to test the efficiency of chemical closets in treating excreta from typhoid carriers is described. The use of these closets kept a stream, which had in the past frequently contained Salmonella typhi, typhoid free for 24 months. Selenite broth as made in this laboratory, containing a final concentration of 0·8% sodium hydrogen selenite when inoculated with the water sample, was significantly better than commercial selenite brilliant green enrichment broth for the recovery of S. typhi.
Rabies vaccines and interferon
Authors: Turner G. S.
Published: October 2009

Samples of Fermi, Semple, modified Semple, Duck embryo and tissue culture rabies vaccine were inoculated by different routes and in different doses into rabbits, mice and hamsters. The vaccines induced neither detectable interferon nor immediate protection against lethal challenge with CVS rabies virus.

Under similar conditions, high but transient levels of interferon were induced in control animals of the same species with the polynucleotide complex Poly I.C. Hamsters but not mice were protected by Poly I.C.-induced interferon.

No autointerference by vaccine with challenge virus was established. Vaccineinduced protection in mice was directly related to immune response.
Diphtheria infection in North West Canada, 1969, 1970 and 1971
Authors: Jellard C. H.
Published: October 2009

In three years,Corynebacterium diphtheriaewas isolated from 1238 people, consisting of 820 North American Indians or Metis, 318 people of Caucasian origin, 97 Eskimos and 3 Asiatic Indians. Diphtheria infection of the throat, nose, ears and skin was common in the North American Indian and Metis people, but rarely caused severe symptoms. The infection occurred less often in white people but was more serious; of 27 cases of toxic respiratory diphtheria, 25 were white people. The public health significance of the endemic infection of the North American Indian and Metis people is discussed.
The effects of spraying on the amounts of airborne foot-and-mouth disease virus present in loose-boxes
Authors: Sellers R. F. , Herniman K. A. J.
Published: October 2009

The air of loose-boxes which had previously held pigs infected with foot-and-mouth disease was sampled for virus after various procedures. Removal of infected pigs led to a 12- to 16-fold reduction in the amount of virus after 5 min. and a 400-fold reduction after 60 min. After heavy spraying (1·2 mm. of water in 5 min.) the amount of virus was reduced 500-fold compared to 30-fold after light spraying (0·20 mm. of water in 5 min.). The partition of infectivity associated with particle size was measured. The partition found after light spraying was similar to that found 5 min. after the pigs had been removed. Heavy spraying brought about a reduction in the infectivity associated with the large particles (> 6 μm.) but had no effect on particles less than 3 μm. A similar partition was found 60 min. after the pigs had been removed. The findings are discussed in relation to the spread of foot-and-mouth disease by the airborne route.
Effectiveness of hand washing and disinfection methods in removing transient bacteria after patient nursing
Authors: Ojajärvi Juhani
Published: October 2009

The effectiveness of various hand washing and disinfection methods in removing transient skin bacteria was studied in hospital after dry or moist contamination of the hands when nursing burn patients. The results were compared with those of laboratory tests with volunteers. A fairly good correlation of the bacterial reductions existed between hospital and laboratory tests. All other methods removedSlaph. aureusfrom the hands more effectively than liquid soap. Gram-negative bacilli were more easily removed than staphylococci, even with soap wash alone.

In hospital, none of the washing and disinfection methods always removed all patient-borne bacteria from the hands. After dry or moist contamination and subsequent washing with soap only, colonies ofStaph. aureuswere often detected in finger-print samples. Staphylococci wero more often completely removed by a 4% chlorhexidine detergent scrub and alcoholic solutions (either with or without previous soap wash) than by liquid soap, hexachlorophene or iodophor preparations. Gram-negative bacilli were more easily removed by all the washing and disinfection methods. After moist contamination, Gram-negative bacilli were more often completely removed from the hands by ethanol than by other treatments.

The results of the present study emphasize the importance of always using gloves when nursing a profuse spreader of bacteria or one who must be protected from infection.
Serial subcultivation of Czechoslovakian and Japanese BCG strains
Authors: Osborn T. W.
Published: October 2009

Changes in the Danish BCG strain under certain regimens of subculture have been shown in preceding studies to be associated with selection of a minority population. Three Czechoslovakian BCG strains, all originally derived from the Danish strain but thereafter and in distinction from it maintained on potato media, have now been investigated. Changes in the immunizing potency of two of these strains have been attributed by other workers to employment of the richer potato media in place of Sauton medium as used for maintenance of the parent Danish strain. However, results from the present study suggest rather that selection of a pre-existing minority genotype or of a now mutant occurred. This proposal is supported by the finding that the third strain has maintained characteristics similar to those of the Danish parent despite many previous transfers on potato media.

Another BCG strain investigated was the Japanese which, like the three Czechoslovakian strains, had been previously maintained on potato media. This strain has been shown in the present study to resemble the Danish strain in supporting a minority population yielding non-spreading colonies. Czechoslovakian vaccine prepared with seed culture supplied from Tokyo has retained characteristics similar to those of the Japanese parent. Although a majority population yielding spreading colonies appears so far to have been retained in both centres, it is considered that selection of the minority could still occur in the course of routine transfer.
Clostridium botulinum in British soil
Authors: Smith G. R. , Young Angela M.
Published: October 2009

Soil samples from various parts of Britain were examined for Clostridium botulinum by a sensitive technique comparable with that recently used for mud samples from British aquatic environments. The results showed beyond doubt that in Britain the prevalence of the organism in soil is much lower than in mud. Of 174 samples from all sites examined only 10 (5·7%) could be shown to contain Cl. botulinum; this finding was consistent with the results of surveys made by less sensitive techniques in 1922, 1928 and 1942. No type other than B was found. The evidence suggested that in certain localized areas the prevalence was likely to be high.

Three sites associated for many years with animals were included in the survey; at the Zoological Society's premises at Regent's Park and at the Market paddocks, Gorgie, Edinburgh, the prevalence of Cl. botulinum was either very low, or nil. In an earlier survey of the redeveloped site of the former Metropolitan Cattle Market, London, 25% of soil samples gave a positive result and no less than four types (B, C, D and E) were demonstrated.
Streptococcal infection in a Junior Detention Centre: a five-year study
Authors: Colling A. , Kerr Ida , Maxted W. R. , Widdowson Jean P.
Published: October 2009

In 1972 more than 20% of boys admitted to a closed community (Junior Detention Centre) developed acute tonsillitis and group-A streptococci were isolated from more than 40% of all boys at some time during their stay of two months. The most common serotype was M-type 5, which has frequently been associated with rheumatic fever in other epidemics; four cases of rheumatic fever occurred between 1972 and 1977. Various methods were tried to eliminate the infection, but only full penicillin prophylaxis (0·25 g oral penicillin 4 times a day for 10 days) to all boys on entry appeared to be effective.

In a sample of cases of acute tonsillitis, group-A haemolytic streptococci were isolated from 31·7% by the use of dry swabs or unenriched transport medium, but with enrichment medium duplicate swabs, 77·0% yielded positive results. We question the current practice in some laboratories of reporting positive cultures only when more than ten colonies of β-haemolytic streptococci are present. In this survey viruses did not appear to be an important cause of acute tonsillitis.

High titres of streptococcal antibodies (antistreptolysin O, anti-desoxyribonuclease B and anti-M associated protein) were found, not only in cases and carriers, but in boys on entry to the centre. This supports epidemiological evidence that adolescent boys on entry to the centre. This supports epidemiological evidence that adolescent boys are particularly prone to streptococcal throat infections.
The evaluation of fabrics in relation to their use as protective garments in nursing and surgery. III. Wet penetration and contact transfer of particles through clothing
Authors: Mackintosh C. A. , Lidwell O. M.
Published: October 2009

A method is described for comparing the resistance to penetration by aqueous fluids, under rubbing contact, of a representative series of fabrics. Untreated woven fabrics are rapidly penetrated, but some non-woven synthetic materials resist penetration for much longer and tightly woven proofed cotton fabrics for prolonged periods, even after repeated washing and sterilizing. If a wetting agent is added to water, penetration occurs more quickly, but fabrics containing natural cotton are penetrated more slowly by serum.

The same fabrics were examined by a test designed to simulate transfer of dry participate material, e.g. skin scales, through them during nursing contact. The proportionate differences observed were much greater than for air dispersal during exercise and closely resembled those obtained by a laboratory rubbing test. In particular, one of the non-woven fabrics showed much greater relative penetration when examined by these methods than the relative dispersal of skin scales through it during exercise.
Outbreak of Legionnaires' disease in Glasgow Royal Infirmary: microbiological aspects
Authors: Timbury M. C. , Donaldson J. R. , McCartney A. C. , Fallon R. J. , Sleigh J. D. , Lyon D. , Orange G. V. , Baird D. R. , Winter J. , Wilson T. S.
Published: October 2009

The bacteriological investigation of an outbreak of Legionnaires' disease in Glasgow Royal Infirmary affecting 16 patients is described. Most of the patients had been treated in high-dependency areas on two floors of the hospital supplied by the same two air-conditioned ventilation systems. The source of infection was traced to contamination of a cooling tower from which a plume of spray discharged into the intake vents of the two ventilation systems. Rubber grommets within the cooling tower probably provided a nidus of infection there. The control and management of the outbreak are discussed: a policy of frankness about the course and progress of the investigations was adopted and helped to allay anxiety on the part of both staff and media.
Apramycin and gentamicin resistance inEscherichia coliand salmonellas isolated from farm animals
Authors: Wray C. , Hedges R. W. , Shannon K. P. , Bradley D. E.
Published: October 2009

Since the aminoglycoside antibiotic apramycin was licensed for veterinary use in 1980, all isolates ofEscherichia coliand salmonellas received at the Central Veterinary Laboratory have been monitored for resistance to apramycin and the related antibiotic gentamicin. During the period 1982–4, the incidence of resistance inE. colito apramycin increased from 0·6% in 1982 to 2·6% in 1984. In salmonellas the incidence of resistance to apramycin increased from 0·1% in 1982 to 1·4% in 1984. Resistance to both apramycin and gentamicin was detected in six different salmonella serotypes, although an isolate ofSalmonella thompsonfrom poultry was resistant to gentamicin but not apramycin. Most of the cultures were isolated from pigs, although the incidence of apramycin resistance inS. typhimurium(DT 204C) from calves has shown a recent dramatic increase. All the isolates with one exception produced the enzyme aminoglycoside 3-N-acetyltransferase IV (ACC(3)IV). The resistance was transferable by conjugation in most of the strains examined, and the plasmids specifying the resistance have been found to belong to a number of different incompatibility groups. Plasmids from threeE. colistrains were compatible with all the reference plasmids and belonged to a previously undescribed group which was investigated further.

It is suggested that bacteria from humans should be examined for resistance to apramycin and gentamicin to determine the possibility of the antibiotic-resistance bacteria, and their genes, spreading from animals to humans.
Capture-ELISA for serum IgM antibody to respiratory syncytial virus
Authors: Cevenini R. , Donati M. , Bertini S. , Moroni A. , Sambri V.
Published: October 2009

A four-component solid-phase capture enzyme immunoassay was set up to test for serum IgM antibody to respiratory syncytial (RS) virus and was compared with immunofluorescence assay (IFA).

A total of 128 young children with acute respiratory infections were studied. Thirty-six were shown to be RS virus-positive by the detection of RS virus in nasopharyngeal secretions and 92 were RS virus-negative. A serum specimen was collected after admission to the hospital (days 0–4) and a further specimen was obtained during days 10–14. Out of 36 RS virus-positive patients, 28 (77·7%) were found to be positive for IgM by both capture-ELISA and IFA. Out of 92 RS virus-negative patients 5 (5·4%) were IgM-positive. Four false-positive results were obtained by IFA due to the presence of rheumatoid factor.

The capture-ELISA was shown to be a reliable technique in detecting specific IgM antibody to RS virus.