bluuebunny/crossref_metadata_2025 huggingface dataset:
Action of the Colours of Benzidine on Mice Infected with Trypanosoma Dimorphon
Authors: Wenyon C. M.
Published: May 2009

The investigations which form the subject of this paper were undertaken at the Pasteur Institute, on the suggestion of M. Mesnil. It is a pleasure to acknowledge my great indebtedness to M. Mesnil for the help and advice he so willingly rendered me whilst I worked in his laboratory. M. Nicolle and he very kindly placed at my disposal their unique collection of colours, which had been supplied them by various firms (notably the Farbenfabriken of Elberfeld). By their suggestions, without which this work would not have been accomplished, they saved me much time and labour. MM. Nicolle and Mesnil had been studying the influence of a large number of colours on various trypanosomes, chiefly Trypanosoma Brucei and to a less extent T. Evansi, T. equinum, and T. Gambiense. Their work was undertaken after the publication of Ehrlich and Shiga's paper on the action of Trypanroth, one of the benzidine colours, on Trypanosoma equinum. M. Mesnil suggested that I should investigate the action of these colours on T. dimorphon which differs in many ways from the above trypanosomes.
On the Larval and Pupal Stages of Anopheles Maculipennis, Meigen
Authors: Imms A. D.
Published: May 2009

The great importance of an exact knowledge of the etiology of malaria has given a remarkable impetus to the study of mosquitoes. It has resulted in the growth, during the last few years, of a very extensive literature relating to these insects, and especially to those of the genusAnopheles, which serve as the alternative and definitive hosts of human malarial parasites. Comparatively few writings, however, deal with their internal anatomy.
The Relative Frequency of Various Types of Streptococci in Scarlatina
Authors: Cumpston H.
Published: May 2009

It has long been well established that during the height of scarlet fever streptococci flourish and become greatly predominant in the pharyngeal and buccal mucus. To quote only a few of the many recorded observations.
An Investigation into the Acid-fast Bacteria found in Human Faeces with Special Reference to their Presence in Cases of Tuberculosis
Authors: Alexander D. Moore
Published: May 2009

Up to the year 1906 tubercle bacilli were considered to occur in the faeces only in pulmonary or abdominal tuberculosis, due to ingestion of the infected sputum or to ulceration of the intestinal tract.
The Toxigenic Features of Strains of the Diphtheria Bacillus isolated from Horses and from a Mule
Authors: Petrie G. F.
Published: May 2009

In December, 1920, Capt. F.C. Minett, R.A.V.C., of the Royal Army Veterinary School, Aldershot, published an account of diphtheria bacilli isolated by him from eleven horses and one mule. He states that during the last year of the War and for some months after the Armistice the laboratory at the Army Veterinary School received for examination numerous specimens of pus derived chiefly from suspected cases of ulcerative lymphangitis; a condition in horses in which swelling of the lower parts of a limb or limbs is accompanied by abscess formation followed by ulceration. From this material he collected and investigated a number of diphtheroid strains including the bacillus of Preisz-Nocard and in the course of his inquiry discovered twelve strains of the diphtheria bacillus.
The Spread of Bacterial Infection. The Potential Infectivity of a Surviving Mouse-Population, and their Resistance to Subsequent Epidemics of the Same Disease
Authors: Topley W. W. C.
Published: May 2009

In a previous communication (1921) experiments have been described showing the effect produced by continuously adding normal mice to a cage, the population of which is infected with bacilli of the group which includes B. gaertner and B. suipestifer. It was seen that under these circumstances the spread of infection progresses in a series of epidemic waves, and that the survival-time of any batch of mice varies according to the period at which they are introduced to the cage. It was further shown that, if such regular and continuous addition of susceptible animals be persisted in over long periods of time, all the micewill eventually succumb, while, if the addition of new individuals be discontinued, the epidemic will eventually subside, leaving a proportion of survivors who may remain in apparently good health over a considerable period.
Air Carriage of Pathogenic and other Organisms
Authors: Buxton J. B. , Allen H. R.
Published: May 2009

From the foregoing experiments, it may be assumed:

(1) That given favourable conditions, such as a direct current of air through a building, organisms derived from animals, their fodder or environment, may be disseminated over distances up to 150 feet from the building.

(2) That B. welchii is frequently present in the dust and dirt of buildings in which horses and small laboratory animals (guinea-pigs and rabbits) are housed, and

(3) That under suitable conditions, spore-bearing anaerobes such as B.welchii, may be carried with infected dust from such buildings, for a distance of at least 90 feet, and probably considerably further.
The Diet in the Different Grades of Society in Denmark
Authors: Heiberg Povl
Published: May 2009

In the persent communication a general survey of the diet in the different levels of society in Denmark will be given for the first time.

The material dealt with consists of about 1000 household accounts which the state statistical department has published in the course of time.
The Influence of Avitaminosis on the Course of Trypanosome Infection
Authors: Fine J.
Published: May 2009

Recent research has shown that the term “anti-infective” applied to vitamin A is misleading and inaccurate. Harris (1933) has discussed the evidence which shows that vitamin A cannot be regarded as a general antiinfective agent: the actual relation of the vitamin to infection has been well defined by Cramer, who states (1930) that “an adequate supply of vitamin A is a powerful prophylactic against infections entering by mucous membranes, but there is no evidence that it can prevent or cure those infections which enter by the blood stream or by subcutaneous tissues.”
The Haemophilic Bacteria of the Upper Respiratory Tract, the Appearance of Virulent forms in Relation to Upper Respiratory Infections
Authors: Hoyle L.
Published: May 2009

In previous studies of the bacterial flora of the upper respiratory tract and its variations during attacks of acute coryza (Hoyle, 1932), it was found that there was in many cases a striking relationship between the appearance of certain organisms with definite pathogenic properties towards the lower animals, in the upper respiratory tract, and the occurrence of acute infections. This relationship was especially marked in the case of the influenza bacillus, and it was suggested that this organism played a prominent part in the aetiology of upper respiratory infections. The significance of the influenza bacillus in acute coryza has been noted by various workers (Noble, Fisher and Brainard, 1928; Burky and Smillie, 1929; Webster and Clow, 1932; Kneeland and Dawes, 1932), but on the other hand various observers have found the incidence of influenza bacilli in the respiratory tract to be the same in normal health and in acute coryza, and Fleming (1929) and Fleming and Maclean (1930) have devised a technique by means of which they claim to have isolated influenza bacilli in 100 per cent, of normal throats. One possible explanation of these conflicting results may be found in the absence of any very exact criterion of what constitutes a typical influenza bacillus.
The Absorption of Hydrocyanic Acid Vapour Through the Skin: with Notes on Other Matters Relating to Acute Cyanide Poisoning
Authors: Fairley A. , Linton E. C. , Wild F. E.
Published: May 2009

The original scope of this investigation was the study of the passage of hydrocyanic acid vapour through the skin. We have partly repeated and confirmed the results of Walton and Witherspoon (1926). In view of the extensive use of hydrocyanic acid vapour in the destruction of vermin in ships the subject is of considerable practical interest. In the course of our work certain other matters were considered and these are referred to in the text.
The Examination of Cotton, Coir and Esparto-Grass Dust for Histamine
Authors: Macdonald A. D. , Maitland H. B.
Published: May 2009

As a result of some preliminary investigations upon the aetiology of an asthmatic type of disability among workers in carding-rooms of cotton mills, Maitland, Heap and Macdonald (1932) showed that it was possible to extract from some samples of cotton dust a substance which gave the biological reactions of histamine. The dust was that to which affected workers would be exposed. The amount of histamine recovered varied from 0·02 mg. to less than 0·004 mg. per g. of dust. Different bulk samples of dust contained unequal amounts, and the amount also varied in different fractions of one sample graded according to the size of dust particles. It was thought that the finer fractions contained the larger amounts of histamine and that some bulk samples were, relatively at any rate, histamine free.
The endotoxin of the meningococcus
Authors: Petrie G. F.
Published: May 2009

1. The view is advanced that the endotoxin of the meningococcus is one of a group of thermostable intracellular bacterial poisons, and that it is not a specific antigenic toxin. 2. The inability of the “endotoxin” to function as an antigen does not lessen its importance as a pathogenic factor in cerebrospinal fever, since the lesions that are associated with the presence of the meningococcus in the tissues are apparently attributable to the pyogenic action of the intracellular poison.
Co-agglutination betweenB. typhosusandB. paratyphosusB
Authors: Wyllie J.
Published: May 2009

Co-agglutination between the somatic agglutinins ofB. typhosusandB. paratyphosusB occurs more frequently than between the flagellar agglutinins in the sera of typhoid and paratyphoid B fever cases. These co-agglutinins may develop early or late in the course of the disease.

It is suggested that the agglutinin absorption test is capable of distinguishing whether or not true co-agglutinins have been developed to the flagellar and somatic antigens ofB. typhosusorB. paratyphosusB.
Contributions to the mathematical theory of epidemics IV. Analysis of experimental epidemics of the virus disease mouse ectromelia
Authors: Kermack W. O. , McKendrick A. G.
Published: May 2009

1. The experimental data obtained by Greenwood et al. (1936) relating to epidemics of the virus disease ectromelia in mice have been examined in the light of mathematical theory. Attention has been directed in particular to the life tables calculated from the observed data, which give the chance of survival and death after various periods of cage life.

2. The life table relating to ectromelia 1 during the steady state phase from 1. iii. 32 to 31. viii. 32 shows very close agreement over the range 0–550 days with that predicted by the theoretical equation which involves only four arbitrary constants. A slight discrepancy over the first few days is evidently due to the fact that representation of the death-rate and the recovery rate by constant coefficients does not accommodate an incubation period. The values of the constants obtained from the data give a measure of the essential characteristics of the epidemic.

3. General agreement, though not so complete, is also found when the theory is applied to ectromelia 2 during the priod 1. xi. 31–30. iv. 32. During this phase however, although conditions were otherwise apparently uniform, a steady state had not actually been attained. On the other hand the equations do not apply so satisfactorily to the obviously inhomogeneous period 1. v. 32–20. x. 32.

4. In the present analysis the assumption of constant rates gives a satisfactory account of the progress of an infection in a susceptible community. This result suggests that for many purposes the assumption of constant rates may be adequate.

5. The short period fluctuations observed in the ectromelia epidemic were probably random in character and have no relationship to periodic fluctuations such, for example, as those detected by Brownlee in the case of measles.
Note on the variation in the vitamin B1 activity of raw wheat germ.
Authors: Baker A. Z. , Wright M. D.
Published: May 2009

Arising out of the routine selection of wheat germs for the production of a composite high-value and reasonably uniform mixture, it has been found that the variation in the vitamin B activity of unselected wheat germ is greater than has been generally suspected.
The serological types of haemolytic streptococci in epidemic scarlatina
Authors: Green C. A.
Published: May 2009

1. Bight serological types of haemolytic streptococci were recognized in acute scarlatina during the 1933 epidemic in Edinburgh.

2. Five of these types were identical with Griffith's types 1, 2, 3, 4 and 5, while the remainder have been named, provisionally, B, C and D.

3. Type 5 was predominant during the two months preceding the epidemic and throughout the early development of the outbreak.

4. The epidemic was maintained by successive increases in the proportion of cases due to the remaining type, particularly type 3.

5. The age-group incidence in the epidemic year was identical with that of non-epidemic years.

6. 36·8 per cent of patients on discharge were found to have haemolytic streptococci in the throat but in only 5·4 per cent was a large number of organisms isolated.

7. Haemolytic streptococci isolated from discharged convalescents were in the majority of cases of the same type as the admission strain.
A comparison of the mesencephalon and hippocampus as sites of election for Negri bodies in rabies
Authors: Horgan E. S. , McKinnon R. M.
Published: May 2009

A comparative examination of the hippocampus and mid-brain in a series of 37 brains from suspected rabid animals has shown the marked superiority of the hippocampus as the site of election for Negri bodies.
Growth ofStreptococcus pyogenesin milk stored at atmospheric temperatures
Authors: Pullinger E. J. , Kemp Audrey E.
Published: May 2009

1.Streptococcus pyogenesmultiplies readily in sterilized milk stored at 22 and 18° C., and more slowly at 15° C. In fresh raw milk this organism begins to multiply slowly only after 48–72 hours of storage at 18–22° C. In laboratory pasteurized milk the result is similar, but both commercially pasteurized milk and raw graded milk bottled for distribution sour too rapidly for multiplication to take place after artificial contamination. These facts suggest that widespread epidemics are rarely due to extensive multiplication ofS. pyogenesin milk during commercial or household storage.

2. The initial degree of contamination of milk withS. pyogeneshas no influence upon this organism's ability to multiply during storage.

3. The failure ofS. pyogenesto multiply during storage is due to (a) its natural reluctance to grow at atmospheric temperatures, (b) the bacteriostatic action of the milk, and (c) the readiness with which saprophytic bacteria multiply at atmospheric temperatures.

4. It is contended that infected cows play a major part in the spread of milk-borneS. pyogenesepidemics, and relevant literature is quoted to support this view. It is urged that routine investigation of apparent milk-borne epidemics should include the immediate bacteriological examination of an individual sample of milk from every cow concerned in the supply under suspicion.
The Significance of the Variation in Shape of Time-Survivor Curves
Authors: Withell E. R.
Published: May 2009

The mean time-survivor curves of bacteria immersed in two phenolic disinfectants show the same variation of type as the individual curves, that is, (a) an exponential rate, (b) a lag phase followed by an exponential rate. The significance of all these curves and of others is discussed in the next part of the paper.
An anaerogenic strain of Proteus
Authors: Edwards J. L.
Published: May 2009

A Proteus-like organism is described, which produced acid but no gas in carbohydrate media.

I wish to thank Dr W. D. Carruthers,. Medical Officer of Health of Staffordshire, for permission to publish this paper.
The occurrence of toxigenic anaerobes, especially Clostridium botulinum, in some English soils
Authors: Haines R. B.
Published: May 2009

1. Examination of samples of soil from 106 localities by enrichment culture technique gave 37% toxic samples, the percentage containing Clostridium botulinum ranging from a certain 5% to a possible 14%.

2. Cl. botulinum type A was shown to be present in four of the five positive samples, type B in one. Characteristics of a pure culture of type A are given.

3. Incidental data on the occurrence of some other toxigenic anaerobes are given.
Epidemiology of haemolytic streptococcal infection in relation to acute rheumatism: III. Comparative incidence of various infections and acute rheumatism in certain training centres
Authors: Green C. A.
Published: May 2009

The distribution of various infectious diseases in certain training centres is discussed inrelation to the streptococcal aetiology of acute rheumatism, and the relative importance of age and environment are noted.

It gives me real pleasure to acknowledge the interest and support of Vice-Admiral Sir Percival Nicholls, K.C.B., and Vice-Admiral Sir S. F. Dudley, K.C.B., F.R.S., throughout these investigations which were facilitated by the willing co-operation of numerous officers and personnel of the R.N. Medical Service. To Surg. Capt. F. Hitch and the staff of the R.N. Medical School I am greatly indebted, particularly for the efficient technical assistance rendered by Petty-Officer L. Waller. The work was carried out during tenure of the Erederick Pearson-Sir Halley Stewart Naval Research Fellowship of the Empire Rheu-matism Council.
Staphylococcus aureusin the milk of nursing mothers and the alimentary canal of their infants: A report to the Medical Research Council
Authors: Duncan J. T. , Walker Jacqueline
Published: May 2009

Investigations at two hospitals, P and S, showedStaphylococcus aureusto be commonly present in the milk of healthy nursing mothers and the throat and intestine of their babies. In hospital P, the proportion affected in a group of eighty-two mothers and their babies was over 90%. The condition may not be uncommon in maternity hospitals, but no information of its occurrence is available from private obstetrical practice. The cocci concerned seemed to be of low virulence, for babies swallowing relatively massive doses in their mothers' milk suffered no perceptible ill effect. On the other hand, the coccus was found in the pus of the only case of breast abscess encountered, and in some minor external pustular lesions. It was present in the milk of all the cases of flushed breast examined, but its causal connexion with this condition awaits proof.

The staphylococci, in the majority of cases, seemed to occur first in the baby's throat, possibly from a focus of infection in the babies' ward, and to be transmitted from baby to baby and from baby to mother, with a return infection, in larger amount, through the mother's milk. The mother's nose and throat must be included amongst other, but less frequent, sources of the infection.

The predominating type ofStaph. aureusgave a relatively strong coagulase reaction which was caused only by actively growing cocci, but it would seem that the reaction caused by this agency is less trustworthy as an index of virulence of the coccus than one in which free coagulase also operates.
Reclamation of used agar
Authors: Brodie James , Stiven David
Published: May 2009

Owing to the entry of Japan into the war it is essential that agar should be used as economically as possible. Since October 1941, we have, in this laboratory, reclaimed used agar by the following simple method, which is a modification of the procedure described by Huang, Shen & Tang (1941).
Fluorosis and the parathyroid glands
Authors: Spira Leo
Published: May 2009

There is a close similarity between the dental changes produced experimentally in the rat by parathyroidectomy and mottled teeth as seen in man and known to be caused by protracted ingestion of toxic amounts of fluorine. In view of the fact that both parathyroidectomy and fluorine produce dystrophies in tissues regulated by the parathyroid glands it is concluded that, in man, mottled teeth, certain dermatoses, mottled nails and alopecia may be due to a disturbance of these glands brought about by the ingestion of toxic amounts of fluorine in drinking water.
Mottled Nails. An Early Sign of Fluorosis
Authors: Spira Leo
Published: May 2009

Signs and symptoms attributed to a disturbed function of the parathyroid glands as a result of the protracted action of small quantities of fluorine have been described elsewhere (Spira, 1942c). It was shown that the lesions on the teeth known as ‘mottled enamel’ were frequently accompanied by lesions on the skin and its appendages, the nails and hair. The object of the present communication is to give some details of the changes produced in the finger- and toe-nails in chronic fluorine poisoning (fluorosis).
Studies on infant mortality: Part I. Influence of social conditions in county boroughs of england and Wales
Authors: Woolf Barnet , Waterhouse John
Published: May 2009

1. The Introduction (pp. 67–73) describes the course of infant mortality in England and Wales over the past century, and critically reviews arguments advanced to prove that variations in the infant mortality rate (i.m.) are caused by genetic differences with respect to viability.

2. The i.m. in county boroughs shows a 2-yearly cycle of variability, affecting places with high mortalities.

3. We have devised and tested various social indices and have selected five which gave the highest joint covariance with infant mortality in county boroughs during the 11 years 1928–38. These indices are:

H, percentage of families living more than 1 person per room.

U, percentage of men unemployed.

P, percentage of occupied males in the Registrar-General's Social Classes IV and V.

F, percentage of women employed on manufacturing processes.

L, latitude.

4. We have computed multiple regression equations involving i.m. and the five indices for each of the 11 years, and two summarizing equations. The regressions plus sampling variance account for about 80% of the total variance in infant mortality. The regression is linear.

5. Latitude does not affect infant mortality in Class I. For this and other reasons we regard the latitude effect as expressing miscellaneous poverty indices omitted from our equations.

6. The regression equations enable us to divide the population into various strata with characteristic average infant mortality rates. These include:

‘Better off’ (all poverty indices = 0) i.m.=23·1

Overcrowded poor i.m. = 108

Unemployed overcrowded poor i.m. = 153

Babies whose mothers work in industry suffer an additional mortality risk of at least 35 per 1000, and possibly more. The figure 23·1 is the i.m. rate that would prevail if our five poverty symptoms could be eliminated.

7. In county boroughs two-thirds of infant deaths would be avoided by the abolition of conditions defined by our indices. Of the preventable deaths, one-third are associated with overcrowding, one-quarter with low-paid occupations, one-fifth with unemployment, and one-eighth with industrial employment of women. In England and Wales, over 250,000 deaths in 11 years, about 63% of the total, can be attributed to adverse social conditions.

We have to thank the Rockefeller Foundation for a personal grant to one of us (J. W.) out of an allocation for research work in Prof. Lancelot Hogben's Department, and the Halley Stewart Trust for a grant for mechanical computing equipment. Our thanks are also due to the various members of the Zoology Department in the University of Birmingham who assisted in computing at various times, and especially to Prof. Hogben for his unfailing interest, advice and support.
Changes in the nuclear structure of bacteria, particularly during spore formation
Authors: Klieneberger-Nobel Emmy
Published: May 2009

Changes of nuclear structure in bacteria have been studied by means of the hydrochloric acid-Giemsa method which produces brilliantly stained specimens and can be carried out with almost the same ease as some of the ordinary routine staining techniques.

The nuclear changes in the four spore-bearing organisms studied are outlined in Text-fig. III, to which the following numbers refer. The dumbbell bodies which are dispersed in the cells of the young growth (1) become alined in the long axis of the cell (2) where they eventually fuse into an axial nuclear cylinder (3, 4). These cells divide up into fusion cells of approximately the same length (5). The development of the ‘chromosome’ stage (1) into the fusion cell (5) is the first step in the process of sporulation. During its further development the fusion cell or spore mother cell divides twice (6, 7), with the result that it is segregated into four structures which often assume dumbbell shape. Therefore the chromatin cylinder of the individual spore mother cell seems to be equivalent to four nuclear elements one of which functions as the spore ‘chromosome’ (‘nucleus’?), whereas the remaining three disintegrate (8, 9). The ripe spore (9) representing, as it does, the smallest cell unit contains one nuclear structure only.

Therefore the two main features in spore formation of bacteria appear to be (1) a fusion of the dumbbell bodies into an axial chromatin rod (‘autogamy’?), (2) a reduction partition which is reminiscent of, though not corresponding to, the more complicated phenomenon of meiosis in the higher organisms. The sporulation, as outlined in this paper, gives new proof of the important part played by the chromatinic dumbbell bodies (‘chromosomes’) in the developmental cycle of spore-bearing organisms. The fusion cell with its axial chromatin cylinder has for the first time been proved to have a progressive functional significance as a stage in a nuclear cycle. The particular mode of fusion followed by reduction partition suggests that the chromatinic dumbbell bodies may be concerned with the transmission of the hereditary characters in bacteria.
Bacterial lysis and antiseptics
Authors: Pulvertaft R. J. V. , Lumb G. D.
Published: May 2009

When a number of organisms are exposed in early rapidly multiplying broth cultures to minimally effective bacteriostatic concentrations of a number of antiseptics, almost complete lysis may be demonstrated.

When older cultures are exposed to low concentrations, or young cultures to strong concentrations, lysis does not occur in many cases.

The lytic effect of penicillin is apparently identical with that of the antiseptics tested. The phenomenon appears to depend on the nature of the effect of the antiseptic on metabolic enzymes, autolytic enzymes, or both.
Cross-infection in hospital due to Salmonella derby
Authors: Rubbo Sydney D.
Published: May 2009

1. An outbreak of gastro-enteritis in hospital due to Salmonella derby is described.

2. The probable pathways of infection are indicated diagrammatically (Text-fig. 2).

3. Attention is drawn to the importance of dust as an environmental source of infection in gastroenteritis in a closed community.

4. Methods of control including the detection of carriers, the avoidance of contact with anything that goes into an infant's mouth and the protection of exposed food from dust contamination are stressed.
Haemolytic disease of newborn foals due to iso-immunization of pregnancy
Authors: Coombs R. R. A. , Crowhurst R. C. , Day F. T. , Heard D. H. , Hinde I. T. , Hoogstraten J. , Parry H. B.
Published: May 2009

1. Six cases of haemolytic disease in newborn foals apparently due to iso-immunization of pregnancy are described from their clinical, serological, haematological and pathological aspects. The findings agree closely with those seen in the same disease in newborn mules.

2. The disease may be diagnosed serologically by demonstrating the in vivo iso-sensitization of the foal's red cells by means of the direct antiglobulin-sensitization test. It is quite possible that after further investigation a modification of Diamond's albumin tube test may also be of value. Immune anti-red cell iso-antibodies of more than one specificity may be demonstrated in the dams' sera.

3. Despite the acute haemolytic process, very few reticulocytes and no erythroblasts are seen in the peripheral blood.

4. The morbid histology of the tissues of foals dying with the disease exhibits various points of interest which are discussed.

5. The clinical aspect is not described in this paper in any detail. However, a programme is suggested which would enable a successful exsanguino-transfusion of compatible blood to be carried out at very short notice. At present this seems to be the logical and most practical method of specific treatment.
A study of rheumatic fever and streptococcal infection in different social groups in Melbourne
Authors: Holmes Margaret C. , Rubbo Sydney D.
Published: May 2009

1. Hospital records of 1469 cases of rheumatic fever (including chorea) up to the age of 14 years were used to study the social distribution of the disease in Melbourne. On this evidence the incidence of rheumatic fever was three times greater in low than in high rental districts.

2. The results of throat-swab surveys and Dick tests on schoolchildren living in different districts showed that children in the poor districts contracted streptococcal infections more frequently than those in well-to-do districts.

3. One factor associated with the carrier rate ofStreptococcus pyogenesin the various social groups was the incidence of tonsillectomy. In the better class districts where the tonsillectomy rate was high (60%) theStr. pyogenescarrier rate was 12.5%, whereas the rates in poor areas were 35 and 25.3% respectively.

4. Differences in social incidence of rheumatic fever might therefore be explained by differences in social incidence of streptococcal infection, which, in turn, might be influenced by the incidence of tonsillectomy.

We wish to thank the many persons who so willingly assisted in the collection of data for this study, particularly Dr H. L. Stokes and Dr M. M. Wilson, and Dr R. E. O. Williams for advice on presentation. This work was supported by a grant to one of us (Dr M. C. Holmes) from the Commonwealth Research Fund from the University of Melbourne.
Enumeration ofStreptococcus faecalis, with particular reference to polluted waters
Authors: Allen L. A. , Pierce Margaret A. F. , Smith Hazel M.
Published: May 2009

Factors affecting the growth ofStreptococcus faecalison glucose-yeast extract-sodium azide agar have been studied. Both the high temperature of incubation used (45° C.) and the presence of azide reduced the proportion of cells able to form colonies, the inhibitory action being much more marked with cultures which had become attenuated, either through age or through prolonged immersion in water, than with comparatively young and vigorous cultures. This inhibitory action was found to be largely overcome if the inoculum was subjected to a preliminary period of ‘resuscitation’, by incubating it with double-strength glucose broth before adding the azide-agar portion of the medium and allowing the mixture to set.

Neutral red was so inhibitory to some strains ofStr. faecalisthat it could not be included in the medium. Phosphate, as the potassium salt at a concentration of 0.7%, if autoclaved with the remaining constituents of the medium, exerted a depressing effect on the counts. Added separately it showed no inhibitory action.

The spinning-bottle technique (Allenet al.1952) was adapted forStr. faecalis. When used for samples containing a mixed flora the method, described in the Appendix, permitted the growth only ofStr. faecalis.

This paper is published by permission of the Department of Scientific and Industrial Research.
Improved methods for determining the most probable number ofBacterium coliand ofStreptococcus faecalis
Authors: Childs Eileen , Allen L. A.
Published: May 2009

Three methods have been investigated for determining Most Probable Numbers, using lactose-bile salts broth forBacterium coliand glucose-yeast extract-azide broth forStreptococcus faecalis. In the ‘direct’ method inoculated tubes of medium are incubated directly in a water-bath, at 44° C. forBact. colior at 45° C. forStr. faecalis. In the ‘subculture’ method primary incubation at 37° C. is followed by subculture of positive tubes to tubes of fresh media which are incubated at the higher temperature. In the ‘resuscitation’ method each medium is divided into 2 parts. The inoculum is mixed, in McCartney bottles or tubes, with the first part of the medium, containing the sugar and the peptone, and the mixture is held at 37° C. for 1–2 hr. to resuscitate organisms weakened by age or by long immersion in water. The second part of the medium, containing the bile salts or the azide, is then added and the bottles or tubes are incubated at 44 or 45° C. With samples of polluted waters the ‘subculture’ method gives significantly higher counts than the ‘direct’ method forStr. faecalisbut not forBact. coli.The ‘resuscitation’ method gives significantly higher results than the ‘subculture’ method for both organisms, it requires less time for completion, and is specific for the organism concerned.

These results were obtained with media containing 0.003% brom-cresol purple as indicator; neutral red was found to be inhibitory.

This paper is published by permission of the Department of Scientific and Industrial Research.
A group of viruses isolated from naturally infected mosquitoes collected in the Murray Valley area of Victoria and New South Wales
Authors: French E. L. , Reeves W. C.
Published: May 2009

By the inoculation of suspensions of mosquitoes on the chorio-allantoic membrane of chick embryos, seven pock-producing viruses have been isolated. The mosquitoes were collected in a small area of the Murray Valley situated in the north-western corner of Victoria and southern New South Wales. Six of the viruses were isolated from pools ofC. fatigansand one from a pool ofC. annulirostris. Five of the viruses were found to be members of the bird pox group and related to fowl-pox virus. Two of the viruses differed in the type of pock they produced on the chorio-allantoic membrane and appeared to be serologically unrelated to the other five.

The interest and criticism of Sir Macfarlane Burnet, F.R.S., throughout the conduct of this work is gratefully acknowledged.
Tetanus antitoxin titration by haemagglutination
Authors: Fulthorpe A. J.
Published: May 2009

The behaviour of sheep cells sensitized with tetanus toxins and toxoids in the presence of antitoxin has been investigated.

Sensitized sheep cells were agglutinated in the presence of tetanus antitoxin. The agglutinin titres of such direct agglutinin systems were roughly proportional to the antitoxin content of the sera with some marked exceptions. The discrepancies were associated with the presence of non-specific agglutinins (antibodies other than specific antitoxin) and with the immunization history of the horses providing the sera.

When sensitized cells were used as indicators of the presence of free antitoxin in toxin or toxoid-antitoxin mixtures, the correlation within vivotests was quite good at the L+ level of test, but not so reliable at the 0·01 L+ level of test.

Sensitized cells preserved with formalin were found to be more reliable and the results with such materials were more reproducible than those obtained with freshly prepared sensitized cells.

Cells sensitized with different concentrations of antigen gave different titres by direct agglutination with simple dilution of antitoxin; this difference was very much less in haemagglutination inhibition tests.

The LAdose (the volume of toxin or toxoid which when mixed with one unit of antitoxin gave a + + ± end-point) varied according to the sensitivity of the suspension used and the purity of the components of the reacting mixtures.

Prozones (zones of agglutination inhibition in the region of antibody excess) were found to be associated with the immunization history of the horses from which the sera were obtained. In general the more thorough the immunization the longer the prozones found. The length of prozones was proportionately increased with decrease in the concentration of sensitizing antigen. Possible reasons for the behaviour of certain antitoxins in these tests have been discussed.

I am indebted to Prof. M. Raynaud of the Pasteur Institute, Garches, for the supply of tetanus toxoids of high purity.

I am very grateful to Mr Charles Newman for considerable technical assistance.
An intra-oral inoculation technique for the production of experimental pneumonia in mice
Authors: Epstein S. S. , Breach G. D.
Published: May 2009

Techniques for the production of experimental pneumonia are briefly reviewed. A new method of intra-oral inoculation in the anaesthetized mouse is described and its advantages with particular reference to the danger of aerial contamination and facility of technique discussed. An application of this method to virulence studies is indicated and other possible applications suggested.

The author would like to express gratitude to Dr I. Friedmann for having made this work possible and for his advice and help at all stages. He would also like to thank the late Sir E. L. Kennaway, Dr F. Fulton and Dr D. A. Osborn for helpful suggestions, Prof. E. T. C. Spooner for the kind loan of the Bourdillon apparatus, Dr S. T. Cowan for an N.C.T.C. strain of Klebsiella, Mr P. Payne for statistical advice and Mr D. Connolly for the photomicrograph.
The fimbrial antigens ofShigella flexneri
Authors: Gillies R. R. , Duguid J. P.
Published: May 2009

1. ‘Pure fimbrial antisera’ were prepared forSh. flexneristrains of O-serotypes 1a, 2b, 3 and 4aand 5, by injecting rabbits with a living fimbriate-phase culture and absorbing the crude immune serum with a non-fimbriate-phase culture of the same strain to remove antibodies for the non-fimbrial (somatic) antigens. These sera gave at high titre a rapid, loosely floccular agglutination of all fimbriate-phaseFlexnericultures, caused adhesion of their fimbriae visible by electron-microscopy and inhibited their haemagglutinating activity. ‘Non-fimbrial antisera’, prepared by injection of non-fimbriate-phase cultures, were devoid of these activities; they gave somatic-type agglutination with fimbriate bacilli at lower titres than with homologous non-fimbriate bacilli, the fimbriae tending to mask the O-antigens and confer relative O-inagglutinability.

2. Heating at 90°C. detached the fimbriae from the bacilli, so that these lost their haemagglutinating activity, fimbrial serum agglutinability and fimbrial agglutinin-binding power. When heated for 21/2 hr. at 100°C., the detached fimbriae retained agglutinin-binding power, but lost their immunogenicity.

3. Cross-agglutination and absorption tests showed that the antigenic composition of the fimbriae was identical in allflexneristrains, irrespective of O-serotype. Theflexneripure fimbrial antisera agglutinated at low titre sixty out of sixty-six fimbriateBact. colistrains. Absorption tests with aflexneriand threecolipure fimbrial antisera showed that the fimbriae ofSh. flexnericontained a major‘flexneri-specific antigen’, found in only onecolistrain, one or more minor ‘flexneri-coliantigens’ shared by a fewcolistrains. Thecolifimbriae also contained a major,‘colitype-specific antigen’ shared in groups of several related strains. Theflexnerisera did not react with fimbriate strains ofBact. cloacae, SalmonellaandProteus.

4. Fimbrial agglutinins forSh. flexneriwere found in eighty of eighty-one normal human sera at titres from 30 to 1920, and in some pre-immunization rabbit sera at titres of 30 to 60.
Epidemiology of staphylococcal infections
Authors: Roodyn Leonard
Published: May 2009

During the period 1951–58, a study has been carried out of a series of seventeen families in which more than one member developed a staphylococcal lesion.

In eleven of these families, phage typing revealed that spread of infection from person to person had occurred. Once introduced into a household, the staphylococcus demonstrated great persistence; a particular strain could cause recurrent lesions in different members for as long as 6 years. The interval between the first and subsequent infection in another member of the same family was most irregular, but was usually 2–11 months.

The patient with recurrent furunculosis appeared to be mainly responsible for dissemination of strains.

In six out of the seventeen families, although multiple infections were encountered in the household, these were not due to case-to-case spread because more than one phage type of staphylococcus was isolated.

In one family investigated, there had been a dissemination of a hospital-acquired staphylococcus to another member of the household.

No infections were encountered in which the ‘epidemic strain’ 80/81 was responsible.

I wish to express my gratitude to Dr R. E. O. Williams of the Staphylococcal Reference Laboratory, Colindale, for his assistance in this work.
Further observations on an insecticide-bait-box method for the control of sylvatic plague vectors; effect of prolonged field exposure to DDT powder
Authors: Kartman Leo
Published: May 2009

A field experiment was conducted from July 1958 to February 1959 in the San Francisco Bay region to test the effect on flea populations of prolonged exposure of the native meadow vole, Microtus californicus, to 5% DDT powder in insecticide-bait-boxes. Previous studies had shown that two important vectors of sylvatic plague, Malaraeus telchinum and Hystrichopsylla linsdalei, could be controlled both on their hosts and in the host nests by this method. However, the question of possible resistance was postulated since the control of H. linsdalei on its host was inferior to control of other flea species.

Bait-boxes with DDT powder were maintained in the field for 6 months. Records of flea populations on Microtus during this period showed equally good control of all flea species. Observations on vole nests at termination of the study revealed deposits of DDT and good control of all flea species in them. During the period of study, the evidence suggested that none of the flea species involved exhibited DDT resistance.

The major portion of the field routine was done by Messrs A. R. Kinney and R. L. Martin. Flea identifications were made by Mr H. E. Stark. Analyses of nests and rodents for DDT were performed by Mr C. Cueto, Technical Development Laboratories, CDC, Savannah, Georgia.
The evaluation of ventilation
Authors: Lidwell O. M.
Published: May 2009

The problem of describing quantitatively the effective ventilation in a room when the air within the room is imperfectly mixed is discussed. It is suggested that the protection afforded by the ventilation to any given position against airborne contamination liberated at any other position can be best expressed in terms of the integrated exposure at the first point following liberation of a tracer substance at the second. This quantity is called thetransfer indexand its reciprocal theequivalent ventilationapproaches numerically to the rate of supply of ventilating air as the mixing of air within the room approaches completeness. Nitrous oxide is a convenient tracer gas for making such measurements.

A method is also described whereby estimates of thetransfer indexcan be made employing only such apparatus as is easily available in a reasonably well-equipped laboratory. This method employs acetone vapour as a tracer substance. The concentration of this vapour in the air is measured by the pH change produced in a dilute solution of hydroxylamine hydrochloride as it flows down a cotton wick exposed to the atmosphere.
Observations on a poliovirus variant
Authors: Austin F. J. , Miles J. A. R.
Published: May 2009

1. Some of the biological and physical properties of one member (FES) of an inter-related group of viruses were examined and compared with the Saukett strain of poliovirus Type 3.

2. The accumulated data of particle size, immunological relationship, and host tissue and cell tropism indicates that this is a naturally occurring non-neurotropic strain of poliovirus Type 3. It shows a slight immunological difference from Saukett, and also differs from it in temperature stability.

3. The significance of four different isolations of this agent in a brief period is discussed.
An environmental survey of bakehouses and abattoirs for salmonellae
Authors: Harvey R. W. S. , Phillips W. Powell
Published: May 2009

1. Moore's gauze swabs have, in our hands, been shown to be a reliable instrument for the survey of salmonella infection in the environment of two food premises.

2. A large bakery was demonstrated to be regularly contaminated with salmonellae. Thirty-one floor gully swabs out of 111 (27·9%) were positive for salmonellae. Little spread of infection to the general public was experienced.

3. Staff infection with salmonellae was shown to occur in this bakery. Fifteen positive specimens of staff sewage out of 93 were obtained (16·1%). There was little evidence of prolonged contamination of the sewers with salmonellae. Staff infections were probably, therefore, of short duration. The staff probably became infected from contaminated goods in the bakehouse. Rat contamination of sewers was excluded by water trapping.

4. It is not thought that regular examination of staff excreta would be a profitable means of discovering carriers or of preventing contamination of the products. The frequency with which such examinations would have to be performed to discover short-term excreters would be administratively impossible.

5. Of 274 swabs from gullies in abattoirs, 111 were positive for salmonellac (40·5%). Twenty-one different serotypes were isolated. Seventeen of these serotypes are known to occur in animal feedingstuffs.

6. Parallel examination of abattoir swabs and excreta from human infections forS. typhimurium, coupled with phage-typing of the strains, provided information of the geographically local nature of much sporadic illness due to this serotype. Of a total of 30 typable strains, 23 belonged to phage-types found in the abattoirs, or on local farms. Sporadic incidents were represented by 25 of these cultures, 18 of which corresponded in phage-type to those found in the abattoirs or in local farm animals. The phage-types ofS. typhimuriumisolated from the slaughter houses not infrequently corresponded in timing with the strains isolated from human infections.
The epidemiology of infectious hepatitis in Israel
Authors: Davies A. Michael , Suchowolski A.
Published: May 2009

1. The incidence of infectious hepatitis calculated from official notifications fluctuated between 5·7 and 11·4 per 10,000 during the years 1949–57, while reports of the Workers' Sick Fund indicated a rate three to four times greater. The highest rates were between the ages 1 and 9, two-thirds of the cases being under 10. Mortality was very low.

2. Highest attack rates were seen under conditions of crowding, i.e. in agricultural schools, communal settlements and new immigrant towns. This fact, together with the winter peak of incidence, suggests a contact-respiratory form of spread.

3. Immigrants, regardless of country, showed particular susceptibility during their first year or two in Israel. In the long run there was no difference in attack rate between immigrants from Western and from Middle Eastern countries, in spite of the known endemicity of the disease in the Middle East. In communities such as those from Yemen and North Africa, with large families and with, on the whole, a lower economic status, the mean age at onset was significantly younger. Among the non-Jewish population, the incidence was lower than expected due partly to under-reporting and partly, perhaps, to a mild form of the disease in the very young.