bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on Experimental Tuberculosis in Mice The Susceptibility of Mice to Inoculation with Tubercle Bacilli
Authors: Browning C. H. , Gulbransen R.
Published: May 2009

(1) Mice can be readily infected with many strains of B. tuberculosis, both of human and bovine type, by intraperitoneal inoculation with a dose of 0·75 milligramme of moist culture. But, with a fairly virulent culture of bovine type, doses of 0·005 milligramme produced infections of almost the same duration as the larger doses.

(2) The investigation of seven cultures of human and six of bovine type showed that in general the animals infected with the bovine strains survived. for a shorter time than those infected with the human strains. Also, several human cultures failed to produce infection, whereas no failure occurred with the bovine cultures. But no constant difference was found between the duration of infections with the two types of bacilli. Thus rapidly fatal infections were produced by certain cultures of both types.

(3) The period of survival of infected animals depends partly on the particular culture used for inoculation, and partly on the individual resistance of the animal and, in the case of nearly full-grown mice, is independent of their weight at the time of inoculation.

(4) The effect of repeated passage of tuberculous material from mouse to mouse without interposing cultivation of the bacilli on artificial media was investigated with eight strains, the series of passages numbering from three to eight. Increase of virulence was repeatedly observed, but such increase was never maintained in subsequent passages. The evidence indicates that the individual host plays an important part in modifying the virulence of the organisms for other members of the same species.

(5) As regards maintenance of virulence, comparatively constant results were obtained with different subcultures of the same strain. But repeated tests over a period exceeding five years have given indications that the virulence of a strain may become altered spontaneously from time to time.
Food-Poisoning Due to Bacillus Suipestifer (Sub-Group II).
Authors: Scott W. M.
Published: May 2009

Four outbreaks of food-poisoning are described in which over 100 cases in all of gastro-enteritis occurred, one being fatal. In each outbreak the infecting bacteria were indistinguishable culturally and in serological behaviour from the “G” strain of B. suipestifer.

The reasons are given for following Andrewes and Neave and classifying these as B. suipestifer. (sub-group II).
Contributions to the Experimental Study of Epidemiology. Further Observations on the Effect of Vaccination on Herd Mortality
Authors: Greenwood M. , Topley W. W. C. , Wilson J.
Published: May 2009

In the last memoir of this series (Greenwood, Topley and Wilson, 1931) we discussed at some length the modifications of the course of herd sickness effected by immunisation of entrants to the herds. Briefly, these were our conclusions: efficient artificial immunisation (the criteria of efficiency being the usual standardising methods of a laboratory) confers a considerable temporary advantage upon mice entering an infected herd. The risk of death during the period of herd life when the rate of mortality is especially high is greatly reduced, so that when one has the case of a herd or group temporarily exposed to special risks, the value of the expedient is very great. But no method of artificial immunisation we have tried will render the immunised animals impervious to the risks which their membership of the herd entails.
The Bactericidins of Normal Serum: Their Characters, Occurrence in Various Animals and the Susceptibility of Different Bacteria to their Action
Authors: Mackie T. J. , Finkelstein M. H.
Published: May 2009

Since the early work of Nuttall (1888), Buchner (1889), and others first disclosed the bactericidal property of normal serum, a considerable amount of attention has been devoted to this important biological phenomenon. The literature (which has been reviewed recently by Knorr, 1929) lacks, however, a comprehensive and co-ordinated study of the subject, and in fact presents a good many confusing data in regard to the nature of the active principles concerned and their immunological significance.
The Classification of the Colon-Aerogenes Group of Bacteria in Relation to their Habitat and its Application to the Sanitary Examination of Water Supplies in the Tropics and in Temperate Climates. A Comparative Study of 2500 Cultures
Authors: Burke-Gaffney H. J. O'D.
Published: May 2009

(1) The ”lactose+ indol+” index as employed in temperate climate is usually an adequate criterion of water purity.

(2) Where a positive test does not appear to be substantiated by the sanitary findings, a further differentiation of the organisms isolated becomes necessary. The methyl-red and citrate tests have been found to supply that differentiation in a satisfactory manner.

(3) In the Tropics, false positive “lactose-indol” tests are commonly encountered, owing to the presence in large numbers in soil and water of organisms derived from sources other than recently excreted faeces.

(4) In the Tropics, the lactose-indol test should always be confirmed by the methyl-red, citrate and saccharose tests or such other reactions or groups of reactions as may be found by a local survey to be applicable.

My very grateful thanks are due to Dr P. A. Clearkin, Deputy Director of Laboratory Service, Tanganyika Territory, for his ready advice and constant encouragement; and also to Mr W. Whitley, Analytical Chemist, who performed a chemical analysis of the water samples, and very kindly gave me the benefit of his opinion on them. In addition I have to thank Dr R. R. Scott, Medical Officer of Health, and the Staff of the Health Office, Dar-es-Salaam, who have rendered every facility in the choice and collection of samples. It is a pleasure to be able to record once more my indebtedness to Prof. Bigger, of Trinity College, Dublin, whose fund of valuable suggestions and kindly criticism has been ever at my disposal.
Physiological Response to Breathing Hot Air
Authors: Killick Esther M.
Published: May 2009

The following investigation was made, at the request of the Mine Rescue Research Committee of the Safety in Mines Research Board, as to the upper limit of temperature at which air can be breathed without distress under various conditions. During the use of self-contained breathing apparatus in rescue work, the air circulating in the apparatus becomes heated and saturated with moisture, and the question arises of the limiting temperature of inspired air that a man can tolerate while resting and while doing work, and which is therefore permissible for an apparatus.
The Influence of Radiant Heat and Air Movement on the Cooling of the Kata-Thermometer
Authors: Bedford T. , Warner C. G.
Published: May 2009

The factor of the kata-thermometer as deduced from the relation

F = 0·27θ × cooling time in seconds

is not constant, but increases as θ decreases. The relation between F and θ is shown, and it is recommended that the factor should always be corrected to the value corresponding to a temperature of 60° F.

The rate of heat-loss calculated from the factor determined by the still air method is not the true value, but under-estimates it. If the true value is required it can be obtained with reasonable accuracy by increasing the still air value of the factor by 20 per cent, in the case of the body-temperature kata, and 31 per cent, in the case of the high-temperature instrument. For ordinary use however, it is recommended that the still air factor should continue to be used.

Observations were made in still air with standard kata-thermometers and also with silvered instruments. From these observations, and from determinations of the emissivity of the bulbs, the heat loss by radiation was estimated. The remainder after deducting the radiation loss from the total heat loss gave the loss by convection. Estimations of the convection loss from the silvered and plain katas corresponded closely. An equation is given for the convection loss in still air.

The whirling arm method was used for investigating the effects of air velocities up to 1 m. per sec., corrections being made for swirl. The equation deduced from these observations on the standard body-temperature katas was practically identical with the equation of Hill, Vernon and Hargood-Ash. An equation of similar form was found for the silvered body-temperature kata-thermometers, and equations are also given for the high-temperature instruments. When the true rate of heat-loss is used it is found that one equation can be made to fit the observations with both high-temperature and body-temperature instruments, whether the bulb surfaces are of glass or silver.

It is shown that in places where the temperature of the surrounding surfaces differs from the air temperature, a much more reliable estimate of the air velocity can be obtained if a silvered kata is used instead of the plain glass instrument.

A method is given for measuring the emission of radiation from the surroundings by means of ordinary and silvered kata-thermometers, and it is shown that estimates so made correspond, to within 1 per cent., with the values obtained by direct thermopile measurements.
The Fatty Infiltration of the Liver of Mice resulting from the Ingestion of Medical Liquid Paraffin, etc
Authors: Twort C. C. , Twort J. M.
Published: May 2009

The fatty infiltration of the liver which follows the ingestion of medicinal liquid paraffin and many other varieties of mineral oils is more prevalent among females than among males, and is more prevalent among pigmented eye animals than among albino eye animals. When access to the oil lasts for about 30 weeks some 40 per cent, of pigmented eye females and 20 per cent. of the albino eye males may show the condition.

It is the intermediate products, lubricating oils, obtained by distillation of a crude mineral oil which contain the bulk of the constituents which lead to fatty infiltration of the liver, while it is the so-called “spirits” and the residues left in the still which tend to lead to excessive hyaline degeneration of the organs in general. There is evidence to show that fatty infiltration of the liver and hyaline degeneration of the organs are mutually antagonistic, but there is little evidence to show that either condition is directly related to the cancerous process.
Microbic Dissociation: Detection of the “R” Variant by means of a Specific Drop-Agglutination
Authors: Pampana Emilio J.
Published: May 2009

The characters by which the “R” variant of a given bacterial type is distinguished from the “S” variant are to-day widely known. Most of them are morphological and in most bacterial types it is not difficult to say whether a single colony is smooth or rough; but every bacteriologist is familiar with those borderline colonies, which are apparently smooth, but which later prove to be serologically rough. It sometimes happens that by special stimulation the reversion from an “R” culture into the “S” form succeeds, but that, notwithstanding the smooth appearance of the isolated colonies, the organisms persist in showing some characters which belong to the “R” variant, such as instability in saline (Bruce White, 1926).
The significance of volatility and water solubility in disinfection processes
Authors: Twort C. C. , White L. J. , Baker A. H.
Published: May 2009

1. Solubility of a germicide in the medium (water or air) in which it is operating appears often to be the most important physical characteristic governing degree of activity on bacteria (partition law).

2. Evidence of the importance of solubility has only been derived from a study of the action of phenols and glycols, a high bactericidal activity never being registered unless solubility was low.

3. Other types of germicide were exceptional in that high solubility coincided with high bactericidal activity: iodine and maleic anhydride in the air; mercuric chloride and many organic acids in the test-tube.

4. Mixtures of germicide and bacteria as used in the test-tube were sprayed into the air, the bactericidal effect being usually increased or decreased according as to whether it was originally low or high in the test-tube.

5. The vapour pressures of most of the germicides used were deduced from the Clausius and Clapeyron formula, the boiling-points being determined by the bubbling method.

6. When the amount of a phenol used in the air is approximately proportional to the vapour pressure, the bactericidal effects of the different samples are more nearly parallel when the degree of saturation of the air is low than when it is high.

7. No phenol with a vapour pressure lower than 0·0021- mg. Hg, and tested at full saturation, sterilized the air during the first minute of the experiment, while all samples with, at least, 10 times this vapour pressure did so when at 12·5 % saturation.

8. Among the phenols tested, especially those having low vapour pressures, the concentration (w/w) in air is very much less than the concentration in water in the respective experimental conditions, where but few survivors is the criterion of efficacy. Owing to a number of different factors, the rapid decline in the initial concentration is more likely to be met with under air than under test-tube conditions.
The evaluation of culture media for the isolation ofl salmonellaell from faeces
Authors: Smith H. Williams
Published: May 2009

The sensitivity of different culture media for isolating salmonellae from the faeces of man, dog, horse, cow, sheep, pig, chicken, duck and turkey has been investigated. Suitable dilutions of tissue fluids of animals that had died from salmonella infection, and in which the numbers of viable salmonellae could be accurately estimated, had previously been added to the faecal specimens. Tissue fluids containing Salmonella dublin, typhi-murium, thompson, cholerae-suis, gallinarum and pullorum were used.

Selenite and tetrathionate media were greatly superior to liquid desoxycholatecitrate medium, liquid Wilson and Blair medium, cacotheline broth and brilliant green peptone water. By the use of either selenite or tetrathionate media it was usually possible to recover salmonellae from faecal specimens to which less than ten salmonellae had been added. They could nearly always be recovered from specimens containing 100 salmonellae.

Salmonellae were more easily recovered from the faeces of some species of animals than others. For selenite, the order of ease of recovery was horse, followed by sheep, human, cow, chicken, pig, turkey, dog and duck faeces, and for tetrathionate, horse, sheep, human, dog, pig, cow, turkey, chicken and duck faeces.

Selenite medium was preferable to tetrathionate for examining cow and chicken faeces but the reverse was true in the case of dog faeces; slight differences only were noted in the other species. Taken as a whole, selenite was slightly superior to tetrathionate, butbest results were obtained by the use of both media.

Some types of salmonellae were easier to recover from faeces than others.Of six salmonella types, Salm. thompson was easiest to recover followed by Salm. typhi-murium, dublin, gallinarum, pullorum and cholerae-suis, in that order.

Erroneous results were obtained when laboratory cultures were used instead of infected tissue fluids.

It was necessary to add several thousand salmonellae to faeces before they could be recovered by direct culture on desoxycholate-citrate-agar or Wilson and Blair solid medium.

Salm. cholerae-suis and Salm. abortus-ovis were exceptional in that direct plating was superior to the use of enrichment media.

With lightly infected specimens an incubation period of 24–30 hr. was optimum for selenite and tetrathionate media. A longer period was detrimental with tetrathionate but not with selenite medium.

The combination of selenite and solid Wilson and Blair medium was sometimes too inhibitory to permit the growth of salmonellae.

There was little advantage in preparing selenite medium with mannitol instead of lactose.
Structure of the influenza virus. The relation between biological activity and chemical structure of virus fractions
Authors: Hoyle L.
Published: May 2009

Influenza virus elementary bodies can be disintegrated by treatment with ether with the liberation of two types of smaller particle, soluble antigen and red cell agglutinin.

Soluble antigen derived from the elementary body is identical in serological and chemical behaviour with soluble antigen recovered from infected tissues. Its chemical properties are those of a ribonucleoprotein.

The agglutinin is an enzyme, with a protein part carrying the enzymic activity and a combining group with affinity for red cells. The agglutinin does not react in complement-fixation tests by the short fixation technique, but by the use of prolonged fixation or by indirect complement fixation it can be shown to contain a strain specific antigen and also a non-specific antigen. The specific antigen is identical with the specific complement-fixing antigen demonstrable in the intact elementary body, and has combining affinity for red blood cells. The non-specific antigen is probably similar to the protein part of the soluble antigen. No evidence has been found that the agglutinin contains either carbohydrate or nucleic acid.

From the ether used to disintegrate the elementary body a serologically active lipid can be recovered which has properties suggesting that it is derived from the host cell.

The author is greatly indebted to Dr L. Dmochowski for assistance in experiments involving high-speed centrifugation, to Sir Macfarlane Burnet and Dr G. L. Ada for supplies of receptor-destroying enzyme, to Dr E. S. Duthie for crystalline trypsin and chymotrypsin, and to Dr R. R. Porter for a sample of crystalline ribonuclease.
Vesicular stomatitis and foot-and-mouth disease: analysis of mixed infection in cattle
Authors: Brooksby J. B.
Published: May 2009

1. It has been found possible to detect traces of the virus of foot-and-mouth disease in mixtures of this virus and that of vesicular stomatitis by cross-immunity tests in cattle. A quantity of the virus of foot-and-mouth disease as small as 1·3 I.D. 50 was revealed by the inoculation of such mixtures into cattle immune to vesicular stomatitis.

2. It is suggested that such a method would be useful in the analysis of possible mixed infections in field outbreaks.

3. The usefulness of complement-fixation tests to confirm the resolution of mixtures has been demonstrated.

The author wishes to thank the Director of this Institute, Dr I. A. Galloway,
for his advice and encouragement. The technical assistance of Messrs E. Scoates
and P. M. Mitchell is also gratefully acknowledged.
Nasal mucus and influenza viruses. II. A new test for the presumptive diagnosis of influenza infection
Authors: De St Groth S. Fazekas
Published: May 2009

Changes in the inhibitory properties of human nasal mucus were found to be positively correlated with objective signs of influenza virus infection during the 1950 epidemic. In approximately 80% of the cases the inhibitor index was significantly increased during the acute stage of the disease, and reverted to normal during convalescence.

Various respiratory diseases other than epidemic influenza did not cause similar changes.

Examination of the inhibitory pattern of nasal mucus is proposed as a presumptive test for influenza virus infection, and its merits are discussed under the headings of reproducibility, specificity and sensitivity.
The Vi antigen ofSalmonella paratyphi A
Authors: Felix A.
Published: May 2009

1.Salmonella paratyphi Apossesses a specific Vi antigen essentially similar to that of the Vi antigen ofSalm. typhi.

2. O-insensitive strains ofSalm. paratyphi Acontain more Vi antigen, and are more virulent for mice, than O-sensitive strains.

3. The most suitable strains for the preparation of paratyphoid-Avaccine are those that develop both the Vi and the O antigens in maximum quantities. The methods of selecting the vaccine strain ofSalm. paratyphi Aand routinely examining the cultures are essentially the same as those applied to the virulent Vi+O form ofSalm. typhi.

4. Pure A Vi antiserum is destined to assume importance in the identification ofSalm. paratyphi Astrains.

5. Kauffmann's erroneous conclusion thatSalm. paratyphi Adoes not develop Vi antigen is critically reviewed.
The serological classification of Bacteriaceae
Authors: Felix A.
Published: May 2009

1. Four different Bacteriaceae possessing the same Vi antigen showed, after exposure to heat, striking differences in the physico-chemical behaviour of the Vi antigen. The most noticeable differences observed were those in the changes in Vi-agglutinability and O-inagglutinability of the bacteria; lesser differences were noted in the agglutinogenic activity of the Vi antigen, and none in its agglutinin-binding capacity.

2. Treatment with alcohol altered the TVi antigen of one of the species (Bact. coli5396/38) in a way different from that seen in the other three species.

3. On the other hand, dilute acid or alkali produced the same chemical changes in the TVi antigen of all four Bacteriaceae.

4. The TVi antigen present in the four Bacteriaceae appears to be one and the same substance; it cannot be differentiated by the customary serological methods. Its different physico-chemical state after exposure to heat or alcohol is, therefore, conditioned by other constituents of the bacterial cell, which may, or may not, be antigenic.

5. The simultaneous O- and Vi-inagglutinability resulting from heating at 75° C. is particularly impressive since it does not appear to be specially related to any one of the known antigenic components.

6. These findings invalidate the basis on which the L, A and B antigens ofBact. colihave been differentiated.

7. There is also no valid reason for designating the labile somatic antigens ofSalmonellaand other Bacteriaceae as K antigens. These antigens have the general characters of the Vi antigen ofSalm. typhi, are demonstrated by methods developed in the study of the typhoid Vi antigen, and are not associated with typical capsules.

8. The M (mucoid) antigens ofSalmonellaand ofBact. coliare in many respects different from the Vi antigens and should be classified separately.

I gratefully acknowledge the valuable technical assistance received from Mr F. J. Flynn throughout the work reported in this and the preceding papers of this series.
Experimental infection of human volunteers with the U-virus—A strain of ECHO virus Type 11
Authors: Buckland F. E. , Bynoe M. L. , Philipson L. , Tyrrell D. A. J.
Published: May 2009

Re-examination of the U-virus of Philipson & Wesslén has shown it to be a typical ECHO virus closely related to Type 11 of this group. Ultrafiltration and ultra-centrifugation techniques indicate that the virus particle has a diameter of about 27 mν and serological studies confirm its antigenic relationship to the ECHO group.

The virus has been successfully transmitted via the nasal route to volunteer adult subjects. All of them became infected but the clinical picture showed no more than a very mild gastro-intestinal illness or a slight disturbance of the general well-being.

Passage in monkey kidney cells appeared to attenuate significantly when compared with short-term passage in human embryo-lung culture, and this seemed to affect the isolation rate from subjects so infected.

The virus is highly immunogenic. Antibodies to the U-virus have been found in normal persons residing in Great Britain.

We wish to thank the volunteers for their willing co-operation and Miss J. B. Macdonald for help with the clinical observations. Dr A. D. Macrae supplied the ECHO Type 11 prototype virus and immune serum and Prof. C. H. Stuart-Harris supplied the pooled human sera. The Director, Microbiological Research Establishment, Porton, afforded the use of the ultracentrifuge. Monkey kidneys were supplied by the M.R.C. polio vaccine control laboratories. Mr M. C. Brebner and Miss P. K. Pearce assisted with the laboratory work.
The distribution of salmonella agglutinins in sera of healthy adults at Ibadan
Authors: Collard Patrick , Sen Ranjit , Montefiore David
Published: May 2009

The distribution of salmonella agglutinins among 2117 normal sera from 1054 male and 1063 female adult population of Ibadan is described, and the relation of the distribution of the agglutinins with the antigens of salmonella strains isolated over 2-year period in a hospital in Ibadan, Nigeria, is discussed.

We wish to thank Prof. B. G. T. Elmes and Dr J. B. Lawson for their help with the collection of specimens. Our thanks are due to Mr R. J. Leeming, F.I.M.L.T. for his technical assistance.

(Part of the material upon which this paper is based is included in a thesis for submission for the Cambridge M.D. degree by one of us (D.M.).)
Factors affecting the development of the carrier state in leptospirosis
Authors: Faine S.
Published: May 2009

The growth curves of young mice experimentally infected with L. australis A, L. australis B, L. grippotyphosa or L. icterohaemorrhagiae fell into two types, a ‘lethal’ pattern of continued weight loss until death, or a ‘carrier’ pattern of retardation of weight gain. The ‘carrier’ pattern could be changed to the ‘lethal’ by increasing the size of the infecting dose of a given serotype, or vice versa. Infection with L. icterohaemorrhagiae in newborn mice was fatal, while adults became carriers; susceptibility to infection with L. australis B decreased with increasing age.

The numbers of infecting leptospirae and the age of the mouse determined the outcome of infection with a given serotype in a standard test animal. The basis of species susceptibility is unknown, but it is suggested that variation in the ability to produce lesions is the basis of the differences in virulence between serotypes. The ‘host of election’ in leptospirosis is regarded as the result of a quantitative rather than qualitative adaptation of host and parasite to one another.
Efficacy of fluorescent antibody methods for detection ofPasteurella pestisin carcasses of albino laboratory mice stored for various periods
Authors: Hudson Bruce W. , Quan Stuart F. , Kartman Leo
Published: May 2009

Fluorescent antibody techniques were used for detection of plague antigens in infected mouse carcasses stored at 4°–5° C., 20°–25° C. (room temperature) and 370° C. for periods as long as 340 days in certain cases. Tissues of two guinea-pigs infected withPasteurella pestiswere examined after 7 years storage at room temperature. The efficacy of the fluorescent antibody test was compared with blood agar plate culture and animal inoculation during periods in which viable plague bacilli were presumed to be present, and compared with Larson's modified Ascoli test for the presence of soluble plague antigens during periods in which plague bacteria were presumed to be non-viable.

Fluorescent antibody tests were superior to animal inoculation or cultural methods in detection ofP. pestisantigens in mouse carcasses stored for 4 days or longer at 37° C., for 8 days or longer at 20°–25° C. (room temperature), and for 34 days or longer at 4°–5° C. Upon examination of specimens presumed to lack viable plague organisms the fluorescent antibody test and precipitin tests were approximately equal in efficiency for detection of plague antigens in carcasses stored for 16–82 days at 37° C. and for 16–82 days at 20°–25° C. Ten of 21 mice stored for longer periods (140 and 340 days) at 4°–5° C. were negative by precipitin tests, whereas 19 of the same 21 rodents were positive by fluorescent antibody tests. In addition, after 7 years storage at room temperature tissues of two plague-infected guinea-pigs were negative by Larson's modified Ascoli test but positive by the fluorescent antibody test.
Comparative studies onSalmonella typhigrownin vivoandin vitroII. The effect of extracts from normal and infected organs on the bactericidal serum action on strains grownin vivoandin vitro
Authors: Olitzki A. L. , Kaplan Ophira
Published: May 2009

The sensitivity ofin vitro- andin vivo-grown strains ofS. typhiwas determined not only by their antigenic structure, but also by their growth phase. An increased vulnerability to the antibody-complement system has been found in cells during the lag and the early exponential phase, while non-multiplying cells devoid of any nutrient were almost invulnerable to the antibody-complement system. Extracts of organs from normal and infected animals may promote the growth ofS. typhi, and, therefore, increase its vulnerability to the antibody-complement system. The majority of extracts from organs of mice infected with strain Ty 2 inhibited markedly the bactericidal action of serum on this strain and, to a lower extent, on strain O 901.
Sources of staphylococcal infection in surgical wound sepsis
Authors: Bassett H. F. M. , Ferguson W. G. , Hoffman E. , Walton M. , Blowers Robert , Conn Connie Alderson
Published: May 2009

1. In two hospitals, post-operative staphylococcal wound sepsis occurred with equal frequency in patients who were and in those who were not nasal carriers of Staph. aureus.

2. Nasal carriage of Staph. aureus was not always associated with skin carriage at the site of operation, but even patients who were skin carriers suffered no more sepsis than non-carriers.

3. Self-infection was a less frequent cause of sepsis than was cross-infection. Other investigations of this type have revealed conflicting findings on the frequency of self-infection. These may be due to differences in the epidemiological properties of staphylococci infesting the hospitals; to different methods of preoperative skin preparation; and to the different types of operation concerned.

4. In one of the hospitals, 31% of probable operating-room infections were with organisms similar to those carried by some member of the surgical team. In infections thought to have occurred in the ward, only 10% showed this similarity. In 11 of 35 presumed operating-room infections, the source may have been a member of the surgical team.

For help and co-operation we are grateful to Mr G. A. Mason, Senior Surgeon, Newcastle Regional Thoracic Surgery Service; and Dr Joan Millar, Miss G. Jones, Miss E. Smith, Mrs Jean Best, Miss Winifred Mahon, Dr K. Hodgkin, Dr W. Stewart, Mr S. Griffin, Mr W. C. Barnsley, Mr R. Dobson, Mr W. H. Bound, and many nurses and other hospital workers. Our especial thanks are due to Professor R. E. O. Williams, who phage-typed many of the staphylococci, and then taught us to do this for ourselves.
The incidence of natural Clostridium welchii α-antitoxin in Indian equines: its influence on the results of antigenic stimulus
Authors: Basu P. N. , Roy R. N.
Published: May 2009

Presence of natural Cl. welchii α-antitoxin in 65 Indian equines was observed. All the 65 equines had 1 unit or more of circulating natural antitoxin per ml. of serum. The maximum titre observed was 4 units/ml. in about 8% of the animals. These figures are very much higher than the figures obtained in other countries. Such a high incidence of natural immunity indicates frequent natural contact with the antigen concerned.

Results of hyperimmunization of 7 equines are recorded and discussed.

Our thanks are due to the authorities of Bengal Immunity Laboratory for permission to publish these observations and to Sri M. Pal for useful technical assistance.
The size distribution of airborne particles carrying micro-organisms
Authors: Noble W. C. , Lidwell O. M. , Kingston D.
Published: May 2009

Values are given for the median equivalent diameters and for the inter-quartile range, of airborne particles carrying a variety of micro-organisms.

Organisms associated with human disease or carriage were usually found on particles in the range 4–20 μ equivalent diameter.

Many fungi appeared to be present in the air as single spores.

We should like to acknowledge the collaboration of Dr Yvonne M. Clayton in the collection and examination of the fungal samples.
The typing of enteroviruses in tissue culture by neutralization with composite antiserum pools
Authors: Hambling M. H. , Davis Patricia M. , Macrae A. D.
Published: May 2009

A scheme is described for the identification of enteroviruses in tissue culture by neutralization with composite antiserum pools. The method for making these pools is given. Antisera to twenty-seven enteroviruses were included in the pools which were used to examine 115 viruses consisting of ninety-eight recently isolated viruses and seventeen prototype strains. The results indicate that this scheme provides a useful screening method for identifying enteroviruses. It has proved to be practicable, time saving and very economical in tissue culture.

We are grateful to Dr C. M. P. Bradstreet who made available some of the rabbit antisera.
A comparative study of susceptibility of primary monkey kidney cells, Hep 2 cells and HeLa cells to a variety of faecal viruses
Authors: Pal S. R. , McQuillin J. , Gardner P. S.
Published: May 2009

A comparative study of the susceptibility of monkey kidney, Hep 2 and HeLa cells to enteroviruses and adenoviruses is made. It seems that this Hep 2 cell line is as effective as the monkey kidney cells in their susceptibility to vaccine strains of polioviruses and far better than monkey kidney cells in their susceptibility to strains of ECHO 6 and ECHO 11 from clinical material. It is as effective as, or slightly better than, HeLa cells for the isolation of adenoviruses. It also compares favourably with monkey kidney cells for the isolation of other enteroviruses.

We are most grateful to Glaxo Laboratories Ltd. for the supplies of monkey kidney cells used in this investigation.
Lizards as vectors of human salmonellosis
Authors: Hamel F. A. de , McInnes Helen M.
Published: May 2009

Human infections withSalmonella saintpaulhave become more frequent in New Zealand in recent years. Most cases now occur in Otago. It is shown that wild lizards in Otago, particularly the common skink (Leiolopisma zelandica), carryS. saintpauland that most if not all human outbreaks of this salmonella serotype are associated with either lizards or lizard infested areas. So far as is known this is the first report incriminating lizards as the probable cause of human salmonellosis.
Mosquito-borne infections in Fiji: II. Arthropod-borne virus infections
Authors: Maguire T. , Macnamara F. N. , Miles J. A. R. , Spears G. F. S. , Mataika J. U.
Published: May 2009

Surveys of arbovirus activity in Fiji were conducted over a 10-year period from December 1959 to December 1969. No arboviruses were isolated from over 200,000 mosquitoes, 9000 ticks, or 575 serum samples. Eight thousand human and 1117 bird, bat and animal sera were tested for haemagglutination-inhibiting arbovirus antibody using a variety of group A, group B and Bunyamwera group antigens. Only a small number of low-titre reactions were found among the non-human sera, but 14% of all human sera were found to contain Group B antibody. The antibody prevalence increased with increasing age, from less than 1 % for persons born since 1950, to 70% for persons born before 1900. The age differences in prevalence could be used to estimate the time and size of previous epidemics. Differences were found in antibody prevalence between the sexes, between ethnic groups and between persons from different regions. These differences could be explained in terms of climate, location and custom.

Historical and serological evidence both suggest that all the antibody detected was due to past exposure to dengue virus. The very high proportion of the population with no dengue antibody makes Fiji a high-risk area for a further dengue epidemic. Dengue virus is known to be active in the Pacific and South-East Asia.
Postnatal decline of maternally acquired viral antibodies of different specificities
Authors: Cloonan M. J. , Hawkes R. A. , Stevens L. H.
Published: May 2009

The rates of decline (half-lives) of maternally acquired antibodies of two different specificities in a group of infants were found to be highly variable, ranging from 18 to 192 days for parainfluenza type 3 antibody (54 infants) and from 15 to 251 days for influenza A2 antibody (nine infants). For antibodies of both specificities approximately 75% of the half-lives were between 15 and 60 days. With parainfluenza type 3 antibody, and possibly with influenza A 2 antibody, the half-lives were inversely proportional to the initial antibody titre of the babies' sera. This relationship could be described by a rectangular hyperbola. Babies with high antibody titres at birth lost this antibody rapidly whereas in babies with low initial titres antibody declined over a longer period.

The half-lives of parainfluenza type 3 antibody and influenza A 2 antibody were compared with that of rubella antibody in the same group of infants (previously published). Maternally acquired viral antibodies of different specificities did not necessarily decline at similar rates in any given child. In nine infants, maternally acquired antibodies of two different specificities (rubella and parainfluenza type 3) declined at significantly different rates in the same child. It is suggested that although the half-life of antibody of a given specificity is related to its concentration in the serum, it is independent of the level of serum antibodies of other specificities.
Cytomegalovirus antibody production in renal transplant patients
Authors: Nagington J.
Published: May 2009

Sera were examined from 50 patients on the renal transplant unit, Cambridge, for antibody against cytomegalovirus by complement fixation and by immuno-fluorescence for IgG and IgM antibodies.

The incidence of antibody on admission was 84% with a possible further 8% so that nearly all had been infected at some time by CMV.

43 (86%) patients showed evidence of active infection after admission, 39 by serology and four only from the examination of post-mortem material.

Twenty-one patients produced IgM antibody and production was prolonged for years in patients that survived. Antibody production was related both to transplantation and admission to hospital.

The evidence indicated that primary CMV infections were rare, that IgM anti-body production was the result of active infection and that this could be attributed to reactivation without the need to invoke re-infection as the source although this type of patient is both susceptible and exposed to re-infection.
The survival of salmonellas on finger-tips and transfer of the organisms to foods
Authors: Pether J. V. S. , Gilbert R. J.
Published: May 2009

The survival of salmonellas on the finger-tips is considered with reference to the ease with which they can be transferred to food by handling.

Escherichia coliand severalSalmonellaserotypes were shown to survive on the finger-tips for various periods of time, for example,S. anatumcould be recovered 3 hr. after artificially contaminating them with between 500 and 2000 organisms.S. anatumcould also be recovered from the finger-tips after contaminating them with more than 6000 organisms followed by a 15 sec. hand-wash 10 min. later. Similarly, the survivors from minimal inocula of less than 100S. anatum/finger-tip were, after 10 min., still capable of infecting samples of corned beef and ham.E. coliwas isolated from the finger-tips of 13 of 110 butchers soon after they had left the meat line at a meat products factory, but was not detected on the finger-tips of 100 volunteers at the Central Public Health Laboratory.

The implications of the present findings to the spread of salmonellas from raw to cooked foods, and the relevance of this to outbreaks ofSalmonellainfection in the general population and in hospitals, are discussed.
An epidemiological study of the incidence of salmonellas in pigs
Authors: Ghosh A. C.
Published: May 2009

The incidence of salmonellas in pigs was studied in five farms and a bacon factory.

Persistence and spread of salmonella excretion in pigs in a breeding establishment is described. Salmonella excretor boars and sows were responsible for the spread and perpetuation of infection in the farm. The possibility of spreading salmonella infection between farms through the distribution of excretor pigs was studied. Infection persisted and was related to the initial state of excretion of the pigs while at the farm of origin.

The importance of feeding stuffs as a source of salmonella infection in pigs is discussed. Specially prepared heat treated pellets fed to the pigs prevented the introduction of salmonellas.
A comparison of the antigens present on the surface of virus released artificially from chick cells infected with vaccinia virus, and cowpox virus and its white pock mutant
Authors: Baxby Derrick
Published: May 2009

Antisera prepared against vaccinia and cowpox viruses were absorbed with purified suspensions of vaccinia virus, red cowpox and white cowpox viruses. They were then tested for their ability to neutralize the viruses, and to precipitate the virus soluble antigens.

The results showed that some virus specific antigens were not virus surface components and that some components were present on the surface of all three viruses. However, certain components were detected on the surface of vaccinia virus but not on the surface of cowpox virus, and vice versa. Some evidence for the existence of a vaccinia-specific surface component was also obtained.

Comparisons between results of cross-neutralization tests and immunodiffusion tests on the absorbed sera indicated that antibody to a number of antigens, including the classical LS, and the cowpox-specificdantigen play no part in the process of poxvirus neutralization.
Age, time and cohort factors in mortality from cancer of the cervix
Authors: Barrett J. C.
Published: May 2009

Data for mortality from cancer of the cervix in England and Wales by 5-year age groups and four quinquennia (1951–70) are analysed. The logarithms of the mortality rates are regressed on age group, epoch of death and epoch of birth. The factors obtained are considered in relation to particular features of the mortality pattern, such as the reversal of trend in certain age groups.
Phage typing of coagulase-negative staphylococci and micrococci
Authors: Dean Beverly A. , Williams R. E. O. , Hall Felicity , Corse Jean
Published: May 2009

A total of 3217 strains of coagulase-negative staphylococci and micrococci were tested for susceptibility to a collection of phages isolated from coagulase-negative cocci; it was concluded that a useful typing scheme could be developed. Of the strains of Baird-Parker's biotype 1, 72% were lysed by one or more phages, although rather a large proportion of strains are lysed by many phages to give a complex typing pattern.

Normal persons commonly yield 10 or more distinguishable strains of coagulase-negative cocci in cultures from the nose and the skin.
Reactions to tetanus toxoid
Authors: White W. G. , Barnes G. M. , Barker E. , Gall D. , Knight P. , Griffith A. H. , Morris-Owen R. M. , Smith J. W. G.
Published: May 2009

In a factory population the occurrence of reactions to tetanus toxoid was recorded after 6740 injections. The incidence of general reactions was 0·3 % and of local reactions 2·6%. The local reaction rate to the first injection of the basic immunization course was 0·9%, to the second injection 2·7%, and to the third injection 7·4%. To booster injections the rate was 1·6%. The local reaction rate was appreciably higher in women than in men – 14·4 % and 5·7 % respectively in the case of the third injection – and the incidence among women increased with age.

Tetanus vaccine containing 10 Lf of toxoid caused fewer reactions than one containing 20 Lf, but a reduction in the content of aluminium adjuvant did not affect the reaction rate.

Almost all reactors were found to have a satisfactory serum antitoxin concentration at the time of the reaction or developed a satisfactory immunity within 1–6 months.

Skin tests were made in 32 hypersensitive patients. Neither the diluent, thiomersal preservative, nor the culture medium appeared to be responsible for hypersensitivity. The degree of hypersensitivity elicited by a special highly purified toxoid was only very slightly less than that elicited by the commercially pure toxoid. It is suggested that reactions are largely due to the toxoid antigen itself rather than to impurities or other components of the vaccine.
The nature of the antibody response toYersinia enterocoliticaserotype IX in cattle
Authors: Corbel M. J.
Published: May 2009

The nature of the antibody response of cattle to the antigen ofYersinia enterocoliticaIX cross-reacting withBrucellaspp. was examined. Density-gradient ultracentrifugation, ion-exchange chromatography, antibody adsorption and elution and disulphide bond reduction tests showed that both 19 S IgM and 7 S IgG1and IgG2antibodies were produced in response to the cross-reacting antigen. The highest titres of cross-reacting antibodies were detected by the agglutination and Coombs antiglobulin tests. Production of complement-fixing and precipitating antibodies cross-reacting withBr. abortuswas transient and high titres were not attained.

In contrast, although infection withBr. abortusalso evoked cross-reacting antibodies of the IgM and IgG classes, much higher titres were produced in the complement fixation and precipitation tests and these persisted for long periods. At all stages of the serological response to both organisms, the two infections could be differentiated by the quantitative Rose Bengal plate test.
Enrichment procedures for the isolation of Salmonella, Arizona, Edwardsiella and Shigella from faeces
Authors: Iveson J. B.
Published: May 2009

Strontium selenite A broth incubated at 37° C., and strontium chloride B broth incubated at 43° C., have been found an effective combination for the isolation of Salmonella, Arizona and Edwardsiella from human faeces.

Direct plating on deoxycholate citrate agar was superior to enrichment methods for the isolation of Shigella species.

Strontium selenite A broth was suitable for the isolation of Salmonella and Arizona bacteria at both 37° and 43° C.

Strontium chloride B broth incubated at 43° C. was best for the isolation of Salmonella and Edwardsiella.

Modified bismuth sulphite agar, although superior to D.c. agar for the growth of Salmonella and Arizona bacteria, was unsuitable for Edwardsiella and Shigella species.

A considerable difference was observed in the distribution of Salmonella, Arizona and Edwardsiella serotypes isolated from humans in remote areas, when compared with isolations from more densely populated urban and agricultural centres.

Epidemiological and zoogeographical aspects of host–parasite associations between humans, animals and pathogenic Enterobacteriaceae in Western Australia are discussed.
Variation among strains ofCorynebacterium diphtheriaeduring an outbreak in a restricted environment
Authors: Gibson L. F.
Published: May 2009

Strains ofCorynebacterium diphtheriaeisolated from a small outbreak in the restricted environment of a Mental Hospital were examined. All belonged to one serotype, but there was marked variation in diphthericin type, in sensitivity to bacteriophages and in the minor antigens possessed. One strain was non-virulent and laboratory-produced variants of this non-virulent strain showed changes in some of the characteristics used in the identification and typing of the organism, such as diphthericin type, sensitivity to bacteriophages and diphthericins, virulence, starch fermentation and, to a lesser extent, in antigenic structure. The epidemiological and experimental findings are consistent with the hypothesis that the strains isolated, both in the hospital and in the laboratory, were derivatives of a single parent and the mechanism of some of the variations could be related to changes in some structural component such as the cell membrane or the cell wall.