bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal comfort zones obtained by two alternative methods: a note
Authors: Wyon D. P. , Andersen I. , Lundqvist G. R.
Published: May 2009

In correspondence arising out of our recent paper (Wyon, Andersen & Lundqvist, 1972), interest has been expressed in the relative widths of the comfort zones obtained by using the Bedford 7-point scale and our proposed dial-vote scale. It was possible to make a direct comparison on our original data, using votes registered simultaneously on the two scales at the end of each hour of exposure. Air temperature rose only slowly towards the end of each hour, and the comparison is probably valid also for steady-state conditions. The proportions voting ‘too hot’ (Bedford categories 6, 7, dial vote >66·6%) and ‘too cold’ (Bedford categories 1, 2, dial vote <33·3%) were derived and probit analysis was performed (Pinney, 1947). Only responses obtained from the 36 female subjects are considered, for very few males were too cold in the temperature range 23–29° C The results are shown in Fig. 1, using the same presentation as in fig. 7 of the original paper. No statistically significant differences could be shown between the pairs of regression lines, either in terms of their slopes or median values. However, the tendency is clearly for the dial-vote method to yield if anything a rather narrower and lower comfort distribution, and hence a narrower zone of comfort, however defined. This in spite of a marked ‘comfort zone’ occupying as much as one-third full scale. As pointed out in our original paper, the comfort zone yielded by either scale should be regarded as a zone of tolerance and not as a zone of ideal comfort.
The effect of saline on the eye irritation caused by swimming-pool water
Authors: Rylander Ragnar , Victorin Katarina , Sörensen Stefan
Published: May 2009

In laboratory experiments the acute eye irritation produced by exposure to tap water was not significantly increased when chlorine compounds were added to the water at concentrations of 1 mg./l. The greatest irritation was produced by 2 mg. Cl2/1. as NH2C1. The addition of NaCl at concentrations above about 0·5% abolished the irritant effect of tap water, and prevented irritation even when 1 mg. Cl2/1. was present.

In a field experiment involving two swimming baths, one with fresh and the other with saline water (0·5 % NaCl), eye irritation in the saline bath was significantly lower than in the freshwater bath only when the swimming time did not exceed 30 min.
Sonne dysentery in day schools and nurseries: an eighteen-year study in Edmonton
Authors: Thomas Mair E. M. , Tillett Hilary E.
Published: May 2009

A study of Sonne dysentery infections in 19 primary and 11 secondary day-schools and 4 day-nurseries has been made over a period of 18 years in an urban area. Measures were taken throughout to try to prevent and control outbreaks. Sonne dysentery was not endemic in the school population and, even at times of high incidence, epidemics were localized within a few of the primary schools, usually in the spring or autumn terms. Incidence rates of Sonne dysentery were highest in primary schools with large infant departments and in nurseries. Secondary schools entirely escaped outbreaks.

The co-operation of head teachers was engaged for all precautionary measures in schools. A policy of immediate exclusion of suspected and infected children was useful in preventing and controlling school epidemics of dysentery. Toilet hygiene was often poor in schools with outbreaks, and this was found to be a profitable field for applying control measures. Infected kitchen workers were only occasionally involved.

Recommendations are given in the light of this study, and some reference is made to the more difficult problem posed by dysentery outbreaks in day-nurseries, where temporary closure may be the best policy. It is important that responsibility for infectious disease control in schools be clearly delineated in the reorganized health services of 1974. Teachers can play an important part in limiting infection.
Nasal immunoglobulin responses in acute rubella determined by the immunofluorescent technique
Authors: Cradock-Watson J. E. , Ridehalgh Margaret K. S. , Bourne M. S. , Vandervelde Eltse M.
Published: May 2009

The indirect immunofluorescent technique has been used to study the specific immunoglobulin responses in nasal secretions from ten adults with acute rubella. Titres of IgA antibody in nasal washings usually exceeded those of IgG, but both types of antibody were detected in all patients. They appeared a few days after the rash, reached maximum titres during the second week and then declined. IgA antibody was no longer detectable after 47 days and was not detected at all in nasal washings from adults who had experienced rubella in the past. Low titres of IgG antibody persisted in some patients for longer than IgA and traces of IgG were found in nasal washings from a minority of adults with a past history of rubella. Nasal antibodies in acute rubella are therefore transient and unlikely to take part in resistance to reinfection.

In sucrose-density gradients nasal IgA antibody sedimented more rapidly than IgG and there was little overlap between these two types of antibody. IgA antibody in serum was more heterogeneous; it was found in nearly all the fractions which contained IgG antibody and in many of those which contained IgM.
Clostridium botulinumin Scottish fish farms and farmed trout
Authors: Burns G. F. , Williams H.
Published: May 2009

Rainbow trout and specimens of pond mud were collected from three fish farms and examined for the presence ofClostridium botulinum.Two of the farms were constructed with concrete channels and one was mud-bottomed.

Cl. botulinumwas isolated only from the mud-bottomed farm (24% of muds), and the isolates were all non-proteolytic type B. The implications of the presence ofCl. botulinumspores in the mud of fish farms is discussed.
Experimental studies on environmental contamination with infected blood during haemodialysis
Authors:   Medical Research Council Working Party
Published: May 2009

To assess the relative importance of different postulated modes of spread of hepatitis B in dialysis units, blood charged with various tracer organisms was used in simulated haemodialysis runs in four laboratories, and the resulting contamination of equipment and environment was measured semi-quantitatively.

Some airborne spread of the tracer organism occurred when tubing containing contaminated blood was needled as the ‘patient’ went on and came off the dialyser. Virtually no small airborne particles could be demonstrated however in simulated emergencies in which a blood line was disconnected, or even when bottles of blood were dropped on to a hard floor from a height of 2 metres.

Bacillus globigii spores from contaminated blood leaked in small numbers into the dialysing fluid through apparently intact coils. T3 phage, with a particle size of the same order as hepatitis B virus, passed in small quantities through the membrane of a Kiil dialyser from blood to dialysing fluid and also in the reverse direction when added to the header tank. A number of other dialysers were also permeable to phage.

Visual assessment of the appropriate moment for inserting the venous line into the ‘patient’ at the onset of dialysis was shown to be unreliable, as the displaced fluid from the end of the venous line was already contaminated before it contained visible red blood cells.

Considerable contamination of exposed surfaces and of the buttons on the proportionating unit cabinet occurred. Minor visible splashing of blood was a commonplace of the laboratory experiments and was shown to be also a common event during routine haemodialysis in two of the dialysis units taking part in the studies.
The immune response to infection with vaccinia virus in mice: I. Infection and the production of antibody neutralizing cell-associated and cell-free virus
Authors: Hutt Lindsey M.
Published: May 2009

The onset, duration and magnitude of antibody responses to a poxvirus infection were examined. Mice were inoculated intravenously with the WR strain of vaccinia virus and developed pocks on their tails. The number of pocks was related to the size of the inoculum. Virus was detectable in the spleen and infected mice were subsequently immune to intravenous and intra-nasal challenge. Sera of infected animals neutralized both cell-free and cell-associated virus. Antibody against cell-free virus appeared first; maximum titres were reached sooner but were lower than those of antibody neutralizing cell-associated virus. Titres remained high for at least 100 days after infection.
Fluid and solid media for isolation of Brucella abortus
Authors: Brodie J. , Sinton G. P.
Published: May 2009

The use of a fluid-enrichment technique increased by 10–16% the recovery rate of Brucella abortus from milks of herds positive to a milk ring test. Three solid media for direct cultural techniques were also tested on the same milks. Combinations of these techniques produced a recovery rate of ca. 88% from MRT-positive-herd milks using a mixture of the centrifuged deposit and cream layer as the inoculum as against a recovery rate of ca. 75% using the MRT cream layer as inoculum. B. abortus biotypes 1–5 and 9 were isolated and growth of all the biotypes was supported by all media used.
The survival of foot-and-mouth disease virus in open air conditions
Authors: Donaldson A. I. , Ferris N. P.
Published: May 2009

The influence of the Open Air Factor (OAF) and daylight on the survival of foot-and-mouth disease (FMD) virus held as captured aerosols on spider micro-threads has been investigated. Virus inactivation due to OAF was slight. Similarly, the effect of daylight on the survival of virus was not marked. The results are discussed in relation to the airborne spread of FMD virus in nature.
Myxomatosis: the virulence of field strains of myxoma virus in a population of wild rabbits (Oryctolagus cuniculus L.) with high resistance to myxomatosis
Authors: Edmonds J. W. , Nolan I. F. , Shepherd Rosamond C. H. , Gocs A.
Published: May 2009

The virulence of field strains of myxoma virus is increasing in the Mallee region of Victoria where the resistance of the rabbit to myxomatosis is high. This suggests that the climax association will be a moderately severe disease.
Field trials of difenacoum against warfarin-resistant infestations of Rattus norvegicus
Authors: Rennison B. D. , Hadler M. R.
Published: May 2009

The anticoagulant difenacoum was tested at two concentrations, 0·005 and 0·01%, in bait against warfarin-resistant rat infestations in farm buildings. Twelve out of the 14 treatments in which the lower concentration of the anticoagulant was used resulted in complete control. One of the remaining two treatments was probably also completely successful, but in the other a few rats, that were not eating the poisoned baits, were still active after 30 days of baiting. All six treatments done using the stronger concentration of poison were completely effective.

Since it took as long to control infestations with 0·01% as with 0·005% difenacoum in treatments carried out under similar conditions, the lower concentration is recommended for use against warfarin-resistant rats.
Airborne infection in a fully air-conditioned hospital: I. Air transfer between rooms
Authors: Foord N. , Lidwell O. M.
Published: May 2009

Measurements have been made of the extent of air exchange between patient rooms in a fully air-conditioned hospital using a tracer-gas method.

When the rooms were ventilated at about six air changes per hour, had an excess airflow through the doorway of about 0.1 m.3/sec. and the temperature difference between rooms and corridor was less than 0.5° C., concentrations of the tracer in rooms close to that in which it was being liberated were 1000-fold less than that in the source room. This ratio fell to about 200-fold in the absence of any excess airflow through the doorways. Considerable dilution took place along the corridors so that the concentration fell by around 10-fold for every 10 m. of corridor.
Airborne infection in a fully air-conditioned hospital: II. Transfer of airborne particles between rooms resulting from the movement of air from one room to another
Authors: Foord N. , Lidwell O. M.
Published: May 2009

Experiments were conducted simultaneously with gas and particle tracers to determine the relative loss of particles between source and recipient sites in the hospital ward units. The magnitude of this loss could be accounted for by the assumption of sedimentation from well-mixed air masses during the time required for movement between source and recipient sites. As a consequence of this loss the degree of isolation between patient rooms for airborne particles was between 4 and 25 times greater than that for gaseous contamination, which reflects the actual transport of air between the rooms.

The design and construction of portable spinning-disk particle generators suitable for field studies is discussed.
Contamination of fluids from a hospital pharmacy
Authors: Joynson D. H. M. , Howells C. H. L. , Liddington R. , Williams A.
Published: May 2009

An investigation into the cause of bacterial contamination of bottles of non-injectable water has been reported. A method of monitoring such bottles has also been described. The roles played by autoclave spray-cooling water and inadequate bottle seals in the contamination of fluids have been examined. Possible methods of reducing the risk of contamination are discussed and the design of an improved method of closure of sterile bottled fluids is stressed. Bacteriological examination is shown to be a more accurate index of the true rate of contamination than measurement of dye concentrations of bottle contents.
The routine serological investigation of cases and contacts of rubella
Authors: Pattison J. R. , Dane D. S.
Published: May 2009

The results of testing sera from 111 patients with rubella-like illnesses and 283 contacts of patients with rubella-like illnesses are described. A sensitive haemagglutination-inhibition test was used in conjunction with fractionation of serum proteins when this was indicated. It was concluded that the testing of serum protein fractions for IgM and IgG rubella antibody greatly increased the effectiveness of laboratory diagnosis. Evidence is presented that during the study period subclinical rubella was relatively uncommon in adults and that the accuracy of clinical diagnosis was high.
An investigation into the potential hazard to animal health of effluent sludge from dairy factories
Authors: Jones P. W. , Bew Janice , Gammack D. B.
Published: May 2009

Sixty-three samples of the more solid material (sludge) separated from the effluent plants of dairy factories were examined for the presence of salmonellas and brucellas. Salmonellas were isolated from two samples (S. heidelberg. [1]; S. indiana [1]). No brucellas were isolated. None of the samples supported the growth of S. dublin. Salmonellas added to effluent sludge at a concentration of 106 organisms/ml, survived less than 70 days.

The sludge from dairy factory effluent plants does not appear to be a source for the spread of salmonellosis or brucellosis.
An investigation of the possible transmission of rhinovirus colds through indirect contact
Authors: Reed Sylvia E.
Published: May 2009

Rhinovirus was recovered from the fingers of 16 of 38 volunteers and others, who were swabbed during the acute stages of their colds. Very low titres of virus were also recovered from 6 of 40 objects recently handled by infected volunteers, but not from the fingers of 18 non-infected subjects whose flat-mates were shedding virus. When rhinovirus from nasal secretions was dried on skin or other surfaces during laboratory experiments, approximately 40–99 % of infectivity was lost. Virus could be transferred from surface to surface by rubbing, the transfer being more efficient if it was carried out while the inoculum was still damp.

Volunteers could infect themselves if a moderately heavy dose (88 TCD50) of virus was inoculated on the finger and then rubbed into the conjunctiva or nostril, especially if the inoculum was still damp. From estimates of virus titres in nasal washings and on fingers, and of amounts transferred by rubbing, it was concluded that spread of colds is unlikely to occur via objects contaminated by the hands of the virus-shedder, but that a recipient might pick up enough virus on his fingers by direct contact with heavily infected skin or secretions to constitute a risk of self-inoculation via the conjunctiva or nostril.
Bunyavirus isolations from mosquitoes in the western Canadian Arctic
Authors: McLean D. M. , Grass P. N. , Judd B. D. , Ligate L. V. , Peter K. K.
Published: May 2009

Strains of California encephalitis virus (snowshoe hare subtype) were isolated from 8 of 475 pools comprising 23747 unengorged female mosquitoes of five species collected at three of six locations throughout the Mackenzie Valley of the Northwest Territories, Canada, from latitudes 60 to 69° N between 10 and 24 July 1976. Minimum field infection rates included 1:2734 forAedes communis, 1:256 to 1:3662 forA. hexodontusand 1:911 to 1:1611 forA. punctor.Northway virus was also isolated from 1 of 3662A. hexodontusmosquitoes collected at Inuvik (69° N, 135° W). Transmission of CE virus byA. communisinfected by feeding on virus in defibrinated blood and incubation at 0, 13 and 23 °C for 13–20 days clearly demonstrates the importance of this species as a natural vector, and transmission of CE virus byCuliseta inornataafter incubation at 0 and 13 °C following intrathoracic injection strengthens evidence of its role as a natural vector. Immunofiuorescence was less reliable than imunoperoxidase for detection of CE viral antigen in mosquito salivary glands.
Travellers' diarrhoea: does it occur in the United Kingdom?
Authors: Freedman B. J.
Published: May 2009

Of 485 persons who replied to a questionnaire after attending a European Congress in September 1974, diarrhoea was experienced by 4 of 143 British residents and 2 of 342 visitors to the United Kingdom. This extremely low incidence of travellers' diarrhoea contrasts with the high incidence reported in travellers from countries with cool climates and north European standards of hygiene to countries where these conditions do not hold.
The laboratory surveillance of influenza epidemics in the United Kingdom 1968–1976
Authors: Pereira Marguerite S. , Chakraverty Pratima
Published: May 2009

The extensive laboratory investigations of respiratory disease in the U.K. over many years have demonstrated the frequency with which influenza viruses, both A and B, are found each winter. Only rarely are none isolated.

These findings correlate well with other indicators of influenza such as increases in sickness benefit claims and in deaths attributed to influenza and pneumonia.

However, outside these demonstrable peaks of incidence influenza viruses have been found to circulate over considerably longer periods often first appearing as early as November and continuing through to April or even May. But there has been no regular or predictablepattern determined.

The period of 1968–76 has seen a series of differently developing influenza winter epidemics caused by a series of the H3N2 virus. The contributions of virus isolation and serology to influenza surveillance is discussed.
Failure of hand disinfection with frequent hand washing: a need for prolonged field studies
Authors: Ojajärvi Juhani , Mäkelä Paavo , Rantasalo Ilari
Published: May 2009

In a prolonged field trial a 4% chlorhexidine digluconate detergent scrub (HibiscrubR), that had earlier proved to be an effective hand disinfectant, was studied in hospital wards. Finger tips were found to harbour more bacteria than the hand dorsum and the samples collected from them yielded more information on the bacteriological and dermatological effects of hand disinfectants in practice.

In wards with a relatively low hand-washing frequency (less than 20 times in 8 hours) the bacteriological results resembled those obtained by in-use tests with volunteers. In the neonatal unit where the hand washing frequency was remarkably high, even occasionally over 100 times/8 h shift, an increase in the bacterial colony counts of the majority of the staff was recorded both before and after hand washing already after using the preparation for 1 week. Age, occupation and hand-washing frequency all correlated with the bacteriological results. Twenty-seven out of 37 persons complained of side effects such as wounds of finger tips and redness or heavy drying of the skin. Wounds, particularly on finger tips, resulted in the failure of disinfection. An increase in bacterial counts was sometimes noted without any dermatological or subjective changes. Drying of the skin was complained of less often when no increase in skin bacteria occurred.

After the changeover of washing practice to a detergent followed by a rinse with spirit solution containing chlorhexidine and glycerol a decrease was recorded in the bacterial counts. It is concluded that more attention should be paid to long-term testing of hand washing and disinfection methods to ensure optimum final results in practice. It is obvious that the knowledge obtained from short time in-use testing cannot be applied to all conditions of use.
Air exchange through doorways. The effect of temperature difference, turbulence and ventilation flow
Authors: Lidwell O. M.
Published: May 2009

Analytical expressions have been derived for the exchange of air across doorways or similar apertures, in terms of the temperature difference between the spaces on both sides of the opening and the net volume of air flowing through this as a result of unbalanced air supply or extract. A simple allowance for turbulence which gives reasonable correspondence with observation is included. The formulae, which assume complete air mixing on both sides of the doorway up to the plane of the aperture, predict outflows from the warmer side, when there is an excess air supply to this side, which are progressively smaller than those observed as the temperature difference rises above 2–3 °C and the volume of excess air supply increases to produce an averaged outflow velocity greater than 0·1–0·15m/s. This seems to be due to lack of mixing of the warm outflowing air with the cooler air mass. A correction factor for this can be deduced as a function of the pressure difference due to the excess air supply. The limiting magnitude and general form of this function are compatible with a simple theoretical model of the air flow patterns involved.
Myxomatosis on the Western Plains of Victoria
Authors: Tighe F. G. , Edmonds J. W. , Nolan I. F. , Shepherd Rosamond C. H. , Gocs A.
Published: May 2009

Myxomatosis on the Western Plains is an enzootic disease in contrast with the epizootic pattern which is general in eastern Australia. The most unusual aspects are the presence of significant numbers of diseased rabbits throughout the winter and the continuously low percentage of rabbits with antibodies to myxoma virus.

Climatic and topographic conditions are unsuited to the production of the high densities of mosquitoes necessary for widespread epizootics. Under these conditions the effects of less efficient methods of myxomatosis transmission are apparent. The unusual epidemiology of myxomatosis has resulted in selection for virulence of the virus similar to that which has occurred under summer epizootic conditions. All field strains are now in the mid range of virulence.
Serological studies ofBacteroides fragilis
Authors: Elhag K. M. , Bettelheim K. A. , Tabaqchali Soad
Published: May 2009

Using direct agglutination methods, a simple serological scheme for the classification ofBacteroides fragilisis described. Twenty strains ofB. fragiliswere selected by a process of successive screening from 151 strains obtained from various sources. O-antigens were prepared from the 20 strains, and used to raise antisera in rabbits.

Each of the 20 antisera reacted with its homologous antigen and eight antisera cross-reacted with other subspecies. These cross-reactions were successfully removed after absorption of the antisera with the cross-reacting antigens, resulting in 19 type-specific antisera, titres ranging from 40 to 320, and 19 distinct serotypes ofB. fragilis. There was no correlation between the antigenic and the biochemical characteristics of these strains and no cross-reactions occurred with other gram-negative anaerobes,B. melaninogenicus, Sphaerophorus necrophorusandFuso-bacterium necrogenes.
Corynebacterium haemolyticum infections in Cambridgeshire
Authors: Fell H. W. K. , Nagington J. , Naylor G. R. E. , Olds R. J.
Published: May 2009

In the Cambridge area, 143 patients infected with Corynebacterium haemolyticum were found during the period May 1967 to December 1974. The pharynx was the commonest site of infection and 100 of the 137 pharyngeal infections were in patients aged between 15 and 25 years. Such patients usually had a sore throat; about half of them also had a maculopapular rash. The organism and the clinical features which we have come to regard as typical of this infection are briefly described.
The in vitro drug resistance of Salmonella dublin isolated from cattle
Authors: Hinton M. , Williams B. M.
Published: May 2009

The resistance of Salmonella dublin to eight antibacterial drugs was assessed wider diagnostic laboratory conditions. Two techniques were used consecutively and the differences in the results are described. Strains of S. dublin isolated from either calves, adult cattle or abortion material showed no differences in resistance for either of the techniques, though differences between the two techniques were found.
Microbiological evaluation of South Australian rock lobster meat
Authors: Yap A. S. J.
Published: May 2009

Samples of frozen precooked rock lobster meat from five South Australian fish-processing plants situated in the West Coast and south-east regions were tested over a period of six months during the 1974/5 lobster fishing season. The most probable number (MPN) ofE. coliand coliforms,Staphylococcus aureusandSalmonella, as well as total plate count (TPC) were determined in 480 samples. Monthly geometric mean TPC ranged from 1600/g to 25,000/g. The highest geometric mean of the MPN of coliforms andE. coliwere 4·9/g and 1·8/g respectively. The highest geometric mean number of staphylococci was 18·6/g.Salmonellawas not detected in the 480 units tested. Only 0·4% of the samples had TPC exceeding 100,000/g. Coliforms andE. coliwere not present in 76·1% and 92·7% respectively of the samples tested.Staphylococcus aureuswas not detected in 67·7% of the samples. The numbers of organisms in 82% of the samples fall within the microbiological standards proposed by the National Health and Medical Research Council of Australia for frozen precooked foods. The results of this study demonstrate the microbial quality of precooked lobster meat attainable when good manufacturing practices are used.
The potential for contamination of intravenous infusions by airborne skin scales
Authors: Holmes C. J. , Allwood M. C.
Published: May 2009

Skin scales may be attracted onto the surface of administration set connector needles before insertion into infusion containers. Viable microorganisms associated with skin scales may therefore gain access to the infusion by this route. A technique is described for creating an environment of airborne skin scales. This environment is used to examine the attraction of skin scales onto the surface of administration set connector needles and three other materials. After exposure, skin scales are found adhering to the surface of each material examined. The attraction of skin scales onto administration set connector needles is dependent on the time of exposure to the environment. Results suggest that intravenous infusions can be contaminated by this route when the infusion and administration set is assembled.
Dose-response relationships in a microneutralization test for foot-and-mouth disease viruses
Authors: Booth J. C. , Rweyemamu M. M. , Pay T. W. F.
Published: May 2009

Two-dimensional quantal microneutralization tests on foot-and-mouth disease viruses, in which neutralizing antibody activity was titrated against a serial range of virus doses, demonstrated a variety of dose-response curves some of which were rectilinear, others clearly curvilinear. Moreover, in the case of the non-linear responses obtained with some antisera, the shape of the curve was such that antibody titres recorded with doses of virus ranging from 103–105TCD 50 were closely similar. Studies were carried out on the effect of varying the conditions of the test on the shape of the dose-response curve: significant differences were obtained after treatment of the antiserum–virus mixtures with anti-species globulin, and when the test was assayed in cells of differing susceptibility to infection.
Bacterial contamination in a modern operating suite, 2. Effect of a zoning system on contamination of floors and other surfaces
Authors: Hambraeus A. , Bengtsson S. , Laurell G.
Published: May 2009

In this investigation the bacterial contamination of surfaces such as walls and floors in a modern operating suite, together with surfaces of lamps in the operating theatres, and the clogs worn by staff, was studied. Counts of colony-forming units were made on impression plates containing blood-agar with Tween 80 for total bacterial counts, Baird Parker medium with egg yolk and tellurite for Staphylococcus aureus and trypticase peptone agar with neomycin and polymyxin for Clostridium spp.

The areas examined were divided into the patients' route to the operating theatre, the staff's route, and the central area containing the operating rooms, anaesthetic rooms, and exit and scrub-up areas. In the patients' route counts of total organisms ranged from about 10 000 to 30 000/m2 for Staph. aureus the range was from 70 to 540/m2. In the staff's route the highest count was about 70000/m2 in the dressing area, and the numbers of Staph. aureus were about the same as along the patients' route. In the inner zone the counts were somewhat lower for both total organisms and Staph. aureus. Total counts on the floor from all areas of the inner zone were significantly higher just before the second operation than before the first operation on the same day. The total and Staph. aureus counts on walls, floors and lamps were the same after clean operations as after operations classified as ‘contaminated’ or ‘dirty’.
Genetics of warfarin-resistance in house mice of three separate localities
Authors: MacSwiney Felicity J. , Wallace Margaret E.
Published: May 2009

Mice from Loughborough and Nottingham were obtained in order to compare the inheritance of warfarin resistance in these populations with that established for a Cambridge population (Wallace & MacSwiney, 1976). Using the same breeding programme and warfarin testing technique, it is established that resistance in the new areas is, as in the Cambridge area, controlled by the major resistance gene, War, in chromosome 7, with penetrance affected by sex and modifiers. In addition, survival differences in males of different ages strongly suggests that War + has less penetrance with age. Penetrance differences between the experiments establishes that wild populations differ in their modifier complex and that more than one modifier, probably several, exist. Questions are posed as to the adaptive significance of the phenomena, and the way in which they work, in the patchwork of warfarin baited and unbaited areas in this country.
Observations of the effects of formaldehyde on cockroaches and their flora: III. The effect of formaldehyde in eliminating the normal gut flora
Authors: Bartzokas C. A. , McCarthy K. , Baker B. F. , Graham R.
Published: May 2009

The normal flora of cockroaches (Periplaneta americana) was determined over a period of 24 days prior to substituting water with 1% Formalin for drinking water. During the first 4 days of treatment the normal flora was significantly reduced and by the fifth day, when the cockroaches became diarrhoeic, no bacteria, fungi, or viruses could be detected by the methods used.
Poliomyelitis surveillance in England and Wales, 1969–1975
Authors: Smith J. W. G. , Wherry P. J.
Published: May 2009

Poliomyelitis continued to be a rare disease in England and Wales in the period 1969–75. Only 31 paralytic and 44 cases of possible non-paralytic poliomyelitis were recorded during the 7 years.

Of the 31 paralytic cases approximately one third were vaccine-associated; 3 were patients who had recently received oral poliovaccine and 7 had been in contact with a vaccinated person. Five of these 7 patients were parents of recently vaccinated children. The rate of vaccine-associated poliomyelitis was estimated in recipients to be 0·2 and in contacts 0·4 per million doses of vaccine given.

Marker test results were reported on 555 strains of poliomyelitis virus isolated during 1969–75, using the reproductive capacity temperature test. Forty-eight (8·6%) resembled wild virus in this property, 15 strains being type 1, 8 type 2 and 25 type 3. Most of these isolations of apparently wild virus were from excreters with no symptoms of poliomyelitis, although 3 of the 15 type 1 strains were from patients with paralytic poliomyelitis and 3 from possible cases of non-paralytic poliomyelitis. None of the 8 apparently wild type 2 viruses was from a case of paralytic illness and only 1 of the 39 type 3 strains.

Eleven of the 31 paralytic cases were in patients in whom the infection was likely to have been acquired abroad.
Genetic factors in leprosy: a study of children in Uganda
Authors: White Susan J. , Stone M. Mary , Howland C.
Published: May 2009

A group of 20 990 children in Uganda was examined for leprosy over a period of 8 years. There was no evidence that the incidence of leprosy varied according to a child's genetic relationship to a leprosy patient, once allowance had been made for the grade of physical contact.
The effect of antimicrobial feed additives on the colonization of the alimentary tract of chickens by Salmonella typhimurium
Authors: Smith H. Williams , Tucker J. F.
Published: May 2009

Groups of 33 chickens were fed continuously on diets containing feed additives that are employed commercially for a variety of purposes, and were infected orally when 4 days old with a nalidixic acid-resistant mutant of Salmonella typhimurium. The amount of S. typhimurium organisms excreted in their faeces was estimated by culturing them at intervals and in a standard manner on brilliant green agar containing sodium nalidixate; when the chickens were killed their caecal contents were examined by the same technique.

Avoparcin and lincomycin, like nitrovin and tylosin (Smith & Tucker, 1975b), favoured colonization of the alimentary tract by the S. typhimurium organisms as shown by the fact that the chickens to which they were fed excreted these organisms in their faeces in higher concentration and for longer periods of time than did chickens fed on non-medicated diets. Amprolium, monensin, dimetridazole, arsenilic acid and nitro-hydroxyphenylarsonate had no obvious effect on the salmonella excretion pattern.

When only five chickens in each group were experimentally infected so that the effect of the feed additives on infections acquired by contact could be monitored, avoparcin, lincomycin, nitrovin and tylosin again favoured colonization of the alimentary tract with the S. typhimurium organisms and so did dimetridazole. Arsenilic acid, in contrast, hindered the development of infection. Amprolium, monensin and nitro-hydroxyphenylarsonate were without obvious effect.

Many of the chickens that were fed on diets that favoured S. typhimurium colonization, but not those fed on non-medicated diets, were still excreting S. typhimurium organisms in their faeces when they were killed at 56 days of age, the age at which broiler chickens kept under commercial conditions are usually slaughtered.
Prevalence ofBacillus cereusin the faeces of healthy adults
Authors: Grosh A. C.
Published: May 2009

In a survey designed to determine the prevalence ofBacillus cereusin the faeces of healthy persons, the organism was found in low numbers in 100 (14%) of single faecal specimens from 711 adults in the general population. In addition, in an attempt at assessing the changes in theB. cereusdistribution within the faecal flora of the individual, weekly faecal specimens were submitted over a seven-week period by 18 members of staff of two laboratories. The total isolation rate was again 14%, with 15 serotypes represented. In four individualsB. cereuswas isolated in two consecutive weeks and in all cases the isolates were of different serotypes. Excretion was never recorded for more than two consecutive weeks. These findings probably reflect the intake ofB. cereusin the individual's diet.
Isolation and cultivation of bovine ephemeral fever virus in chickens and chicken embryos
Authors: Elamin M. A. Gaffar , Spradbrow P. B.
Published: May 2009

Unadapted bovine ephemeral fever (BEF) virus was isolated from cattle blood after intravenous inoculation into chicken embryos. Infected embryos died or hatched as abnormal chickens. The chick embryo was slightly less sensitive to unadapted BEF virus than were Vero cell cultures, but the use of embryos avoids the several blind passages that are required to isolate BEF virus in unweaned mice. Chick embryos were considerably less efficient than Vero cell culture or unweaned mice in detecting Vero cell-adapted and mouse-adapted BEF virus respectively.

Viraemia was demonstrated in chicken embryos at 1–4 days and in one-day-old chickens at 1–3 days after intravenous inoculation of BEF virus. BEF virus was demonstrated by isolation and by immunofluoresence in heart, brain, lung and liver of chicken embryos at 1–5 days and in lung and liver of one-day-old chickens at 1–2 days, after intravenous inoculation. The isolated viruses were confirmed as BEF virus by neutralization with immune mouse ascitic fluid. BEF neutralizing antibodies were produced in 4-week-old and adult chickens after intravenous inoculation with BEF virus.
The serology of experimental Salmonella dublin infections of cattle
Authors: Hall G. A. , Jones P. W. , Aitken Maureen M. , Parsons K. R.
Published: May 2009

Agglutinating antibodies to somatic ‘O’ and flagellar ‘H’ antigens of S. dublin were measured in the serum of 43 pregnant heifers before intravenous or oral infection with S. dublin and in the serum of 21 uninfected control animals. The data from these animals were analysed statistically and a titre of 1/80, to both antigens, has been interpreted as of doubtful significance and a titre of 1/160 to both antigens, has been interpreted as significantly raised. Animals in which fetal infection occurred after challenge by either the intravenous or oral route developed significant increases in ‘H‘O’ titres indicating the value of measuring ‘H’ titres in the diagnosis of S. dublin abortion. In animals which were infected orally and in which infection appeared to be confined to the alimentary tract the ‘H’ titre did not become significantly raised. Lack of correlation between antibody titres and faecal excretion of S. dublin and persistence of infection in carcasses confirms that the serum agglutination test is of no value in detecting latent carriers.
Shedding of bacteria and skin squames after handwashing
Authors: Meers P. B. , Yeo Gillian A.
Published: May 2009

Particles released into the air by wringing the hands together were collected in a slit sampler before and after washing with bar soap, with three surgical scrubs, and after rubbing them with a spirit-based lotion. The particles were identified, their number estimated, those that bore bacteria counted, and the bacteria themselves classified. It was found that there was a significant increase, averaging 17-fold, in the number of particles carrying viable bacteria released after washing with soap. The increase in bacterial dissemination was suppressed if a surgical scrub was used in place of soap, or when the lotion was used without washing. The number of skin squames released increased by 18-fold or more after washing with soap or a surgical scrub, but not after using the lotion. This suggests that a surgical scrub should be used more widely in clinical practice, and that a spirit-based hand lotion might with advantage become a partial substitute for handwashing, particularly in areas where handwashing is frequent and iatrogenic coagulasenegative staphylococcal infection common.
Antibiotic resistant staphylococci acquired during the first year of life
Authors: Burr M. L. , Howells C. H. L. , Rees P. W. J.
Published: May 2009

Nasal swabs were taken from 492 babies born consecutively to residents of two South Wales towns soon after their discharge from maternity hospitals. Staphylococcus aureus was isolated from 352 babies (72%) and in 79 (22%) of these it was resistant to at least one antibiotic. By the time these babies were a year old the prevalence of both sensitive and resistant strains had fallen, so that only 12% still carried nasal staphylococci, but 64% of these organisms were then resistant to penicillin. Administration of penicillin to the baby seemed to be a more important factor in selecting resistant organisms than other antibiotics given to the baby, any antibiotic treatment to other members of the household, or discharge from hospital.
Enumeration of micro-organisms in food: a comparative study of five methods
Authors: Kramer J. M. , Gilbert R. J.
Published: May 2009

Five methods for the enumeration of micro-organisms in food (pour plate, surface spread plate, surface drop, agar droplet, and microdilution) were used in parallel to examine 100 samples selected from a wide range of food products.

Statistical analyses of the results showed that the regression and correlation coefficients between the methods were highly significant; the lowest correlation coefficient derived for any pair of methods was 0·979. A variation in count between the methods of less than 0·5 log10cycles was given by 98% of the samples.

Analysis of the operation times and material requirements of each method showed that substantial savings in cost, time, space and support labour were achieved with the microdilution and agar droplet techniques as compared with the conventional pour plate and spread plate methods.
Bacteriological evaluation of a mobile laminar cross-flow unit for surgery, under laboratory circumstances
Authors: van der Waaij D. , Wiegersma N. , Dankert J.
Published: May 2009

A mobile laminar cross-flow unit for surgery has been evaluated by the use of an experimental bacterial aerosol of Escherichia coli in different concentrations, generated at several different sites. A separate ventilation system, mounted underneath the table, produced an almost downward directed curtain of sterile air along both sides of the table. When the velocity of the air stream, discharged by the cross-flow unit, was adjusted at 0·50 m./sec. at 2 m. from the filter face (at the head end of the operation table), the surface of the table could be maintained free of bacterial settling, even after aerosolization of heavily concentrated suspensions of 108 bacteria/ml. at different sites outside the enclosure and underneath the table as well.
The antibacterial activity of chloroxylenol in combination with ethylenediaminetetra-acetic acid
Authors: Dankert J. , Schut I. K.
Published: May 2009

The bactericidal activity of RBA 777 has been found to vary with both the cultural and environmental test conditions againstPseudomonas aeruginosaand to a lesser extent againstStaphylococcus aureus.These variations may explain certain anomalies in earlier work regarding the activity of chloroxylenol-based products. The addition of EDTA to RBA 777 has brought about an improvement in the performance againstP. aeruginosaand this activity is confirmedin vivo.Previous reports have already illustrated this potential and the evaluations of the new antibacterial agent DA 136 confirms and extends these results to its performance under adverse conditions, often associated with the hospital environment.
Specific immunoglobulins in infants with the congenital rubella syndrome
Authors: Cradock-Watson J. E. , Ridehalgh Margaret K. S. , Chantler Shireen
Published: May 2009

The indirect immunofluorescent technique has been used to detect and titrate the specific immunoglobulins in serum specimens from 154 infants with confirmed or suspected congenital rubella. IgM antibody was stained more efficiently in sucrose density gradient fractions than in whole serum and was detected in this way in 27 out of 40 patients with confirmed congenital rubella at ages ranging from birth to 2 years. It was present in 48 out of 50 serum specimens during the first 6 months of life and in 11 out of 38 specimens obtained at ages between 6½ months and 2 years. IgM antibody was therefore estimated to persist for about 6 months in the majority of cases and up to 2 years in a few individuals. IgM antibody was also detected by this method in 11 out of 114 infants with suspected but unconfirmed congenital rubella at ages up to 5 months. The total concentrations of IgM were above the normal range in nearly all sera taken from confirmed cases during the first 3 months of life and in half the specimens obtained between the ages of 3 and 6 months.

IgG antibody was detected by fluorescent staining of whole serum in all patients with congenital rubella. Geometric mean titres increased during the first 3 months of life and then declined slowly. IgA antibody was not detected, except in two patients in whom traces were present at the age of 6 months, and the total concentrations of IgA were usually within normal limits.

Fluorescent staining of fractions showed that the sedimentation characteristics of rubella IgG and IgM antibodies were the same in infants as in adults. The peak IgM fractions never contained IgG antibody, and the presence of specific IgM in these fractions could usually have been safely inferred from their HAI titres. Fluorescent staining, however, was more sensitive and frequently detected IgM antibody in fractions which had no definite HAI activity.

Fluorescent staining of whole serum for IgM antibody was less distinct, and often unsuccessful, even in specimens in which specific IgM was detected in the fractions. The addition of IgG- to IgM-containing fractions caused depression of IgM staining and suggested that failure to detect IgM antibody in whole serum was partly due to competitive inhibition by specific IgG.
The behaviour of porcine cytomegalovirus in commercial pig herds
Authors: Plowright W. , Edington N. , Watt R. G.
Published: May 2009

A longitudinal, virological and serological study of pigs in two herds with respiratory disease showed that infection by porcine cytomegalovirus (PCMV) was universal in both.

Virus excretion usually began when piglets were between 3 and 6 weeks of age and reached a maximum between 5 and 8 weeks; it was usually no longer detectable at 11–12 weeks. Antibody demonstrable in indirect immunofluorescence (IIF) tests was present to moderate or high titre in all piglets at 2–3 weeks. This was presumed to be maternal in origin as it declined in titre between 2–3 and 5–6 weeks. After this fall the majority of piglets showed seroconversion as a result of virus infection. One group of 12 pigs in which infection occurred earlier than usual showed a very poor antibody response, which, nevertheless, persisted through to week 27.

The findings are discussed with relation to porcine atrophic rhinitis and cytomegalovirus infection in other species.