bluuebunny/crossref_metadata_2025 huggingface dataset:
Droplet Infection. Some Theoretical Considerations
Authors: Greenwood Major
Published: May 2009

It is generally accepted that the infection of many diseases is conveyed by the discharge of droplets containing the biological materies morbi in the acts of coughing, speaking, etc. In some cases, for instance that of measles, it is believed that if a person harbouring the materies morbi has the opportunity of projecting it upon the upper respiratory tracts of non-immunes, a considerable proportion of the latter will develop the clinical disease. In other cases, for instance cerebro-spinal fever or acute poliomyelitis, it is believed that although, in consequence of the activity of the primary source of infection, many other persons will acquire and harbour the materies morbi only a small proportion of them will develop the disease.
The Epidemic Curve of Smallpox
Authors: Martin W. J.
Published: May 2009

When a disease assumes epidemic proportions, it is now generally recognised that certain conditions govern the rise and fall of the epidemic wave. Farr was probably the first person to attempt to describe these conditions in quantitative terms. His theory was “ the real law (i.e. of the epidemic) implies that the ratio of increase goes on rapidly decreasing until the ratio itself is decreasing.” In the Appendix to the second Annual Report of the Registrar-General he discusses the progress of the smallpox epidemic which had spread through England and Wales in 1837–9, causing the deaths of over 30,000 persons. “Five die weekly of smallpox in the metropolis when the disease is not epidemic… Why do the five deaths become 10, 15, 20, 31, 58, 88 weekly and then progressively fall through the same measured steps?” He suggests, “amidst the apparent irregularities of the epidemic of smallpox and its eruptions all over the kingdom, it was governed in its progress by certain general laws.” He found that the deaths from smallpox in the quarters of the year during the epidemic increased up to the third quarter very nearly at the ratio of 30 per cent. “The rate of increase is retarded at the end of the third period, and only rises 6 per cent. in the next, where it remains stationary, like a projectile at the summit of the curve which it is destined to describe. The decline of the epidemic was less rapid than its rise.” He showed that the fall of mortality took place at a uniformly accelerated rate and calculated a “regular series of numbers” (such that the second differences of the logarithms are constant) for the decline of the epidemic.
The Distribution and Sanitary Significance ofB. coli, B. lactis aerogenesand Intermediate Types of Coliform Bacilli in Water, Soil, Faeces, and Ice-Cream
Authors: Bardsley Doris A.
Published: May 2009

This section of the work deals with the routine bacteriological examination of 2144 samples of water, of which 1102 contained lactose-fermenting bacilli, 4333 strains being isolated. Twelve strains which liquefied gelatine and 24 which gave anomalous MR and VP reactions were excluded from the coliform group; the remaining 4297 cultures were classified on the basis of the MR, VP, indol, citrate and uric acid tests.
An Enquiry into the Coli anaerogenes Bacteria
Authors: Bamforth J.
Published: May 2009

In the routine laboratory examination of specimens of faeces and urine, from time to time certain Gram-negative bacilli belonging to many different groups are encountered, which morphologically show no appreciable differences from the Gram-negative bacilli of the coli-typhoid group, but which however ferment the usual carbohydrate media employed in differentiation with the formation of acid only. Some ferment lactose quickly, others more slowly, and many not at all, but as with the other media no gas is formed. These organisms might be considered as belonging to the so-called B. coli anaerogenes group— a somewhat loose term which might include many different strains, some perhaps related to the colon group, others belonging to and related to the group of dysentery bacilli, and others showing no relationship to either.
A Study of the Chick-Martin Test for Disinfectants
Authors: Garrod Lawrence P.
Published: May 2009

1. A study of the suspension of dried faeces used in the Chick-Martin test, and of the process of disinfection in this test has shown that:

(a) The suspension of faeces is unstable, and rapidly forms a compact deposit.

(b) Surviving bacteria in critical dilutions of the disinfectant are contained exclusively in this deposit.

(c) Uncontrolled factors affect the degree of subdivision of the particles of faeces.

(d) The degree of subdivision of these particles materially affects the activity of a disinfectant in their presence.

2. It is suggested that these facts among others may account for inconstant results which the test is said to give.

3. A suspension of yeast is proposed as a possible alternative form of organic matter in such a test.
Further Studies on the Survival Time of the Bovine Tubercle Bacillus in Soil, Soil and Dung, in Dung and on Grass, with Experiments on Feeding Guinea-Pigs and Calves on Grass Artificially Infected with Bovine Tubercle Bacilli
Authors: Maddock E. C. G.
Published: May 2009

Autopsies on all the guinea-pigs kept for as long as 20 months failed to reveal any trace of tuberculosis, although the grass grazed by the animals was proved by subcutaneous inoculation to bear virulent organisms, which might have been expected to reach the alimentary tract in considerable numbers, at least in the earlier experiments.

By repeated infection of a grazing area it has been possible to induce tuberculosis in guinea-pigs grazed in the open and in those fed indoors on cut grass. In the 1932 experiment a total of thirty guinea-pigs were allowed access to plots of grass which had been infected, one, four and eight days previously and all failed to become infected. The combined experiments (1932 and 1933) suggest that under some weather conditions, animals, although admitted to pasture within a very short time of its infection may escape infection with tuberculosis, but that repeated infection of pasture results in a high incidence of disease in animals grazing on it.
A new species of micro-organism (Proteus melanovogenes) causing black rot in eggs
Authors: Miles A. A. , Halnan E. T.
Published: May 2009

1. An organism is described as a specific cause of black rot in two consignments of hens' eggs imported into England.

2. It produces the rot experimentally when inoculated into fresh eggs, and penetrates apparently normal egg shells.

3. Four hens inoculated with the organisms laid eggs that failed to develop the specific rot. The number of hens used was small, and no definite conclusion about the mode of infection can be drawn from the result of this experiment.

4. The organism is found in English soils and manures.

5. Eleven of 100 English hen sera agglutinated the organism in dilutions of 1 in 80 to 1 in 320.

6. The organism is provisionally placed in theProteusgroup, and the nameProteus melanovogenesis assigned to it.
A serological study ofHaemophilus influenzae
Authors: Platt A. E.
Published: May 2009

1. Of eighty-six strains of Haem.influenzaeisolated from the naso-pharynx of normal persons, sixteen had the general characters of Pittman's “smooth” type.

2. These sixteen strains and one “smooth” strain isolated from a case of meningitis were submitted to various serological tests, including the separation and partial purification of a carbohydrate fraction from the meningeal strain and from four of the sixteen strains.

3. By precipitin tests carried out with these purified fractions, it was possible to identify three of the five “smooth” naso-pharyngeal strains and the meningeal strain, as belonging to Pittman's typee, and one of the “smooth” naso-pharyngeal strains to Pittman's type a.

4. Some indication of grouping, within this small sample of smooth strains, was obtained by various other methods, such as precipitin tests carried out with simple saline washings or agglutination reactions; but, apart from the four type strainsa,b,eandf, received from Miss Pittman, no strain could be satisfactorily typed by any of these methods. Only by using partially purified polysaccharide fractions was it possible to assign any of the “smooth” nasopharyngeal strains to their correct type.

5. The testing of these naso-pharyngeal strains against antisera prepared against typesa,b,eandfby direct agglutination, showed that either many of these strains contained some proportion of the smooth antigens, or that the antisera contained antibodies acting on other antigenic components, although, in relation to the type strains themselves, they appeared to be specific.

6. The examination of the eighty-six strains, as a whole, revealed the extreme antigenic heterogeneity that has been noted by many previous workers.
Studies in the declining birth-rate, the Midlands and London
Authors: Martin W. J.
Published: May 2009

The variation in fertility between different sections of the London area has been, and in spite of the decline, still is, considerable. In London as a whole the birth-rate has fallen by 56 per cent since 1870–2, while the potential rate shows a decline of only 6 per cent. The fertility of the boroughs is highly correlated with the index of their social status. A higher birth-rate is recorded in the areas with a large proportion of unskilled or semi-skilled labour, a lower birth-rate in the areas with a high proportion of the professional and more affluent members of society. Other indices of relative poverty and wealth and hygienic conditions give a similar answer. The decline in fertility during the past 20 years is not sensibly related to these indices but appears in its rate to have been broadly equivalent throughout the area.
Some aspects of open-air education
Authors: Simpson J. V. A.
Published: May 2009

It was Heraclitus who said of his predecessors that they had much knowledge but no sense, and this criticism often comes to mind when workers pause in retrospect and wonder that the application of the quite adequate knowledge of a generation ago was not applied in a practical and wise manner. Perhaps it may seem that a long time elapsed after compulsory education was adopted before it was realized that a vast number of children were physically quite unfitted to benefit from the learning presented to them; and it was a still longer time before it was hesitatingly acknowledged that the art of living, the teaching of an hygienic way of life, was the most important aspect of education. For without this the benefits of the whole system are of little lasting worth or real utility. Thus it is that open-air education, born late in time, is of such paramount importance; because although ordinarily and primarily conceived for restoring delicate children to health, the main great permanent value of this work is that it teaches in a practical and pleasant manner the greatest of all arts—the art of living.
Vaccination of guinea-pigs and human beings against leptospiral infections
Authors: Smith J.
Published: May 2009

1. Guinea-pig vaccination experiments have shown that these animals can be rendered completely immune from infection with virulent strains of L. icterohaemorrhagiae when they are treated with non-virulent living vaccines, or formalinized, heat-killed, phenolized, and dettolized suspensions of virulent cultures.

2. Vaccination with homologous strains of L. icterohaemorrliagiae produced better immunity than when heterologous strains such as L. hebdomadis or L. icterohaemorrhagiae Rachmat are employed.

3. Immune bodies are demonstrable in the serum of guinea-pigs vaccinated with L. icterohaemorrhagiae Weil, and a lytic titre of 1/6 appears to indicate that sufficient protective antibodies are present.

4. Following upon vaccination and inoculation with virulent cultures, carrier conditions have developed in animals treated with chemically killed vaccines of L. icterohaemorrhagiae Weil and with living non-virulent suspensions of the heterologous strain L. hebdomadis and L. icterohaemorrhagiae Rachmat.
A Modified tellurite medium for the detection and isolation of Corynebacterium diphtheriae in routine diagnostic work
Authors: Kerrin J. C. , Gaze H. W.
Published: May 2009

1. A further improvement in the modified McLeod's medium (Gaze, 1933) has resulted from the substitution of saccharose for glucose with the addition of Andrade's indicator.

2. Of the total positive swabs, the saccharose-containing medium detected about 22 per cent which were negative on Loeffler's medium, whereas it failed to detect only 0·36 per cent.

3. On this medium colonies typical of the gravis, intermediate and mitis types are formed and can be easily differentiated with the aid of a hand lens. It is also invaluable for the isolation of pure cultures.
On the occurrence of dysentery-like organisms in the urinary tract of man in Mauritius
Authors: Webb J. Lewis
Published: May 2009

1. Organisms biochemically resembling the metadysentery bacilli of Castellani (1927) or sensu largo B. coli anaerogenes of Lembke (1896) have been recovered locally from the urinary passages of man.

2. These organisms were found in cases of enteric-like fevers, pyelitis and cystitis.

3. Similar to Dudgeon's slow lactose-fermenting bacilli of the urinary tract, they have been shown to possess marked haemolytic action for red blood corpuscles.

4. Serologically, they appear to fall into at least two groups of bacilli.

5. They are believed to be pathogenic.
Studies on the influence of diet on resistance to infection II. The effect of various diets on the resistance of mice to bacterial infection
Authors: Watson Marion
Published: May 2009

The preceding paper recorded experiments on the influence of various “natural” and “synthetic” diets on the fertility of breeding does, and on the growth and survival of young mice. The present paper records the relative resistance of mice, bred and reared or fed for shorter periods on these diets, toBact. typhi-murium, or to its endotoxin.
Antigenic structure of influenza viruses; the preparation of elementary body suspensions and the nature of the complement-fixing antigen
Authors: Hoyle Leslie , Fairbrother R. W.
Published: May 2009

There is much evidence to indicate that viruses, in certain cases at least, have an antigenic structure of comparable complexity to that of the bacteria. Hughes (1933) found that the serum of animals immunized with the yellow-fever virus contained two independent antibodies—precipitins and protective antibodies; the precipitinogen was distinct from the virus. Craigie & Wishart (1936) in investigations of the vaccinia virus have shown that, in addition to the elementary bodies, virus suspensions contain two soluble precipitable substances, the “L” antigen which is labile at 56° C. and the “S” antigen which is stable at 95° C. These antigens were readily demonstrated by precipitation, agglutination and complement fixation. Their nature and origin have not, however, been precisely determined. Bedson (1936), working with the psittacosis virus, prepared a soluble antigen, which was independent of the elementary bodies. It was most satisfactorily demonstrated by complement fixation.
The Mechanism of Self-Disinfection of the Human Skin and its Appendages
Authors: Burtenshaw J. M. L.
Published: May 2009

1. Four β-haemolytic strains ofStreptococcus, suspended in normal saline, showed progressive increase in mortality, as thepHwas lowered from 7·5 to 5·0; belowpH 5·0 the mortality was greatly accentuated.

2. Ether and alcohol extracts of human skin and its appendages were powerfully, saline extracts more weakly and inconstantly, lethal to the haemolyticStreptococcusand to certain other organisms.

3. The long chain fatty acids and soaps are the chief, if not the only, bactericidal constituents of skin and its appendages.

4. Experiments are described illustra ting the streptococcocidal effect of various acids occurring in animal fats.

5. Cystein and blood inhibit the streptoeoccocidal activity of skin fats and certain fatty acids. Ultra-violet light may increase this activity, or abolish, the inhibition exercised by cystein.

6. The mechanism of the sterilizing power of fatty acids and soaps, the influence exerted by cystein, blood, and ultra-violet light on the sterilizing power, of skin fats and fatty acids, and the relationship of skin fatty acids to lysozyme are discussed.
Cross-Infection in scarlet-Fever bed isolation wards
Authors: Stalker W. Stewart , Whatley Elizabeth , Wright Joyce
Published: May 2009

1. The incidence of cross-infection with Str. pyogenes during a period of four months was compared in two blocks occupied by scarlet-fever patients. One block was nursed by the bed isolation method and the other by the ordinary method in current use for multiple-bed wards.
2. The rules for the bed isolation blook are given.
3. The incidence of cross-infection with Str. pyogenes among patients in the bed isolation block was 20·3%, that among patients in the ordinary block 22·6%.
4. We concluded that the bed isolation nursing technique practised was not effective in reducing cross-infection with Str. pyogenes among scarlet-fever patients.
5. A further test of bed isolation nursing was made for six months, using the extra precaution of vacuum-cleaning the floors. We found that crossinfection was still occurring, but the incidence could not be estimated since the Str. pyogenes strains isolated had to be destroyed at the outbreak of war. At this time the serological typing had not been completed.
6. The importance of dust-borne and droplet-borne infection in addition to that of contact infection is discussed. The type of investigation required to decide whether cross-infection in multiple-bed scarlet-fever wards can be eliminated by the methods at our present disposal is outlined.
The chemical and physical investigation of germicidal aerosols: II. The aerosol centrifuge
Authors: Finn S. R. , Powell E. O.
Published: May 2009

The principle of the aerosol centrifuge is described, and an elementary mathematicaltreatment is given.

The relations between the behaviour of the centrifuge and its dimensions, speed and airflow have been tested experimentally on three machines. It is shown that the mathe-matical formulae given are an adequate basis for design.

Various applications are mentioned.
Epidemiology of haemolytic streptococcal infection in relation to acute rheumatism: II. Epidemic rheumatism
Authors: Green C. A.
Published: May 2009

Although multiple cases of acute rheumatism have been observed to follow waves of streptococcal infection in institutions (see Green, p. 369) there is doubt as to whether acuter heumatism itself becomes epidemic under such circumstances or whether the element of infectivity lies in the preliminary throat infection as concluded by Sheldon (1931).
Immunization against typhoid and paratyphoid with alcohol-killed, alcohol-preserved and heat-killed, phenol-preserved, vaccine
Authors: Climie Hugh
Published: May 2009

1. A comparison of the agglutinogenic response and reactions, both local and general, between a series of sixty-two persons immunized with alcohol-killed, alcohol-preserved, T.A.B.C. vaccine, and forty-four persons immunized with a much older heat-killed, phenol preserved, T.A.B.C. vaccine is described.

2. It was found that there was comparatively little difference between the two series in regard to O agglutinin response.

3. Vi agglutinins were found in 14·4 % of the alcohol-vaccine cases, but none appeared in the heat-killed, phenolized vaccine cases.

4. There was no significant difference in the frequency of local reactions, but the general reactions were markedly fewer in the alcohol-vaccine cases.

5. The occurrence of Vi agglutinin response in six out of fifteen cases given heatkilled, phenol-preserved, T.A.B.C. or T.A.B. vaccines intravenously is recorded.
The Influence of social conditions upon diphtheria, measles, tuberculosis and whooping cough in early childhood in London
Authors: Wright G. Payling , Wright Helen Payling
Published: May 2009

Before the war diphtheria, measles, tuberculosis and whooping cough were the most important of the better-defined causes of death amongst young children in the London area. The large numbers of deaths registered from these four diseases in the age group 0–4 years in the Metropolitan Boroughs alone between 1931 and 1938, together with the deaths recorded under bronchitis and pneumonia, are set out in Table 1.
Comparative studies on Salmonella strains isolated in Palestine from camels and a human being
Authors: Olitzki L.
Published: May 2009

Salmonella strains isolated in Palestine from camels could not be differentiated from a human strain isolated in the same country. The Palestine strains differ from S. kentucky by lower fermenting activities, but are antigenically identical with it.
Further Studies on Foot Perspiration and Its Action on Footwear
Authors: Colin-Russ A.
Published: May 2009

In continuation of previous work involving accentuated effects of perspiration on chrome upper leather, the present paper records observations of such effects in more complicated conditions.

Thus, effects were studied at varying temperatures and pH of tans, buffered tans, buffered perspiration, buffered perspiration coupled with tans, buffering material itself and soap solutions.

Particular reference is made to the influence of basicity on the stability of the chrome complex against perspiration in such buffered chemical systems. Brown grain leathers are considered as well as box and willow calf.

A method is evolved for minimizing spueing risks or the formation of Glauber's salts in the vamps of worn footwear, by appropriate treatment of the skins before cutting up into shoe upper components.

Finally, some foot-bath experiments and the dark, cracky grain of worn insoles are discussed from the general point of view of perspiratory action on footwear.

The writer acknowledges with thanks the assistance of Messrs L. P. Huggett, B.Sc., A.I.C., and W. H. F. Jackman, B.Sc., A.I.C., in the routine analytical work. His best thanks are also due to the Director and Council of the Research Association for permission to publish.
An outbreak of water-borne typhoid investigated by bacteriophage typing and ‘selective’ sewage examination
Authors: Gell P. G. H. , Hobbs Betty C. , Allison V. D.
Published: May 2009

1. By means of phage typing of Bact. typhosum, the source of infection in a boy who drank water from a polluted stream was traced backwards via water, sewage effluent, crude sewage and faecal specimens to unsuspected typhoid carriers in a large institution.

2. A nurse in the institution contracted typhoid fever, caused by the same phage type (C) of Bact. typhosum as was found (a) in the stools of typhoid carriers in the wards in which she was on duty, (b) in the crude sewage and sewage effluent from the institution, (c) in the stream into which the sewage effluent discharged, and (d) in the stools of the boy who drank the stream water. The nurse's sister, who had had an attack of typhoid fever a few months earlier, was infected with a different type (E 1) of Bact. typhosum and was therefore not the source of her sister's infection.

3.The laboratory technique is described for the examination of (a) samples of water, sewage effluent and crude sewage, using different selective and enrichment media, (b) large numbers of faecal specimens for enteric organisms by a preliminary pooling of specimens in batches of six or seven, and further examination of the individual specimens comprising a positive batch, thus effecting a saving of time and economy of media.

We wish to thank the Medical Officers of Health, sanitary inspector and the medical and nursing staff of the institution for their enthusiastic co-operation in the investigation.
Some practical applications of immunological principles
Authors: Barr Mollie , Glenny A. T.
Published: May 2009

General immunological principles appear to be of wide if not univeral application, and can be applied equally to the hyperimmunization of horses for the production of therapeutic sera, or to human immunization against diphtheria and tetanus. A wider knowledge of the results obtained in animals, chiefly guinea-pigs, rabbits and horses, can help in a better understanding of all that is involved in the immunization of children against diphtheria.

The response of an animal to an antigenic stimulus depends almost entirely on its previous experience of that antigen. If it has had no previous experience, antibody is produced slowly and in small amounts. If it has had previous experience, a change occurs in its antibody-producing mechanism which enables it on further stimulation to produce anti-body more rapidly and in larger amounts. To produce this effect the early experience must be adequate and followed by a sufficient period of rest. It is shown that the normal antitoxic values of animals can give considerable information on their previous experience of antigen; that this information can be made use of in the hyperimmunization of horses; and that inadequate primary stimuli and failure to provide adequate rest may lead to the production of antitoxins of low value and poor quality.

Two things are necessary for defence against toxins: circulating antitoxin and a high reactivity of the antibody-producing mechanism (potential immunity). Methods of immunization should be chosen so as to provide both these essentials.
Studies on immunization by a species antigen: III. The presence of an anti-immunity factor in Pneumococcus
Authors: Day H. B.
Published: May 2009

The bodies of pneumococci contain a constituent of protein origin which interferes with immunization.

This constituent can not only counteract the immunizing action of the species antigen, but reduce the immunity response to the type-specific antigen.

In heat-killed pneumococci (ordinary bacterial vaccine) the coagulation of the protein renders the anti-immunity factor relatively insoluble and minimizes its action.

In solutions of pneumococci the anti-immunity factor is liberated and reduces the immunity response to the type-specific antigen.

The immunizing effect of a small dose of heat-killed pneumococci can be abolished if the cocci be dissolved before injection. But a larger dose of dissolved vaccine produces immunity, the effect of the antigen predominating.

The anti-immunity factor is heat resistant at acid pH, but is destroyed by alkaline heat. In these respects it resembles the immunizing antigens.
The inhibitory action of the monoethyl esters of S-n-alkylthiomalic acids and the monoethyl esters of alkane sulphonyl succinic acids on the growth of Mycobacterium tuberculosis
Authors: McNally P. A.
Published: May 2009

1. A new series of compounds has been found which markedly inhibits the growth of Mycobacterium tuberculosis and M. smegmatis.

2. These substances are strongly haemolytic against human red blood cells.

3. The effectiveness of the antibacterial and haemolytic actions depends upon the length of the alkyl chain.

4. The antibacterial and haemolytic actions are reduced by human serum.
Entamoeba histolytica in wild rats caught in London
Authors: Neal R. A.
Published: May 2009

1. A description is given of active forms and cysts of an amoeba found in wild London rats, and morphologically identical with E. histolytica.

2. When inoculated into the caeca of young rats, the amoebae invade the wall and produce lesions.

3. Acute infections produced in experimental rats respond to treatment with emetine hydrochloride.

4. The naturally infected rats were restricted to a localized focus, in which cases of human amoebiasis were discovered, thus providing circumstantial evidence of the human origin of the infection, and throwing light on the possible role of rats as reservoir hosts.
Seasonal changes in the normal bacterial flora of fresh-water fish
Authors: Bisset K. A.
Published: May 2009

1. Bacteriological examination of large samples of Perch and Powan from natural and artificial waters has shown that a considerable decline in the normal bacterial flora of the fish occurs during the summer months. Reinfection occurs when the temperature falls.

2. These variations are largely attributable to the effect of temperature upon the immunological responses of the fish.

3. The bacteria concerned appear to be water bacteria, which invade the muscles and body cavity of the fish, as well as the gill and gut-content.

4. The degree of infection is also influenced by the bacterial content of the water.
Some observations on the reaction between horse serum and a pool of rabbit antihorse serum: I. The relative inhibitory effect of excess antigen and excess antiserum
Authors: Naylor G. R. E.
Published: May 2009

1. The participation times of a series of mixtures of horse serum and a pool of rabbit antihorse serum have been determined. The results have been presented in a table and isochrones drawn. Four distinct α procedure optima were found, suggesting that there may be at least four different antigen-antibody reactions concerned when horse serum reacts with a rabbit antihorse serum.

2. The reaction between horse serum crystalbumin and the same pooled rabbit antihorse serum has been investigated, and recorded-similarly.

3. Inhibition of precipitation was found to be more marked in the region of antigen excess than in the region of antiserum excess. Evidence is presented in support of the view that the occurrence of multiple zones may obscure this observation.

4. The results are compatible with the view that the second stage of the precipitation reaction is specific.

5. The isochrones correspond with Boyd's R type.
Studies in the dynamics of disinfection: XII. The effect of variation in pH on the rate of disinfection at 51°C. of standard cultures of Bact. coli.
Authors: Jordan R. C. , Jacobs S. E.
Published: May 2009

1. Standard Bact. coli cultures have been heated at 51° C. in phosphate buffered media having pH values ranging from 2·8 to 8·8, and survivor curves obtained.

2. Except at pH 3·9, the first continuous decline in viable numbers was followed by the establishment of a small fluctuating residual population which was apparently permanent.

3. The colony counts showed a moderate excess of unduly high values of x2, the bulk of which were encountered when the mortality was between 95 and 99·999%.

4. Prolonged incubation of the plates led to increased colony counts, but the rise was confined to the active disinfection phase. It occurred chiefly in the 95–99·999% mortality range and was moderate in degree. The x2 values were little affected.

5. The log survivors-time graphs of the disinfection phase were convex in type but approached linearity in the faster reactions. The logarithmic death-rate became maximal at about 90 % mortality and thereafter remained constant, though under the more acid conditions a somewhat lower rate was maintained. At pH 7·0 and 6·4 the curves were exceptionally straight.

6. Standardization of all the curves revealed a continuous change in shape with pH but, nevertheless, they could be placed in three closely knit overlapping groups which were best revealed by the variation in maximum death-rate.

7. The 50–99·99% mortality times were obtained either from the calculated regressions of log survivors on time over the linear portions of the curves or, outside that range, from the freehand curves. Maximum survival at all mortality levels occurred at about pH 6·5–6·6, i.e. close to the neutral point of pure water at 51° C. On both sides of this point sensitivity increased regularly but was abnormally high at pH 7·0 and 6·4.

8. Within these zones of abnormally high sensitivity the assessment of the effect of a given change in pH varied in amount and direction according to the mortality level chosen.

9. The enhanced resistance of a culture regenerated from the survivors of a disinfection at 51° C. and pH 7.0, as previously reported, could possibly have been largely due to a small increase in acidity but not to a slight shift towards alkalinity.
A food-borne outbreak of streptococcal infection
Authors: Reynell P. C.
Published: May 2009

1. A food-borne outbreak of streptococcal infection in a cavalry regiment is described.

2. A controlled therapeutic experiment was carried out on the forty-nine patients admitted to hospital. Those given chemotherapy recovered more quickly than the controls, recovery being most rapid in the group given intramuscular penicillin.

3.Typical scarlatiniform eruptions were seen in ten cases. Streptococcal antitoxin appeared to prevent the occurrence of rashes, but had no significant effect on the duration of fever and toxaemia.

4. Upper respiratory complications supervened in ten cases. Evidence is presented which suggests that they were due to cross-infection.
An outbreak of gastro-enteritis due toSalmonella derby
Authors: Mushin Rose
Published: May 2009

1. An outbreak ofSalmonella derby, involving sixty-eight patients, is described.

2. The organism was isolated from clinical cases, from carriers and also from dust in the wards, from a mouse and from a hand towel used by nurses.

3. The value of tetrathionate broth with subsequent cultivation on ‘SS’ agar as an aid to isolation ofSalmonellabacilli was confirmed.

4. Cultural and biochemical characters ofSalm. derbywere recorded.

5. The antigenic structure of the isolated strains ofSalm. derbywas demonstrated, showing the presence of factorland the absence of a minor flagellar antigen.

6. A serological response toSalm. derbyinfection was shown in patients, their sera containing H antibodies of a titre 1/20 to 1/320, whereas O agglutinins were absent at the time the tests were made.

7. Pathogenicity tests were performed on mice indicating the possibility of infectionper osor by intraperitoneal injections. Mice were found to be potential faecal and urinary carriers.
The absorption of fat during the consumption of diets rich in whole-grain and white breads
Authors: Walker A. R. P.
Published: May 2009

1. The fat metabolism of three healthy European adult males has been followed for periods lasting from 7 to 22 consecutive weeks; a fourth subject was observed for a much shorter period. During this time the subjects consumed: A, their usual diet; B, a diet including 1 lb. of standard bread, made from 95 to 100% extraction flour; C, a diet including 1 lb. white bread, made from 70% extraction flour; and D, their usual diet. During the usual diet periods A and D, standard bread was also eaten. While each subject consumed the type and amount of fat he was accustomed to, his variations in intake, especially during the experimental diet periods B and C, were small. The intakes of the four subjects ranged from 55 to 115 g. daily.

2. The average absorption of fat during the usual diet periods was 94·0%; during the standard bread diet, it also averaged 94·0%; during the white bread diet, it averaged 94·9%.

3. It is concluded that with daily fat intakes of the order used in this investigation, a diet rich in whole-grain bread when compared with one rich in white bread does not lead to any appreciable diminution in the amount of fat absorbed.
Inactivation of haemagglutinin and infectivity of influenza and Newcastle disease viruses by heat and by formalin
Authors: Chu C. M.
Published: May 2009

Progressive heat inactivation of N.D.V. at 54–58° C. for 15 min. is accompanied by parallel destruction of its haemagglutinating activity. Progressive heat inactivation of Lee virus at 50–54° C. for 15 min. is accompanied by parallel loss of eluting power and ‘enzymic’ action on ‘Francis inhibitor’. Formalin in low concentrations rapidly inactivates both N.D.V. and Lee virus without appreciable impairment of their haemagglutinating activity or ‘enzymic’ function. Higher formalin concentrations acting over several days may, however, produce a slow deterioration of the haemagglutinin of both viruses. It is suggested that heat destroys the infectivity of N.D.V. and influenza virus primarily by abolishing their haemagglutinating ‘enzyme’. The possibility of the existence of independent virus components, all of which are essential for full infectivity of these viruses, is discussed.
Natural antibodies in the blood serum of fresh-water fish
Authors: Bisset K. A.
Published: May 2009

1. Fresh-water fish possess serum agglutinins specific for the bacteria which parasitize their peritoneal and opercular cavities, and also for the bacteria inhabiting the water in which they live.

2. The titre of these agglutinins is low in spring and rises during the summer months, in a manner which corresponds to the summer decrease in infection.

3. Similar agglutinins are found in frogs.

4. These observations provide additional evidence that water bacteria are capable of parasitizing aquatic animals.
Studies in the dynamics of disinfection: XIII. The nature of the probit-log survival-time relationship in disinfections of standard cultures of Bact. coli at 51°C. under various conditions of pH
Authors: Jordan R. C. , Jacobs S. E.
Published: May 2009

1. The nature of the probit-log survival-time relationship in the disinfection of standard cultures of Bact. coli at 51° C. at pH values ranging from 2·8 to 8·8 has been studied.

2. It is concluded that there is a very close approximation to a bilinear form in all cases, though there was evidence that a continuous curve concave upwards and to the left would provide a better fit.

3. Probit limits, corresponding to the range of percentage mortality within which, having regard to the experimental error involved, an observation might lie, have been worked out. The range covered by these probit limits decreases as the percentage mortality rises.

4. These limits have been used to decide whether a bilinear or a single straight line treatment should be applied to certain sets of data. It is suggested that they would often materially assist in deciding the range over which linearity may be assumed in any given case.
Studies in the dynamics of disinfection: XIV. The variation of the concentration exponents for hydrogen and hydroxyl ions with mortality level, using standard cultures of Bact. Coli at 51°C
Authors: Jordan R. C. , Jacobs S. E.
Published: May 2009

1. Data obtained by the disinfection at 51° C. of standard cultures of Bact. coli at pH values ranging from 2·8 to 8·8 have been used for the calculation of the concentration exponents of hydrogen and hydroxyl ions. The times taken to reach various degrees of mortality from 50 to 99·99 % have been taken as measures of the activities of the ions.

2. The formula Cn×t = constant proved satisfactory for describing the data for all the mortality levels and at all the pH values tested except pH 2·8, 6·25, 6·4 and 7·0. In these instances the cultures exhibited heightened sensitivity, though the results at all, except pH 2·8, could be included when the 99·.99 % mortality times were used. The exponents increased sharply at pH values below 3·9.

3. The values of the concentration exponents varied similarly under both acid and alkaline conditions, according to the mortality level chosen. The largest value was obtained from the 90 % mortality times, there being a decrease when both higher and lower levels were employed. The changes were greater under acid conditions, when the values ranged from 0·60 to 0·25, compared with 0·60–0·47 for the alkaline reactions.

4. The mean of the pH values for maximal survival at the various mortality levels, derived from the regressions of log mortality time on pH, was ·51, but this was close to a point of greater susceptibility. Experimentally, maximal survival occurred at pH 6·65, which is very near to the neutral point of water at 51° C.

5. It is concluded that within the pH range 6·25–7.0 the hydrogen and hydroxyl ions were relatively inactive, the effects observed being due to other factors possibly including the action of undissociated water molecules.

The authors acknowledge with thanks the receipt of a grant from Messrs I.C.I. (Pharmaceuticals) Ltd. towards the expenses of this investigation.
The conglutination phenomenon: IV. The importance of the choice of complement when examining antisera for the presence of complement-fixing or complement-absorbing antibodies
Authors: Coombs R. R. A. , Hole N. H.
Published: May 2009

1. Anti-mallein and anti-typhoid sera produced in various animal species, including man, have been examined for complement-absorbing antibodies using the complements of the pig, horse, cat, man, dog, and guinea-pig, which is possible if use is made of the conglutinating complement-absorption test as well as the haemolytic complement-fixation test.

2. Complement-fixing antibodies which are not demonstrable when some complements are used may be detected when other complements are used; for example, antibodies to mallein in human antisera were only detected when the sera were tested with horse and cat complements.

3. These early results are published at this stage because of the obvious possible application of these methods in laboratory serological diagnosis. Further work is in progress to elucidate the underlying reasons for these observations.

4. The implications of the results are discussed from the practical and theoretical aspects.
Wartime rationing and nutrition in pregnancy. First communication
Authors: Obermer E.
Published: May 2009

1. An analysis is made of 238 total calorie, protein, fat and carbohydrate intakes during wartime. These represent the 24 hr. mean of 48 hr. investigations carried out at six-weekly intervals throughout pregnancy on 55 healthy working-class women on self-selected diets. These investigations were carried out from April 1943 to the end of 1946. Throughout this period, ‘wartime’ rationing conditions prevailed.

2. The total calorie intake is analysed. 49·8% of the series in the ‘first half’ of pregnancy and 46·9 % in the ‘second half’ of pregnancy were found to be suboptimal according to recognized standards.

3. The protein intake is analysed in terms of(a)total intake, and(b)g./kg. body-weight. The latter analysis showed that 33 % of the figures in the ‘first half’ of pregnancy and 46 % of the figures in the ‘second half’ of pregnancy were sub-optimal.

4. The percentage of animal protein is contrasted with that of vegetable protein; a satisfactory animal protein percentage is found. The latter is derived partly from the extra pint of milk and partly from adequate quantities of meat, offal and fish. Over 40 % of the women ingested no cheese at all. The remainder consumed relatively small quantities.

5. The total fat intake is analysed. Over 50 % showed a fat ingestion of more than 100 g./day.

6. The total carbohydrate intake is analysed and the average ingestion found to be below 300 g. An analysis of the amounts of bread eaten per day showed a large proportion of intakes below ½ lb. (225 g.) per day—76 % in the ‘first half’ and 75 % in the ‘second half’ of pregnancy. The potato intake was relatively higher. The mean daily consumption was 191 g. with a maximum of 435 g. A list is also given of the amounts of the other common farinaceous foods consumed.

7. An analysis is made of the percentage of total calories accounted for by protein, fat and carbohydrates respectively. When the figures are compared with the accepted standards of 15 % protein, 35 % fat and 50% carbohydrates, the findings are(a)a slight preponderance of low protein intakes, (b) a preponderance of high fat intakes, and (c) a preponderance of low carbohydrate intakes.

8. The figures for all three constituents—protein, fat and carbohydrate—compare favourably with those given in prewar surveys of nutrition in pregnant working-class women.
Capsules and mucoid envelopes of bacteria
Authors: Klieneberger-Nobel Emmy
Published: May 2009

Methods have been described by which capsules and mucoid envelopes of bacteria can be fixed and stained positively and differentially, proving they are of different natures. The capsule is of definite shape and outline, the slime is amorphous. Some bacteria may have capsules, some may produce slime, and in others the capsulated organisms may be embedded in amorphous slime, as, for example, in the Fried-lander bacillus and in thePneumococcus,type III. These properties are probably more or less characteristic for certain organisms or groups of organisms. Of course, loss of capsules, and loss of slime production do occur.

All bacteria which have capsules seem to possess special antigens (cp. Kauffmann's A-antigen). This was particularly shown for members of thecoli-oerosrenes-Friedlander groups andStreptococcus para-faecalis(Skadhauge). Organisms with L-antigens possess generally no capsular or mucoid envelopes of the type described, with one exception, viz. strain Bi 316/42.

By means of the capsule- and slime-staining methods here described, a densely staining edge was demonstrated in the bacteria examined, which—it is suggested—may comprise the cell wall and its adjoining cytoplasmic layer. Organisms supposed to have no cell walls (Myxococci) do not show this appearance.

The so-called ‘swelling reaction’ is a reaction between antiserum and homologous bacteria, by which the capsule becomes easily demonstrable. It seems doubtful that actual swelling takes place.
The serological relationship between vaccinia and ectromelia viruses
Authors: Dickinson Lois
Published: May 2009

1. Elementary body suspensions of vaccinia and ectromelia were obtained from rabbit skin and chick embryo or mouse liver and chick embryo respectively and used to immunize rabbits.

2. Judged by the complement fixation and haemagglutination tests, the viruses from different hósts were very similar antigenically. Ectromelia and vaccinia appeared closely related, the heterologous virus titres being usually lower than the homologous.

3. Elementary body suspension agglutination tests did not reveal a similar relationship between the two viruses, but were not satisfactory on account of the low antibody content of the antiectromelia sera.

4. Highly active ectromelia antisera were not obtained and there was no evidence of multiplication of this virus in rabbits.

5. Only slight neutralizing activity was demonstrated in the antisera.

6. Elementary body suspensions of ectromelia virus prepared from mouse livers, as well as the crude liver extracts, were soon inactivated. Egg membrane preparations were relatively stable.
The problem of diabetes mellitus in school medical administration
Authors: Sainsbury H.
Published: May 2009

The recent inclusion of the diabetic child in the list of children for whom special provision is required to be made by Local Authorities confronts the School Medical Officer with the following questions:

(1) To what extent does the disease exist in a school population?

(2) Is it increasing, and if so, to what extent?

(3) What is its significance in terms of morbidity?

(4) What is its significance as a source of loss of child life?

(5) To what extent is the disease subject to control?
Plague in South Africa: a study of the epizootic cycle in gerbils (Tatera brantsi) in the northern Orange Free State
Authors: Davis D. H. S.
Published: May 2009

1. The course of an epizootic of plague in thirty-four colonies of gerbils (Tatera brantsi) was observed by counting, at 4-weekly intervals, the number of burrows which, when they had been closed on one day, were found open on the next. One gerbil could open an average of eight burrows in one night.

2. Regular censuses on the twenty-one colonies which survived until the last phase of the epizootic showed that the gerbil population fell from about 420 at the end of June 1940 to none at the end of January 1941. From May 1941 to August 1942, 3-monthly counts revealed some recolonization, but field officers reported that between 1942 and 1951 the gerbils sometimes died from plague, and the population never regained its former level.

3. During 1940, two to four colonies died out every 4 weeks. The time of year seemed not to influence the course of the epizootic.

4. Pasteurella pestis was detected in some gerbil colonies 4–6 months before they died out.

5. Plague-infected gerbil fleas were found which had been immured in blocked deserted burrows for periods of up to 120 days.

6. The passage of infection was traced from the reservoir in gerbils to other wild rodents (Otomys irroratus, Rattus (Mastomys) natalensis), to house rats (Rattus rattus) and to man.