scholarly journals Observations on the distribution ofStaphylococcus aureusin the atmosphere of a surgical ward

1962 ◽  
Vol 60 (3) ◽  
pp. 387-400 ◽  
Author(s):  
Phyllis M. Rountree ◽  
Mary A. Beard
Keyword(s):  
Technical Assistance ◽  
Medical Research Council ◽  
Contamination Rate ◽  
Staph Aureus ◽  
Large Numbers ◽  
Surgical Ward ◽  
Nasal Swabs ◽  
High Contamination Rate ◽  
Predominant Strain ◽  
Number Of Bacteria

The environment of two contiguous surgical wards was examined over a period of twelve months by means of a slit sampler, settle plates and blanket sweep plates. At the same time, nasal swabs were taken each week from the patients and all cases of sepsis examined bacteriologically.Phage typing of more than 3600 isolations ofStaph. aureusshowed that there was one predominant strain in the air, bedding, patients' noses and infected wounds.There was no relationship between the total number of bacteria in the ward air and the numbers ofStaph. aureus.The recovery of large numbers ofStaph. aureusfrom the air at certain periods was associated with a high contamination rate in the blankets and with an increased incidence of staphylococcal sepsis.Not all nasal carriers ofStaph. aureuscontaminated their bedding. There was evidence that some patients became nasal carriers of strains of staphylococci previously isolated from their bedding.Some evidence was obtained that blankets may play a role in the transmission of staphylococci from patient to patient.This work was supported by a grant from the Australian National Health and Medical Research Council. Our thanks are due to Mrs Elisabeth Bradshaw for her technical assistance and to Prof. John Loewenthal for his interest and for permission to study his wards.

Identification of Staphylococcus aureus from enriched nasal swabs within 24 h is improved with use of multiple culture media

2013 ◽  
Vol 62 (9) ◽  
pp. 1365-1367 ◽  
Author(s):  
Maya Nadimpalli ◽  
Christopher Heaney ◽  
Jill R. Stewart
Keyword(s):  
Staphylococcus Aureus ◽  
Culture Media ◽  
Nasal Carriage ◽  
Healthy Population ◽  
Staph Aureus ◽  
Nasal Swabs

Nasal carriage of Staphylococcus aureus is commonly evaluated via culture-based methods. We found that parallel use of two media, Baird-Parker and CHROMagar™ Staph aureus, increased detection of S. aureus from a healthy population by 29 %. We suggest use of both media for optimal identification of S. aureus from healthy cohorts.

Neurosecretory granules in the infective stage of Haemonchus contortus

Parasitology ◽  
1968 ◽  
Vol 58 (3) ◽  
pp. 657-662 ◽  
Author(s):  
W. P. Rogers
Keyword(s):  
Technical Assistance ◽  
Public Health Service ◽  
Special Role ◽  
Public Health Service Grant ◽  
Posterior Edge ◽  
Anterior Border ◽  
Dense Bodies ◽  
Large Numbers ◽  
Light Region ◽  
Light Area

Large numbers of electron-dense bodies, 700–1900 Å in diameter, usually seen each with its own limiting membrane, were found in axons of the ventral nerve of infective juveniles of H. contortus. Axons containing these granules merged, without limiting membranes, with a ‘light’, diffusely granular region, about 1·5–2 μm3. The ‘light’ area also merged without boundaries with the underlying cuticle which was different from the surrounding cuticle. This modified cuticle, of which the anterior border lies about 1·3 μm from the posterior edge of the excretory pore, extends slightly beyond the ‘light’ area. Otherwise it is a useful topographical marker for the extent of the ‘light’ area.It is considered that the ‘light’ region has a special role in the physiology of the cuticle.I wish to thank Mrs M. Ross for expert technical assistance and Mr R. I. Sommerville for valuable advice. This work was supported by a U.S. Public Health Service Grant, AI 04093–05. The use of the Siemens electron microscope was made possible by a grant from the Australian Research Grants Committee. Financial help from Parke, Davis and Co. (Australia) is also gratefully acknowledged.

Distribution of the nematode Labiostrongylus longispicularis (Wood) within the stomach of the Red Kangaroo Megaleia rufa (Desmarest)

Parasitology ◽  
1965 ◽  
Vol 55 (3) ◽  
pp. 543-550 ◽  
Author(s):  
M. L. Dudzinski ◽  
R. Mykytowycz
Keyword(s):  
Technical Assistance ◽  
Female Worm ◽  
Sample Material ◽  
Quadratic Regression ◽  
Red Kangaroo ◽  
Large Numbers ◽  
Cardiac Region ◽  
The Mean ◽  
Two Stages ◽  
The University

The distribution of two stages of the nematode Labiostrongylus longispicularis (Wood) in thirty-eight stomachs of the Red Kangaroo, Megaleia rufa (Desmarest) has been analysed statistically.A quadratic regression was used where y = log of mean worm densities of stomach sections + 1 and x = numerical values of the mid-positions of the sections. The analysis revealed significant maxima in the proximity of the cardiac region. The maxima in stomachs with relatively large numbers of worms were found to be further away from the pylorus than in the stomachs with small numbers of worms. The mean maximum densities were about fifty worms per 100 g of stomach content in highly infected animals and about eight in low infections. It is suggested that freshly chewed food or saliva may be a factor regulating the distribution of worms.The parasite was absent from the stomach's pyloric region where the pH is low.Sex and size of the worm were independent of its position in the stomach.The average number of eggs per adult female in the different stomach sections roughly corresponded to the density of worms in these sections, but the sample material was inadequate to show that this relationship was statistically significant.The mean number of fertilized eggs per female worm was 3300.Thanks are due to Professor E. J. Williams of the University of Melbourne and Mr B. V. Fennessy of the Division of Wildlife Research, C.S.I.R.O., for reading and criticizing the manuscript, and to Messrs E. R. Hesterman and C. Kogon for technical assistance.

scholarly journals STUDIES UPON EXPERIMENTAL PNEUMONIA IN RABBITS

1913 ◽  
Vol 18 (1) ◽  
pp. 50-60 ◽  
Author(s):  
B. S. Kline ◽  
M. C. Winternitz
Keyword(s):  
Chemical Substance ◽  
Repeated Injection ◽  
Experimental Pneumonia ◽  
Large Numbers ◽  
Similar Chemical ◽  
Small Doses ◽  
Number Of Bacteria

1. The importance of the leucocyte in the resistance of animals to experimental pneumonia is emphasized by the fact that animals treated with benzol, a leucotoxic substance, rapidly succumb to the disease, while animals treated in like manner with toluol, a very similar chemical substance causing no leucopenia, show no decreased resistance. 2. The rôle of the leucocyte in the resistance of animals to experimental pneumonia is further emphasized by the fact that animals that respond to the pneumococcus infection with a leucocytosis, as occurs after the repeated injection of toluol, are more resistant to the pneumonia. Further, the hyperleucocytosis produced by repeated injection of nutrose before the production of pneumonia likewise seems to increase the resistance of the animals. 3. Experimental pneumonia is not necessarily fatal in rabbits. The factors determining the outcome of the disease are numerous; among these is the number of bacteria inoculated. Animals receiving small doses usually survive, while those receiving comparatively large numbers usually succumb.

scholarly journals Incidence and importance of streptococci in an institution for rheumatic children

1953 ◽  
Vol 51 (2) ◽  
pp. 157-161 ◽  
Author(s):  
S. A. Doxiadis ◽  
Sheila M. Stewart
Keyword(s):  
Direct Evidence ◽  
Medical Research Council ◽  
Cross Infection ◽  
Number Of Children ◽  
Erythrocyte Sedimentation ◽  
Laboratory Facilities ◽  
Nasal Swabs ◽  
Group A ◽  
Low Incidence ◽  
Hospital School

1. The incidence of haemolytic streptococci in the patients of a Hospital School for rheumatic children was determined over a period of 1 year.2. In the total of 1644 throat and 1644 nasal swabs, group A strains were isolated from 20 throat and two nasal swabs. Eighty-seven strains of Lancefield's groups C and G and 54 strains of groups other than A, C, or G were isolated3. There was no evidence of cross-infection.4. Factors contributing to the low incidence of group A strains and the absence of cross-infection are discussed.5. The carriage of groups C and G strains did not appreciably affect the erythrocyte sedimentation rate.6. Although no direct evidence is available, the experience of the present study suggests that the incidence of streptococci in an institution for rheumatic children may be reduced by: (a) bacteriological screening before admission; (b) regular swabbing and Lancefield's grouping of streptococci isolated for the early detection of group A strains; and (c) administration of penicillin or sulphadiazine prophylactically to even a limited number of children.We thank Prof. R. S. Illingworth for his advice in the writing of this paper, Dr J. L. Emery for laboratory facilities, Dr R. E. O. Williams for his advice in the planning of the investigation, and the matron and sisters of Ash House Hospital School, Sheffield, for their assistance.The expenses of the investigation were defrayed by a grant from the Medical Research Council.

scholarly journals Ward floors and other surfaces as reservoirs of hospital infection

1967 ◽  
Vol 65 (4) ◽  
pp. 515-536 ◽  
Author(s):  
G. A. J. Ayliffe ◽  
B. J. Collins ◽  
E. J. L. Lowbury ◽  
J. R. Babb ◽  
H. A. Lilly
Keyword(s):  
Bacterial Contamination ◽  
Hospital Infection ◽  
Staph Aureus ◽  
Air Movement ◽  
Large Numbers ◽  
Equilibrium Level ◽  
Rapid Accumulation ◽  
Floor Surfaces ◽  
Contaminated Area

Impression plates from initially clean horizontal surfaces and floor areas in surgical wards showed a rapid accumulation of bacteria, mainly micrococci, which reached a fluctuating equilibrium after about 24 h. A later increase in bacterial contamination (mainly with aerobic sporing bacilli) to a higher equilibrium level after about 14 days occurred on uncleaned areas. Walls, even if left unwashed, acquired very few bacteria, but many were deposited locally when the wall was touched by a subject whose skin carried large numbers of staphylococci; moist exposed plaster was also heavily contaminated.Regular use of a disinfectant (‘Sudol’ 1 in 100) in cleaning a ward floor did not reduce the equilibrium level of bacteria on the floor.The transfer of staphylococci from contaminated to clean areas on the soles of shoes was demonstrated; the use of tacky and disinfectant mats did not appreciably reduce the transfer of bacteria by this route.Staphylococci deposited on a wall by a disperser were shown to be transferred from the contaminated area of wall to the hands of another subject who did not previously carry the organism; this subject was shown to transfer the staphylo-coccus to a wall which he touched.Attempts to redisperse by air movementStaph. aureuswhich had been shed by a disperser or by a contaminated blanket on to the floor surfaces had little effect; neither blowing with a hair dryer nor brisk exercise appeared to lift any of the staphylococci from a vinyl surface, and only small numbers were lifted by these measures from a terrazzo surface.The hazards of infection from the inanimate environment are discussed.

Studies on Eimeria praecox Johnson, 1930, in the chicken

Parasitology ◽  
1967 ◽  
Vol 57 (2) ◽  
pp. 351-361 ◽  
Author(s):  
P. L. Long
Keyword(s):  
Small Intestine ◽  
Life Cycle ◽  
Small Dose ◽  
Technical Assistance ◽  
Host Immunity ◽  
Single Exposure ◽  
Three Generations ◽  
Large Numbers ◽  
High Degree ◽  
First Time

E. praeox has been isolated in Britain for the first time and is similar in regard to its oocyst size, prepatent time, life-cycle and the development of host immunity to the reports of Tyzzer et al. (1932). Oocysts had mean dimensions of 20·4 × 17·45 μm and the first oocysts were discharged 83½ h after infection.Oocyst production and life-cycle studies suggest that at least three generations of schizogony precede gametogony and that at least one further generation of schizogony is needed to explain the oocyst reproduction resulting from a small dose of oocysts. Young chickens 1½–3 weeks of age were not such suitable hosts as older chickens (6 weeks) and the reproduction of the parasite was seriously reduced when large numbers (e.g. 105, 106) were used to infect chickens. A high degree of resistance to reinfection occurred after a single exposure to infection.Sporozoite infections of the caeca or cloaca resulted in the infection of the usual small intestine site; there was no development at the site of inoculation and attempts to infect the embryo allantois did not succeed.I wish to thank Dr M. Elaine Rose for the surgery required for the caecal infections, for her interest throughout and for help with the manuscript; Dr R. F. Gordon for help with the manuscript and permission to publish and Mr B. J. Millard for skilled technical assistance.

Equipment and Method employed in breeding Aëdes aegypti, L., for the biological Assay of Insecticides

1945 ◽  
Vol 35 (3) ◽  
pp. 227-230 ◽  
Author(s):  
W. A. L. David ◽  
P. Bracey ◽  
A. Harvey
Keyword(s):  
Aedes Aegypti ◽  
Medical Research ◽  
Human Blood ◽  
Research Council ◽  
Medical Research Council ◽  
Biological Assay ◽  
Larval Food ◽  
Large Numbers

A method of rearing large numbers of Aëdes aegypti for the biological assay of insecticides is described. The larval food found to be most satisfactory was a breadcrumb infusion. Blood is necessary for oviposition (human blood is best), but the main batches of insects destined for spraying are fed on water, sugar and raisins.This work is being carried out under a grant from the Medical Research Council. The authors are grateful to Prof. P. A. Buxton and Dr. V. B. Wigglesworth for advice and encouragement.

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