bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of a cell-wall-defective variant ofBrucella abortusof bovine origin
Authors: Corbel M. J. , Scott A. C. , Ross H. M.
Published: May 2009

The properties of an atypicalBrucellastrain isolated from lymph node tissue of a cow slaughtered as a brucellosis reactor were examined. The organism was Gram negative and highly pleomorphic, existing as cocci, coccobacilli, rods, branched and irregular forms which stained with fluorescent antibody conjugates prepared against rough and smoothBrucella abortusstrains. It produced lecithinase and required at least 15% v/v equine or bovine serum for growth. It did not need supplementary CO2for growth, produced H2S and was inhibited by brucella dyes and partially byi-erythritol. Growth inhibition or lysis was produced by brucellaphages. The organism was not pathogenic for guinea-pigs or mice but evoked antibodies mainly to roughBrucellaantigens.
The use of the milk ring test in a survey of the incidence of bovine brucellosis in southern Scotland
Authors: Ferguson G. S. , Robertson A.
Published: May 2009

A report is made of a total of 438 simultaneous blood serum and milk ring tests, and an attempt made to evaluate the milk ring test as a diagnostic aid in individual animals.

The ring test has been used to test the bulk milk from some 370 herds providing the greater part of the raw milk supply for Edinburgh.

The incidence of viable Br. abortus in raw milk samples taken in the Edinburgh area has been studied together with the ring test reaction of such samples.

The survey has shown that:

(1) The ring test is correct in some 93 % of cases in detecting cows whose blood serum will be found positive to the brucella agglutination test.

(2) The ring test, if carefully carried out, is a simple time-saving and accurate screening test for detecting herds possibly infected with brucella.

(3) A high proportion of herd milks (53 %) giving a positive reaction to the ring test is disclosed, and the probable effect of vaccination with strain 19 in giving rise to this figure is noted.

(4) The relatively high incidence (at least 10·5%) of Br. abortus in Edinburgh milk supplies is noted.

Thanks are tendered to Dr Bruhn of the Veterinary School, and Dr Bendtsen, Veterinary State Serum Institute, both of Copenhagen and to Dr Stableforth of the Ministry of Agriculture and Fisheries Laboratory at Weybridge, for providing samples of stained antigen. Thanks are also due to the Bacteriology Department, Edinburgh University, for providing material from guinea-pigs and for relevant information; to J. Norval, Esq., M.R.C.V.S., for permission to obtain samples from the slaughterhouse, and also to the dairies and farmers who granted facilities for taking samples and to Miss Elma Chapman for assistance in the laboratory studies and in taking samples.
Observations on brucella species based on the examination of 800 strains
Authors: Cruickshank J. C. , Madge B.
Published: May 2009

An account is given of the examination by biochemical and serological methods of 800 strains of brucella sent for identification to the Brucella Reference Laboratory of the Public Health Laboratory Service.

Most of the strains were isolated from milk in Great Britain, but strains from other countries, and from cases of undulant fever, were also examined.

Of 738 strains from milk in Britain, 680 wereBr. abortus, of which sixty-two (9·1 %) were of a type inhibited by all the usual test-dyes in their customary concentrations. Thirty strains ofBr. melitensis, behaving typically in all laboratory tests, were obtained from milk from individual cows, herds or bulk sources.Br. melitensishas now been identified from twenty-four separate farms and one Tuberculin Tested bulk supply in this country. Eighteen strains behaved likeBr. abortusin biochemical tests, but serologically likeBr. melitensis.

Of the relatively small number of strains isolated from patients with undulant fever in Britain, all those from persons infected in this country wereBr. abortus, with the exception of two laboratory infections withBr. melitensis. The organisms isolated in Britain from patients infected abroad comprised three strains ofBr. melitensis, one strain behaving biochemically likeBr. abortusand serologically likeBr. melitensis, and two behaving biochemically likeBr. melitensisand serologically likeBr. abortus. One of the latter was from a patient infected in southern Italy, and the examination of nineteen strains from that country showed that thirteen were of this type. The thionin-resistant type ofBr. abortuswas identified several times, from undulant fever cases in Rhodesia, Kenya and Italy. No strains ofBr. suiswere observed.

I wish to thank the numerous bacteriologists who sent cultures and provided details of their isolation. A few submitted large numbers of strains and enabled a general picture of the prevailing types to be obtained. I am grateful to these and to the other bacteriologists who provided information about the herds from whichBr. melitensiswas isolated, in particular Dr P. H. Martin and Dr J. A. Sykes (Ipswich), Dr L. M. Dowsett (Norwich), Dr J. Kennedy (Newcastle, then at Stafford), Dr J. H. C. Walker (Luton), Dr E. H. Gillespie and Dr N. S. Mair (Leicester) and Dr J. E. Jameson (Brighton). I have also to acknowledge the help of Dr A. W. Stableforth, Director of the Ministry of Agriculture and Fisheries Veterinary Laboratory, who provided much bacteriological and veterinary information about the infected herds.
An intensive system for guinea-pigs
Authors: Lane-Petter W.
Published: May 2009

Guinea-pigs are suited to colony management, whether for breeding or maintenance, and single cages are only necessary when experimental or other requirements demand them.

Floor pens are extravagant of space and open to criticism on grounds of hygiene.

Wire floored pens, in batteries of four tiers, have many advantages, both in economy and hygiene, and are compatible with excellent health and breeding performance.

Certain details in the design of such batteries are important; among them being the size of mesh of the wire floor, the avoidance of corners and ledges where soil can accumulate, and the observance of convenient dimensions.

I first saw this method developed by an accredited guinea-pig breeder, Mr Ashton Poole, who has since given up breeding. Although the present battery is a far cry from Mr Poole's pens, the method is the same, and the unblemished health record of his very large stud over a period of some years was impressive. I am glad therefore to acknowledge my indebtedness to him.
Experiments with the Cyprus strain of blue-tongue virus: multiplication in the central nervous system of mice and complement fixation
Authors: van den Ende M. , Linder Anne , Kaschula V. R.
Published: May 2009

The multiplication rate of blue-tongue virus in suckling and adult mouse brains has been determined. The first cycle of virus multiplication appears to take 8–12 hr. both in fully susceptible sucklings and in adults which suffer an inapparent infection with this virus.

Antigens suitable for complement-fixation tests have been made from suckling mouse brains and from eggs infected with blue-tongue virus.

A potent immune serum has been obtained from mice immunized by repeated intraperitoneal injections of blue-tongue virus in suckling mouse brain.

Attempts, with negative results, have been made to demonstrate interference with virus multiplication by virus from eggs incubated at 38·5° C. and by virus from adult mouse brains.

We are grateful to Dr R. Alexander for his helpful and critical interest in this work and to Mr G. S. Turner and Dr G. Selzer for their able and willing assistance.

The Virus Research Unit is financed by the South African Council for Scientific and Industrial Research and by grants from the Nkana-Kitwe and Chingola Poliomyelitis Research Funds.
The carriage of Staphylococcus pyogenes var. aureus in the human nose
Authors: Gould J. C. , McKillop Elizabeth J.
Published: May 2009

Over 500 medical students have been examined for nasal carriage of Staph. pyogenes at weekly intervals over a period ranging from 3 to 12 months.

Nasal carriers were classified as persistent, intermittent and occasional. Of the students, 39% were persistent or intermittent carriers in whom the staphylococcus was believed to colonize the skin of the vestibule of the nose; 42% were occasional carriers in whom the staphylococcus was only a chance inhabitant of the nares.

Staph. pyogenes was isolated from the anterior nares of persistent carriers on at least 90% of the occasions on which they were examined, and was of the same phage type on each occasion. From intermittent carriers it was isolated less regularly, but on at least 10% of occasions on which they were examined, and it remained of one phage type. Staph. pyogenes was isolated at less than 10% of swabbings from occasional carriers, and at each the organism was of a different phage type.

Eighty-nine per cent of persistent and intermittent carrier strains, and 54% of occasional carrier strains could be typed with phage filtrates. The strains not typable with phage filtrates, and found predominantly among occasional carriers, were considered worthy of separate classification, and it is suggested that typability with phage be used as a criterion of pathogenicity for Staph. pyogenes.

We wish to thank Prof. T. J. Mackie for his continued interest and advice; Dr J. P. Duguid for criticism and advice; Dr R. E. O. Williams and Miss Joan Rippon of the Staphylococcal Reference Laboratory, Colindale, who very kindly instructed one of us (J.C.G.) in bacteriophage typing; Dr Donald Cruickshank for taking nasal swabs from patients; Dr Cumming of the Blood Transfusion Department, Royal Infirmary, Edinburgh, for permission to swab blood donors, and the medical students who so willingly co-operated in this work.
The epidemiology of infection withPseudomonas pyocyaneain a burns unit
Authors: Lowbury E. J. L. , Fox Jean
Published: May 2009

A bacteriological study of burned patients and of the staff and environment in a burns unit was made with the purpose of discovering the principal reservoirs and routes of transfer ofPs. pyocyanea.

Infected burns appeared to be the most important reservoirs. About 3 % of the stools of normal subjects and of patients with intestinal symptoms carried the organism, which was also isolated from the nose, throat, nasopharynx, skin and ear of a small proportion of patients and staff in the burns wards.

The hands of nurses in the wards were often contaminated withPs. pyocyanea, and presented a likely vector in the transfer of the organism by contact—e.g. from the bandages of infected patients, and from furniture and other objects near to their beds.

It was shown by slide agglutination that a new type ofPs. pyocyaneaadmitted to one of the wards spread freely in that ward but hardly at all to the other ward. Since patients from both wards used the same dressing station and operating theatres, it seemed from this finding that a large proportion of the cross-infection occurred in the wards.

Polymyxin dusting powder was shown in a controlled trial to protect exposed burns against contamination byPs. pyocyanea.

These results are discussed in relation to the mechanism of transfer of the organism and the methods of preventing cross-infection. The need to use several methods concurrently is emphasized, since none of those which have been investigated contributes more than a partial effect. Cubicle wards are advocated, since much cross-infection is shown to occur in open wards.

We are much indebted to Dr G. T. Cook for kindly letting us use results obtained by him at the Oxford Public Health Laboratory. We also wish to thank Prof. J. F. D. Shrewsbury of Birmingham University and our colleagues at the Birmingham Accident Hospital for their valuable co-operation, and Dr A. C. Cunliffe of King's College Hospital for information on the typing ofProteusfrom patients in our wards.
The poliomyelitis epidemic of 1937 in Denmark: Epidemiology and clinical statistics
Authors: Henningsen E. Juel , Rasch G.
Published: May 2009

The poliomyelitis epidemic of 1937 in Denmark was investigated by means of information obtained about each individual case.

It occurred in the usual season, culminating in September. The districts involved were limited largely to Zealand, including Copenhagen. It is of particular interest that the disease occurred also in rural districts that were the sites of similar epidemics in 1933 and 1934.

It is noted as a peculiar fact that poliomyelitis seems to be unable to invade the whole of Denmark within one season.

The 1937 epidemic comprised 1200 notified cases, of whom 599 developed paralysis and 113 died. Everything suggests that the number of non-paralytic cases was far greater than the number of cases notified. Influenza and angina were notified with striking frequency in the districts where poliomyelitis prevailed.

The morbidity, frequency of paralysis and mortality were greater among males than among females.

A change in the age distribution during the past 35 years is pointed out. In 1937, 30% of the patients were over 15 years, and about 14% over 20 years; of those who died 45% were over 15 years, 20% over 20 years.

Convalescent serum was not employed in Copenhagen, but in the provinces 489 patients were treated with, and 400 without, serum. The principles of the treatment were the same as in 1934. Serum was given early in the disease, as a rule intravenously.
The bactericidal action of ultra-violet light
Authors: Lea D. E. , Haines R. B.
Published: May 2009

Experiments on the bactericidal action of ultra-violet light have been made to determine the shape of the survival curve and the dependence upon radiation intensity of the rate of death.Bact. coli, Bact. prodigiosumand spores ofB. mesentericuswere irradiated with approximately monochromatic light of wave-length 2537 A. The survival curves obtained were exponential and the rate of death was accurately proportional to the intensity over an intensity range of 500:1.

By comparing these results with data previously obtained of the action of X-rays on the same organisms it was established that one ionization produced by X-rays is as effective as some hundreds of ultra-violet quanta. This is interpreted to mean that the quantum yield in whatever chemical change leads to the loss of viability in the irradiated bacteria is, for 2537 A., between 0·01 and 0·001.
The pleuropneumonia-like organisms: further comparative studies and a descriptive account of recently discovered types
Authors: Klieneberger Emmy
Published: May 2009

1. The four different L1 strains in the writer's possession isolated between 1933 and 1936 have been maintained for a further period without reverting to Streptobacillus moniliformis. The supposition that the L1 is a pleuro-pneumonia-like organism and lives in symbiosis with a bacterium in cultures of S. moniliformis is still maintained by the writer and the reasons for it are given.

2. From a culture isolated from lesions in guinea-pigs and pathogenic for these animals called the “guinea-pig strain”, an L1-like organism of the pleuropneumonia group has been separated, but not yet been maintained for a long enough period to ensure irreversibility. The morphology of the “guinea-pig strain” shows that it is closely related to S. moniliformis though it can be distinguished from the latter by its cultural and pathogenic properties. The morphology of two other cultures, viz. a saprophytic coccus from the skin of a pig and the organism known as Fusobacterium nucleatum, have been described as possibly representing similar symbiotic associations of bacteria and pleuropneumonia-like organisms.

3. Cultural and serological differences between the L4 causing arthritis, swollen glands and abscesses in rats, and the two other pleuropneumonia-like organisms from rats, L1 and L3, are recorded. It has been shown that the organisms occurring in the brains of mice, L5 and L6, and in the joint of a mouse, “M55”, are of aetiological significance for the condition in which they occur. At the same time they differ in their colony type, morphology and serological features.

4. Morphological and serological studies of the saprophytic organisms of the pleuropneumonia group isolated by Laidlaw & Elford and Seiffert from water and soil show that Seiffert's organisms are closely related to Laidlaw & Elford's type “A”. In agreement with Laidlaw & Elford it was found that their type “B” is slightly different from “A” serologically, while “C” is distinct from “A” and “B” and may be regarded as a special type.

These saprophytic types are not antigenically related to the parasitic varieties.
The distribution and significance of typhoid Vi agglutinins in normal sera of African natives
Authors: Davis L. J.
Published: May 2009

1. 656 samples of sera taken at random from natives in Southern Rhodesia were examined for the presence of typhoid Vi agglutinins.

2. Forty-nine or 7·47% were shown to contain Vi agglutinins in titres of 1 in 5 to 1 in 12·5.

3. Samples of faeces and urine from twenty-six of the positive Vi reactors were cultured for Bact. typhosum, which was isolated from only one individual who was shown to be a chronic urinary carrier.

4. The significance of these findings is discussed.
The use of hypochlorites for aerial disinfection
Authors: Baker A. H. , Finn S. R. , Twort C. C.
Published: May 2009

A commercial preparation of sodium hypochlorite dispersed in the form of a mist has been tested for germicidal action on bacteria suspended in the air.

The relative merits of acid, neutral and alkaline solutions have been discussed.

A maximum of efficiency dependent on dilution has been shown to exist, and experiments with water and glycerol as diluents have been performed.

The value of hypochlorous acid gas and chlorine as aerial bactericides has been tested, and experimental evidence advanced to show that while these are to some extent effective as gases, the acid, at any rate, is more lethal in solution as a mist.

Further evidence of the importance in aerial disinfection of size and evaporation rate of mist particles has been obtained.

Objections have been raised to the proprietary use of the preparation on account of the liberation of chlorine, and its high salt content, but the necessity for the presence of a certain amount of salt has been shown.

Decrease in germicidal activity of the mists when required to sterilize atomized salivas has been indicated.

The active persistence of sodium hypochlorite mists has been shown to be short.

A few notes on the use of ultra-violet light and nitration methods for combating aerial infections have been added.

It was found that the greater part of a magnesium oxide smoke inhaled by mice was retained in the upper respiratory passages.
Nosocomial infections in children's wards
Authors: Wright Joyce
Published: May 2009

1. During a period of 1 year the incidence of infection with haemolytic streptococci was determined among children on admission to, and during residence in, the children's wards of University College Hospital, London.

2. The increased incidence among those in residence, 13·1% of whom acquired haemolytic streptococci during their stay, was due principally to outbreaks of infection by these organisms. By the slide agglutination method the majority of strains could be assigned to one or other of Griffith's thirty types and the presumed path of their spread studied.

3. The source of the infection in most of the outbreaks was not ascertain-able from the data collected, but in general it did not appear to be in the patients themselves.

4. With a few exceptions, isolation by cubicles was an effective measure in preventing the spread of haemolytic streptococci.

5. In general the haemolytic streptococci seemed to spread from patient to patient, though the exact mode of spread was not ascertained.

6. The clinical manifestations of infection by any one type of haemolytic streptococcus was varied, e.g. wound suppuration, sore throat, pyrexia, otitis media. Many of the infections were “latent”.

7. In addition to the haemolytic streptococcal outbreaks, there were two outbreaks of diphtheria (fifteen patients), two of Bact. sonnei dysentery (ten patients and one nurse), one of catarrhal jaundice (one patient and three nurses), six cases of intercurrent gastro-enteritis of infancy and one case of measles.

8. In all, at least 104 (or 18·9%) of the 551 patients of these wards developed intercurrent infections, manifest or latent, during their stay in hospital.
Inoculation and immunity experiments on calves with the vole strain of acid-fast bacillus
Authors: Griffith A. Stanley , Dalling T. , Pagel W.
Published: May 2009

Both controls became infected, the glands of the alimentary tract showing widespread lesions and some dissemination, slight in one, a little more extensive in the other.

Of the nine vaccinated calves, five were found to have trivial tuberculous lesions in the glands adjoining the alimentary tract and four showed no macroscopic lesions, either in the glands of the alimentary tract or elsewhere.

Living bovine tubercle bacilli were not present in emulsions of mesenteric or thoracic glands of two of the four no-lesion calves and were demonstrated in the mesenteric glands but not in a bronchial gland of a third. The pooled glands of the fourth no-lesion calf caused general tuberculosis in two guinea-pigs.

Living bovine bacilli were very sparse in the thoracic glands of two of the calves with trivial lesions in the head or mesenteric glands and were not present in a bronchial gland of a calf which showed a few foci in the mesenteric glands.

Living bovine bacilli were present in lymphatic glands of one calf, but which were the glands that contained them could not be stated, as these were pooled before injection. The mesenteric glands only of the remaining calf were tested and proved infective.

No lesions were found after single vaccinations in three instances (two intravenous and one subcutaneous) and after two vaccinations in one instance, the periods between the single vaccinations and the resistance tests ranging from 2 to 6 months. There seems no advantage, therefore, in giving more than one dose of vole bacilli. The intravenous is, however, preferable to the subcutaneous method, because the former method does not produce an unsightly local lesion.
Seasonal fluctuations of the vitamin A and C content of Palestinian milks
Authors: Guggenheim Karl
Published: May 2009

1. The vitamin A and vitamin C contents of Palestinian fresh milk from three different sources were determined at regular intervals during the period February 1938 to March 1939. Between October 1938 and March 1939, these contents were also determined in Jerusalem pasteurized milk.

2. The carotene and vitamin A content of Palestinian milk corresponds to that of American and European stable milk. This is due to insufficiency of green fodder in the diet of Palestinian cattle.

3. Emek milk from the Valley of Jezreel contains more carotene and vitamin A than does the Kiryath Anavim milk from a hill district, owing to the better supply of green fodder in the valley. Milk from a Jerusalem dairy contains less carotene and vitamin A than does the milk from the nearby Kiryath Anavim settlement.

4. All the milks examined show seasonal fluctuations in the carotene and vitamin A content. These variations are in direct relation to the supply of green fodder. The secretion of carotene begins to increase in January to April, according to the source of the milk, and begins to fall in August.

5. The average percentage of carotene to the total vitamin A substances (carotene and vitamin A) ranges between 38 and 50. The ratio carotene to total vitamin A varies seasonally and otherwise in accordance with the total vitamin A in the milk.

6. The vitamin C content of Palestinian milk lies in the same range as that of European and American milks.

7. All milks examined contained considerably more vitamin C during the second than during the first half of the year with a peak in June and July. This increase does not seem to bear any relation to feeding practice.

8. The losses of vitamin A and vitamin C found in pasteurized milk correspond with those given by European and American authors.

9. Transportation of milk over long distances may cause almost complete loss of vitamin C.
The neutralization of pox viruses II. Relationships betweenvaccinia, rabbitpox, cowpox and ectromelia
Authors: McNeill T. A.
Published: May 2009

Plaque neutralization on HEp 2 cells was used to determine the relationship between vaccinia, rabbitpox, cowpox and ectromelia using both 7 S and 19 S antibody. It was shown that for the strains of virus used vaccinia and rabbitpox were very similar but cowpox and particularly ectromelia were clearly distinguishable. The cross-titration relationships were the same for 7 S and 19 S antibody.

The titration slopes and kinetics of cross-neutralizations were interpreted on the basis of a hypothesis of antibody competition put forward in the preceding paper. It was tentatively concluded that these four viruses share a common critical antigen for neutralization and that differences in the structure or presentation of neighbouring antigens could give rise to some of the observed effects.
Antistreptolysin O titres amongst children in a rural area of Ceylon
Authors: Gunatillake P. D. P. , Perera T. D. S.
Published: May 2009

Antistreptolysin O titres in the sera of children in a rural population of Ceylon were determined, to establish the upper limit of the normal ASO titres in nonrheumatic children, and to compare these ASO titres with results of surveys done in other countries.

Swabs were taken from throats and ulcers of the children examined and cultured specifically for group A haemolytic streptoccoci. Of a total of 257 children, 29·5 % had ASO titres of over 166 Todd units. The greatest number of children showed ASO values between 100 and 166 units. The percentage of children showing values over 166 units increased with age until a maximum of 54 % was reached between 9 and 10 years. Group A haemolytic streptococci were isolated from five throat swabs, but there were no isolations from ulcers. The values obtained from this survey have been compared with those from a few other developing countries.
Growth in chick chorioallantoic membranes of strains of Newcastle disease virus of differing virulence
Authors: Reeve P. , Rosenblum Margaret , Alexander D. J.
Published: May 2009

The growth of eight strains of Newcastle disease virus in chick embryo chorioallantoic membranes was studied by comparing, at different times after infection, the amounts of haemagglutinin released into the allantoic fluid (extracellular haemagglutinin) with that associated with the membrane (cell-associated haemagglutinin). The virulence of the strains examined differed in that some killed chick embryos more rapidly than others. All strains released similar amounts of extracellular haemagglutinin and maximum titres were achieved about 12 hr. after infection. With virulent strains cell-associated haemagglutinin titres increased exponentially until the death of the host and maximum titres were much higher than those of extracellular haemagglutinin. With avirulent strains cell-associated haemagglutinin titres increased exponentially for only a limited time and titres were always lower than the titres of extracellular haemagglutinin.

Similar results were obtained when the titres of neuraminidase and viral ribonucleoprotein were measured during the growth of two virulent and two avirulent strains. Virulence appears to be associated with the continued intracellular accumulation of viral antigens.
The platelet aggregation test in group B arbovirus infections
Authors: Penttinen K. , Saikku P. , Myllylä G. , Brummer-Korvenkontio M. , Oker-Blom N.
Published: May 2009

A new serological method, the platelet aggregation (PA) test, was used to study Group B arbovirus infections, which are often associated with thrombocytopenia. The method is based on the interaction of antigen-antibody complexes with platelets. The PA test was nearly as good as the haemagglutination-inhibition (HI) test for epidemiological studies of tick-borne encephalitis (16 out of 18 HI positive sera) and was superior to the complement-fixation test which was positive in 10 out of 18 HI positive sera. The PA test could be used in the serological diagnosis of Group B arbovirus infection. The titres with the PA test were of the same magnitude as the HI titres, and about ten times higher than the CF titres. Two pairs of dengue haemorrhagic fever sera showed high initial PA titres. The role of immune complexes in the pathogenesis of haemorrhagic fevers is discussed.
Soluble antigens obtained from influenza virus by treatment with non-ionic detergent
Authors: Corbel M. J. , Rondle C. J. M.
Published: May 2009

Highly purified influenza virus was degraded using anionic and non-ionic detergents. Best results were obtained using the non-ionic detergent Triton N101. Tests showed that virus extracts contained neuraminidase and a substance that reacted specifically with rabbit antibody to virus haemagglutinin (specific serum blocking substance). Haemagglutination-inhibiting antibody was produced when virus extracts were inoculated into guinea-pigs. Immunodiffusion tests showed that extracts were complex. Host-specific material was regularly found. Under appropriate conditions S-antigen was detected as a single line pattern component. Two or more virus-specific materials were also present. One of these was probably neuraminidase and the other the specific serum blocking substance.
Distribution of mercury resistance among Staphylococcus aureus isolated from a hospital community
Authors: Hall Barbara M.
Published: May 2009

Results from clinical isolations confirmed that mercury resistance is common among antibiotic-resistant strains of Staphylococcus aureus present in a large general hospital although the correlation is not as high as that found by Moore (1960).

The distribution of mercury-resistant strains among infections and carriers in surgical, medical, obstetric and geriatric patients and staff was studied. Attention was directed to the distribution among carriers since there are fewer extraneous factors operating among them, and a statistical analysis was made on the total number of mercury-resistant strains and the number of non-endemic strains; this latter figure was obtained by subtracting the dominant type 80/81, which is nearly always mercury-resistant and antibiotic-resistant, from the total. Analysis showed the geriatric patients to have a significantly higher proportion of mercury-resistant strains in both cases, and obstetric patients to have a significantly lower proportion when the total number of mercury-resistant strains was considered. Among the surgical, medical and staff categories, no significant difference in proportions could be found although a trend, in that order, of decreasing proportions of mercury-resistant strains present was noted.

In those cases infected on admission with tetracycline-resistant strains, although mercury-resistant strains still predominate, mercury-sensitive strains make a sizeable contribution. This is a reflexion of their dominance in the non-hospital environment.
The effects of UK 2054 on the multiplication of influenza viruses
Authors: Barry R. D. , Davies Patricia
Published: May 2009

The isoquinoline compound UK 2054 prevents the uptake of influenza virus by susceptible cells. Pre-incubation of virus particles with 500μg./ml. UK 2054 at 37°C. for 2 hr. does not reduce virus infectivity. Host cells vary in their responsiveness to the inhibitory effect of UK 2054; virus multiplication is inhibited in chick allantoic cells by lower concentrations than those required to inhibit virus growth in chick embryo fibroblasts. The effectiveness of UK 2054 is reduced by the presence of serum.

It is concluded that inhibition of influenza virus multiplication by UK2054 might result from interaction of the inhibitor with both virus and cells. Any direct combination between inhibitor and virus is completely reversible.
In vitromethod for safety testing of foot-and-mouth disease vaccines
Authors: Anderson E. C. , Capstick P. B. , Mowat G. N. , Leech F. B.
Published: May 2009

The susceptibility of the tissue culture system to small amounts of residual live virus was not influenced by the inactivated antigen present. The depth of inoculum over the cell sheet did not affect results. Negative cultures frequently gave positive first (but not second or later) sub-cultures.

Baby hamster kidney cells were always more sensitive than cattle tongues to infection with any of the strains used.

Confidence in the safety test depends on the number of vaccination doses used; the tissue culture test can be made much more reliable than the cattle test because it is not limited to the 15 ml. of inoculum that restricts the cattle test.
The relevance of the anti-human globulin (Coombs) test and the complement-fixation test in the diagnosis of brucellosis
Authors: McDevitt D. G.
Published: May 2009

The relationship between the serological findings for brucellosis and the epidemiological factors has been studied in veterinary surgeons in Northern Ireland. The anti-human globulin (Coombs) test and the complement-fixation test for brucella were used in two groups of veterinary surgeons, those self-employed and those employed by the Ministry of Agriculture.

Significant serological differences were found to exist between the two groups. Those in private practice showed changes related to age, cattle skin rash, reactions to S. 19 vaccine accidents and symptoms suggestive of brucellosis in the past or the last year. But those working for the Ministry only showed titre changes related to the length of their private practice experience before joining the Ministry. In neither group was there a relationship between serological findings and the type of milk drunk or any particular group of symptoms suggestive of brucellosis.

The findings indicate that high titres to brucella by the Coombs and complement-fixation test can occur in people repeatedly exposed to infection at work. Titres which would be of diagnostic importance in the rest of the population may be of little diagnostic significance even when they are as high as 160 Coombs and 128 complement fixation.
Studies on the 1967–8 foot-and-mouth disease epidemic: The relation of weather to the spread of disease
Authors: Hugh-Jones M. E. , Wright P. B.
Published: May 2009

An analysis of the 1967–8 foot-and-mouth disease epidemic with reference to the initial spread, the origin of outbreaks more than 60 km. from the main epidemic area, the series of outbreaks near Worcester, a specific case history and the daily rate of spread of the epidemic, strongly suggests that the weather played a major part in the spread of disease. The two main factors involved in this type of spread are wind and precipitation. It is noted that after the epidemic had been checked, following anticyclonic weather, the association between the weather and the spread of disease was less apparent.
An adhesive surface sampling technique for airborne viruses
Authors: Thomas G.
Published: May 2009

A mixture of sucrose, glycerol and bovine serum albumin produces a stable coating in a Petri dish which remains adhesive for up to an hour when exposed in a slit sampler. Virus aerosols can be collected on this surface followed the direct addition of cell cultures to demonstrate the presence of viable virus. The technique is applicable to the Andersen sampler. A modified version of this sampler has been produced with the same particle collection efficiency as the standard Andersen sampler. The plaque counts obtained the adhesive surface sampling technique are believed to give an indication of the number of particles collected bearing viable virus.
Observations on the nasopharyngeal carriage of Haemophilus influenzae type b in children in Kampala, Uganda
Authors: Mpairwe Y.
Published: May 2009

Haemophilus influenzae type b was isolated from 4·5% of outpatient children living in various parts of Kampala city and its surroundings. In contrast, this serotype was carried by up to 53 % (average 29 %) of 14 to 18 children living as a group in an orphanage. This finding indicates that the high carriage rate for this serotype demonstrated by Turk (1963) in a group of orphanage infants in Jamaica was not an isolated finding, and that it may be expected where large groups of children live together.

H. influenzae type b did not appear to be a readily transmitted organism even in that group of children with a high carriage rate. This suggests that in ordinary open communities the transmission of this serotype from one household to another may be an extremely rare event.
Bordetella pertussis isolation in general practice: 1977–79 whooping cough epidemic in West Glamorgan
Authors: Kwantes B. W. , Joynson D. H. M. , Williams W. O.
Published: May 2009

Some of the factors influencing the isolation rate of Bordetella pertussis during a whooping cough epidemic in West Glamorgan, Wales, are reported. The organism was isolated from 39% of patients with clinical whooping cough, pernasal swabbing being much more successful than cough plates. Isolation rates were increased in the non-immunized, particularly in the first year of life. Erythromycin and co-trimoxazole significantly reduced the isolation rate of B. pertussis but this did not occur with penicillin. In this study 20 % of patients were culture positive 6 weeks after the onset of their infection. It is suggested that the Department of Health and Social Security recommendation of a minimum period of three weeks exclusion of children from school is inadequate. During the epidemic, the proportion of strains of B. pertussis containing antigen 2 more than doubled.
A study of the specific IgM antibody response inMycoplasma pneumoniaeinfection in man
Authors: Chamberlain P. , Saeed A. A.
Published: May 2009

Sera from 96 patients withMycoplasma pneumoniaeinfection were examined for specific IgM antibody. The complement fixation test was used to measure the IgM after separation by ultracentrifugation through sucrose density gradients. Of patients under the age of 20 years 78 % displayed positive specific IgM titres. In older patients only 34% were IgM positive. The specific IgM remained detectable, but at decreasing levels, during the follow-up period of 5 months. This diagnostic technique appears to be of value in children and young adults experiencing primary infection withM. pneumoniae.
Citrobacter koseri(syn.C. diversus): biotype, serogroup and drug resistance patterns of 517 strains
Authors: Gross R. J. , Rowe B.
Published: May 2009

The namesCitrobacter koseriandC. diversusare synonyms for a species of enterobacterium with a particular ability to cause neonatal meningitis. 517 strains belonging to this species were examined using biotyping and serotyping techniques. 40 % of the strains belonged to serogroups O2 and O1 and 72 % belonged to biotypes d and a. Strains isolated from cerebrospinal fluid belonged to several different serogroups and biotypes but serogroups O2 and O3 and biotypes d and e were the most common. All the strains were resistant to ampicillin, 42 % were resistant to neomycin/kanamycin and 38 % were resistant to cephaloridine. 37 % of the strains were resistant to three or more drugs.
The stability of ergocalciferol in rodenticidal baits
Authors: MacNicoll A. D. , Simpson W. J.
Published: May 2009

Concentrations of the rodenticide ergocalciferol (vitamin D2) in samples of rodent baits laid in foodstores and in the laboratory were monitored over several months. Bait samples were solvent extracted and ergocalciferol concentration determined by high pressure liquid chromatography (HPLC). Ergocalciferol levels were constant for more than 21 days in dry samples and did not fall by more than 30% in 100 days. When water (10% w/w) was added to the baits in the laboratory the ergocalciferol concentration fell by approximately 30 % in 30 days. In these wet laboratory samples there was a rapid visible growth of fungus and in normal rodent control use baits should have been replaced when such deterioration became evident.
Immunogenic variation among the so-called LC strains of Mycoplasma mycoides subspecies mycoides
Authors: Smith G. R. , Oliphant Janet C.
Published: May 2009

Much evidence of immunogenic heterogeneity among the LC strains of Mycoplasma mycoides ssp. mycoides emerged from cross-immunization and hyperimmunization experiments in mice in which three LC strains (Vom/Plum Island, 74/2488, and Mankefår 2833) were used for challenge purposes. All heterologous LC-strain vaccines cross-immunized against the three challenge strains, but protection was usually only ‘partial’, i.e. significantly less than that given by homologous vaccine. Cross-hyperimmunization with all heterologous LC but not SC strains produced protection against challenge with Vom/Plum Island that was virtually ‘complete’, i.e. similar to that produced by homologous vaccine. Challenge with 74/2488 gave generally similar results; but against Mankefår 2833 six heterologous LC vaccines gave complete protection and six did not.

Vaccines prepared from the Smith (1423) strain of M. mycoides ssp. capri gave some protection against Vom/Plum Island but none against 74/2488 or Mankefrr 2833. The cross-immunizing ability of three further M. mycoides ssp. capri strains appeared to resemble that of Smith (1423).

In a cross-hyperimmunization experiment, vaccines prepared from SC strains of M. mycoides ssp. mycoides varied greatly in their ability to protect against challenge with strains 74/2488 and Mankefår 2833.
Comparison of different methods for bacteriocin typing ofKiebsiellastrains
Authors: Simoons-Smit A. M. , Verweij-Van Vught A. M. J. J. , Kanis I. Y. R. , Maclaren D. M.
Published: May 2009

Epidemiological analysis ofKlebsiellastrains from nosocomial infections needs a simple, stable and reproducible technique of typing. We have evaluated three bacteriocin typing methods forKiebsiellaspp. by means of 15 bacteriocin-producing strains, with special reference to stability and reproducibility.

With the three methods indicator strains and clinical strains were retyped on different days under constant test procedures. Stability of bacteriocins was tested by titration immediately after preparation and after 4 weeks of storage at –70°C. Thereafter, reproducibility of typing was tested by means of these freshly prepared bacteriocin lysates and of portions of the same lysates stored at –70 °C. A moderate reproducibility was obtained with one method after two typing experi ments: 79.2% and 61.3% for indicator strains and clinical strains respectively. The other two methods gave a much lower reproducibility of 38 .5% and 32.5 % for indicator strains and of 11.1% and 25.5% for clinical strains after two experiments.

The reproducibility decreased after retyping three, four or five times. These methods are simple to perform but their usefulness for epidemiological studies is doubtful. Possible causes of the lack of reproducibility of the methods are discussed.
The Spread of Bacterial Infection; Some General Considerations
Authors: Topley W. W. C.
Published: May 2009

In a recent series of papers, Flexner (1922), Lynch (1922), Amoss (1922a and b) and Webster (1922a and b) record the results obtained at the Rockefeller Institute in an experimental investigation of epidemics among laboratory animals. These experiments bear a close similarity to those which have been recorded in previous papers of the present series (Topley, 1919, 1921 a and b, 1922 a and b, and Topley, Weir and Wilson, 1921). Their publication affords an opportunity of comparing the results obtained in two independent enquiries, which have been carried out along slightly different lines, and of describing in more detail certain points in the general technique of our own experiments, which have an important bearing on the significance of the results obtained.
The Spread of Bacterial Infection. The Problem of Herd-Immunity
Authors: Topley W. W. C. , Wilson G. S.
Published: May 2009

In our previous studies on the spread of bacterial infection among mice, the resistance of the host has not been especially investigated; although the importance of this factor has been repeatedly referred to in discussing the experimental results obtained.
A further Contribution to the Experimental Study of Epidemiology
Authors: Greenwood M. , Topley W. W. C.
Published: May 2009

In the Goulstonian Lectures, delivered in 1919, one of us (W. W. C. T.) discussed the possibility of attacking epidemiological problems by the method of direct experiment, and reported a few preliminary observations on the spread of enteric infection among mice. Since then a series of reports have been published dealing with the investigation of particular problems along these lines (Topley, 1921 a and b, 1922 a and b, 1923, Topley and Wilson, 1923 a and b, Topley and Ayrton, 1924 a, b and c, Topley, Ayrton and Lewis, 1924 a and b, Topley, Wilson and Lewis, 1925).
On Proteus pseudovaleriae and its Occurrence in Man
Authors: de Assis A.
Published: May 2009

This paper deals with a micro-organism recovered from human blood in a case of a typhoid-like infection. No evidence could be produced of either typhoid or paratyphoid bacilli being the cause. Only one germ was recovered from blood cultures on two occasions, it was strongly agglutinated by the patient's serum, suggesting that it probably produced a true infection in man. This study was undertaken because certain features of the organism may lead to a faulty diagnosis of paratyphoid. The author deems it a new species in the light of the tests he applied and refers it to the genus Proteus Hauser (emend. Amer. Comm.) under the name Pr. pseudovaleriae.
The Production of Milk of Low Bacterial Content by means of Milking Machines
Authors: Mattick A. T. R. , Procter F.
Published: May 2009

This experiment has demonstrated that it is possible consistently to produce milk containing small numbers of bacteria and of good keeping quality by the use of milking machines.

It has been shown that the milking units and their rubber components may be successfully sterilised by steam.

The pipe lines have been shown to be a possible source of heavy contamination, and means of preventing this have been described.
A Serological Study of the Haemolytic Streptococci associated with Scarlatina
Authors: McLachlan D. G. S. , Mackie T. J.
Published: May 2009

1. A minority only of scarlatina streptococci are agglutinated by antisera for individual strains and no group agglutination has been observed.

2. Absorption tests reveal the existence of common or generalised agglutinogenic constituents but these are not restricted to scarlatina strains and can be recognised among the majority of the haemolytic streptococci isolated from various sources.

3. Though certain serological groups among scarlatina streptococci may be recognised as corresponding generally to “types” described by Smith and Griffith, there is such considerable antigenic overlap among the different groups that the differentiation and relationship of strains cannot be expressed satisfactorily by formulating definite serological types.

4. A system of serological analysis of scarlatina and other haemolytic streptococci is suggested (see Table IV).

5. While strains presenting particular serological characters may be associated more frequently with scarlatina, haemolytic streptococci with common serological characters occur both in scarlatina and other conditions. No essential serological distinction can be drawn between scarlatinal and other haemolytic streptococci and a “Streptococcus scarlatinae” group cannot be defined by serological methods.

6. Among the haemolytic streptococci derived from conditions other than scarlatina no relationship exists between serological characteristics and toxigenic properties (as evidenced by cutaneous reactions to culture nitrates).

We have to thank Drs J. Smith and F. Griffith for cultures of the type strains referred to in the text.