bluuebunny/crossref_metadata_2025 huggingface dataset:
Influenza complement-fixation. A simple quantitative micro-method
Authors: Belyavin G.
Published: May 2009

The complement-fixation technique described in this paper was designed as a simple and rapid micro-method. It is derived from the method published by Fulton & Dumbell (1949), but a number of modifications have rendered it less laborious to perform and more flexible in application. Using rabbit, human and guinea-pig antisera, this technique has been successfully applied to the serological examination of the viruses of influenza, vaccinia and Newcastle disease, and experience with other materials, such as gonococcal antigen and extracts of chorio-allantoic membrane and mouse lung, suggests that it is of general application.
Attempts to potentiate immunity to influenza in mice
Authors: Depoux R. , Mussett Marjorie V.
Published: May 2009

Under the conditions of our experiments, the local potentiation of immunity to influenza reported by FazekasdeSt Groth and Donnelley could not be demonstrated.

We should like to thank Dr C. H. Andrewes and Dr A. Isaacs for their advice and criticism, and Messrs E. Owen and D. Eade for their technical assistance.
The conglutination phenomenon: X. Conglutinin and immuno-conglutinin in guinea-pigs, pigs, donkeys, rats and mice
Authors: Coombs Anne M.
Published: May 2009

1. Immuno-conglutinin production by auto-stimulation was attempted in guinea-pigs, pigs, donkeys, rats and mice by the intravenous injection of a suspension of Gram-negative bacteria. The attempt was successful in rats and mice.

2. Experiments were carried out to elucidate the lack of response in guinea-pigs.

The author would like to thank Mr N. H. Hole of the Ministry of Agriculture Veterinary Laboratories at Weybridge, who inoculated and bled the donkeys used in these experiments.
Estimates of the infection rates for poliomyelitis virus in the years preceding the poliomyelitis epidemics of 1916 in New York and 1945 on Mauritius
Authors: Sample Donald W. , Evans C. A.
Published: May 2009

SUMMARY AND CONCLUSIONS

Data concerning numerous severe epidemics of poliomyelitis were surveyed for information useful in estimating the size of the immune component of the population by age groups of 1 year. The New York epidemic of 1916 and the Mauritius epidemic of 1945 were chosen as the most suitable for this purpose. It is shown that there was a regularly progressive decline in attack rates for successively older age groups from 2 to 8 years in New York. The attack rate in 8-year-olds was less than 10 % as large as that in 2-year-olds. It is noted that a difference of this magnitude could be accounted for by immunizing infections amounting to 30 % per year for 6 years.

A similar analysis of age specific attack rates during the Mauritius epidemic shows progressive declines of 28, 60, 50 and 53 % for the successive age groups 5–9. An average annual infection rate of 45 % over a 4 year period could account for the ten-fold difference in infection rates between 5-year-olds and 9-year-olds.

An immunizing infection rate of 30 % a year would lead to a pattern of immunity in which the seven youngest age groups had a total susceptible component of 30 % at the beginning of a ‘ poliomyelitis season’. Twenty per cent would remain susceptible at the end of the season when spread of virus terminated.

An annual immunizing infection rate of 45 % would bring about a situation in which 21 % of the five youngest age groups were susceptible at the start of a period of viral prevalence and 12 % at the end. Alternatively, one could consider that on Mauritius there may have been a continuous prevalence of virus in a population in which approximately 15 % of the five youngest age groups were susceptible at any time.

It is suggested that the essentially similar attack rates among children 3–5 years old on Mauritius may have reflected a 3-year period during which homotypic virus was not prevalent, in contrast to its great prevalence during the years prior to that time.

A more detailed discussion and analysis of additional data concerning age-specific attack rates in poliomyelitis will be found in the thesis submitted by Dr Sample to the University of Washington School of Medicine entitled, ‘Some observations on statistical and theoretical epidemiology of infectious diseases, principally poliomyelitis’, in 1955. This is obtainable by Inter-library Loan from the Health Sciences Library, University of Washington, Seattle.

We wish to express our sincere thanks to Dr Blair M. Bennett and Dr William E. Reynolds of the University of Washington for their advice on the statistical and epidemiologic aspects of this study.
Properdin and the defence of burns against infection
Authors: Lowbury E. J. L. , Ricketts C. R. , Hall M. , Hurst L. , Lilly H. A.
Published: May 2009

Treatment of serum with the insoluble polysaccharide residue of yeast cells (zymosan) has been shown (a) to decrease the bactericidal power of serum for certain bacteria; (b) to remove from some sera a factor essential to the interaction of zymosan with the third component of complement. The adsorbed protein (properdin) was eluted from zymosan and found to contain α2, β and some γ globulins. It was shown to restore partially the normal characteristics to treated serum (RP).

Properdin levels have been estimated in the sera of eighteen burned patients and in twelve normal subjects. There was evidence of a reduced level in the patients' sera. The limitations of the assay method are discussed.

Bactericidal activity of normal serum containing properdin was tested against nineteen Gram-negative bacilli isolated from burns.Ps. pyocyanea, Proteus and Klebsiella, which are commonly found in burns, were with one exception resistant or slightly sensitive to the bactericidal action of this serum.Bact. coli, which is uncommon in burns, was usually highly sensitive.

From our preliminary studies reported here it would seem that the properdin system cannot be expected to kill the flora in established infections of burns, and properdin is therefore unlikely to prove useful as a therapeutic agent. However, it probably has an important role as one of the defence mechanisms of uninfected tissues.

We wish to thank Dr Derrick Rowley and Dr A. C. Wardlaw for helpful discussions, and Dr W. Weiner for his advice and co-operation. We are grateful to Miss Stella Baar, F.R.I.C., for N and P analyses.
Staphylococcus aureus in the infant upper respiratory tract: II. Observations on domiciliary-delivered babies
Authors: Hurst Valerie
Published: May 2009

Of thirty-six babies delivered at home 72% acquired Staph. aureus in their noses and throats within their first fortnight of life. The carrier rate among the twenty-eight who were subsequently followed was 65% during the first fortnight period. Only 18% acquired penicillin-resistant strains, in contrast to the previously observed hospital-born group, 97% of whom acquired strains resistant to penicillin. Phage typing demonstrated that the home-born babies who acquired Staph. aureus during their first fortnight carried the same strains throughout the 15–25 week observation period. As in the hospital-born babies, many of them tended to lose the strains from the nose while retaining them in the throat. Strains having phage patterns of Groups I and II were most common among the home-delivered babies, whereas among the hospital-born babies Groups I, III, or untypable strains were most frequent. There was no evidence that the penicillin sensitive strains acquired from the home are carried for shorter periods than the penicillin-resistant strains of the hospital. Babies failing to acquire Staph. aureus within the first fortnight tended either to acquire it in the throat alone, or to remain non-carriers. It is suggested that babies who do not become carriers within the first two months of life are unlikely to do so later.

I owe thanks to many people: to the late Prof. Sir Alexander Fleming for generously extending the laboratory facilities of The Wright-Fleming Institute; to Prof. Robert Cruickshank for patient guidance and invaluable suggestions; to Dr R. E. O. Williams for providing materials and laboratory space for the phage typing, and to Dr Joan E. Rippon for instruction in the phage typing technique; to Dr Agnes H. W. Smythe for the co-operation of the Marylebone and Lisson Grove Child Welfare Centres, and to Mrs Eastham and Miss MacGilley who took the swabs there; to Dr W. Howard Hughes, Dr W. G. Booth, and Dr K. Hart for arranging co-operation of the Ealing Public Health Department; to the Ealing midwives who collected the swabs from the domiciliary-delivered babies; to members of the Wright-Fleming Institute technical staff.

Also, I am grateful to the following organizations for personal grants while conducting the study: The United States Educational Commission in the United Kingdom for a Fulbright Scholarship, 1951–53; The University of California for a grant from the Student Aid Fund; Sigma Delta Epsilon for a Fellowship Award.
Adaptation of Mahoney, Type I, poliomyelitis virus to suckling mice
Authors: selzer Golda
Published: May 2009

The Mahoney, Type I, poliomyelitis virus undergoes two ‘cycles’ of multiplication in the CNS of suckling mice—the first within 48 hr. after intracerebral inoculation, and the second approximately 10 days later. The former may not be associated with paralysis whilst the latter usually is.

By to-and-fro passage in suckling mouse brain and monkey kidney-tissue culture there is a gradual increase in the amount of virus obtained during the early multiplication cycle in suckling mouse brains and associated with this is the occurrence of early paralysis in 80% or more of these mice. The virus capable of causing early paralysis in infant mice is gradually lost by direct mouse-to-mouse passage.

The occurrence of two variants is postulated, one of these apparently nonparalytic and multiplying selectively in suckling brains.

The author would like to thank the late Prof. M. van den Ende for his stimulating discussions and advice, Dr P. K. Olitsky of New York for his constant interest, and Mr T. C. Norcott for his able technical assistance.
The incidence of infection with poliovirus and other viruses in cases of aseptic meningitis (‘nonparalytic poliomyelitis’) in Sheffield in 1954
Authors: Tyrrell D. A. J. , Balducci D. , Snell B. , Zaiman T. Elisabeth
Published: May 2009

1. Sixteen cases of paralytic poliomyelitis and twenty-four cases of aseptic meningitis (‘non-paralytic poliomyelitis’) occurring in the Sheffield area were studied clinically and by virological methods.

2. Poliovirus was isolated from thirteen of the sixteen cases of paralytic poliomyelitis and from three of the twenty-four cases of aseptic meningitis. In another two of the cases of paralytic poliomyelitis and another six of the cases of aseptic meningitis serological evidence of poliovirus infection was obtained.

3. Serological evidence of Coxsackie virus infection was found in four of the cases of aseptic meningitis; but in one there was also clear-cut evidence of poliovirus Type 3 infection, and in another it seemed that the infection was contracted in hospital. Evidence of Coxsackie virus infection was also obtained in five cases of paralytic poliomyelitis.

4. Serological evidence of Adenovirus infection was found in one case of aseptic meningitis.

5. No acceptable evidence was found of infection with Columbia SK or related viruses, or with the virus of lymphocytic choriomeningitis.

6. From one patient with aseptic meningitis an unidentified virus was isolated.

We wish to thank Dr J. Kennedy for permission to study patients and Prof. C. P. Beattie and Prof. C. H. Stuart-Harris for help in preparing the manuscript.
Aseptic meningitis due to infection with ECHO virus (Type 9)
Authors: McLean D. M. , Cameron D.
Published: May 2009

Eleven cases of aseptic meningitis occurred in a Cambridgeshire village between 17 October and 11 November 1955. The syndrome consisted of severe headache, backache, vomiting, fever and neck stiffness together with lymphocytes and frequently some granulocytes in the cerebrospinal fluid. Principally, it affected persons aged between 10 and 30 years. Out of a total population twenty-three at risk, seventeen were infected and eight became ill. A further three contacts who were living in Cambridge became ill.

Identical strains of virus were isolated from the faeces of two patients by inoculation of trypsin-dispersed human amnion cells and from the faeces of another two patients by inoculation of monkey kidney cultures. Bourn virus, which belonged to the ECHO group, Type 9, multiplied readily and produced cytopathogenic effects in human amnion and monkey kidney cultures, but it was not cytopathogenic in HeLa cell cultures. These investigations strongly suggest that Bourn virus caused the epidemic.

We wish to thank Dr M. G. P. Stoker for his advice and criticism and Mrs B. M. Cook for technical assistance.

We are indebted to Dr J. O'H. Tobin and Dr F. K. Sanders for advice on certain technical procedures.

It is a pleasure to acknowledge the assistance given by many colleagues and friends, including Dr D. I. Annear, Miss D. K. Bell, Mrs D. Ditchburn, Dr R. M. Fry, Dr D. Gairdner, Dr J. E. Power, Dr D. Simpson, Dr P. Tyzer and Dr P. J. Wormald.
Aseptic meningitis caused by ECHO virus
Authors: Lahelle O.
Published: May 2009

1. An investigation of ninety-eight cases of aseptic meningitis admitted to hospital resulted in the isolation of ECHO virus Type 6 from fifty-one patients.

2. The viruses were cultivated in both human embryonic skin-muscle tissue and human amniotic cell tissue. The latter was found to be more satisfactory.

3. Forty-eight strains were isolated from the stools of patients, six from the cerebrospinal fluid and four from throat-washings.

4. Serological examination of patients from whom the virus was isolated showed that a significant proportion of patients exhibited a specific antibody response. This included three out of six patients with the virus in their cerebrospinal fluid.

5. The clinical picture of aseptic meningitis from which cases ECHO virus was isolated cannot be distinguished from that caused by other known viruses.

6. The evidence presented supports the claim that ECHO virus Type 6 is one of the causes of aseptic meningitis.

Grateful appreciation is acknowledged to Prof. P. M. Holst (Oslo), Prof. Johs. Böe (Bergen), Dr B. Helland-Hanssen (Molde), Dr O. Römcke (Drammen), Dr R. Tingstad (Namsos), and Dr A. H. Brinchmann (Bærum), for providing specimens and case records. I am also grateful to Mrs B. Zapffe and Mrs L. Kohmann for expert technical assistance.
The titration of vaccinia virus by the pock counting technique
Authors: Kaplan C. , Belyavin G.
Published: May 2009

Ninety-seven groups of five-membrane pock counts from 115 titrations of vaccinia virus preparations were examined in an attempt to identify the statistical distribution followed by such counts, and to obtain an estimate of the overall coefficient of variation of the technique.

It was found that the distribution of counts was neither Poissonian nor normal, and that the count variances ‘wandered’ so extensively that no valid estimate of the overall coefficient of variation was possible. Nor was it possible to assess the intrinsic reproducibility of the test, although it is empirically a useful one.
Protection of mice by living Vi and O vaccines against death caused bySalmonella paratyphi C
Authors: Archer G. T. L. , Whitby J. L.
Published: May 2009

In seeking a more satisfactory test than the conventional mouse-protection tests for the assessment of typhoid-paratyphoid vaccines in relation to their O and Vi antigens, it was decided to undertake a series of experiments with vaccines containing the somatic antigens ofSalmonella paratyphi Cand to use this organism to challenge mice thus immunized.Salm. paratyphi Ccontains the same Vi antigen asSalm. typhiand moreover it is capable of giving rise to a true infection in mice in contrast to the acute intoxication which follows a fatal dose ofSalm. typhi.

Large doses, of the order of 100 × 106, of this paratyphoid organism injected intraperitoneally into mice resulted in acute intoxication with death in 24–72 hr., similar in every way to the picture with typhoid bacilli, but when the dose was reduced 100-fold or more an infective illness was set up which after an interval of 5–10 days or more, during which the organisms multiply freely in the tissues, terminated fatally. Typhoid bacilli do not produce a true infection in mice.

Living vaccines were prepared ofSalm. typhiTy6S (an almost pure Vi strain) andSalm. cholerae-suis(contains the same O-antigen complex asSalm.paratyphi C). These were used separately, and in combination, to immunize different batches of mice by the subcutaneous route against a subsequent intraperitoneal challenge with a Vi-positive culture ofSalm. paratyphi Cat both high- and low-dose levels. The different challenge doses were to assess the relative values of the 0 and Vi components in protecting against intoxication (high dose) and infection (low dose), respectively.

Against intoxication pure Vi vaccines were almost as effective as Vi + O vaccines, whereas pure O vaccines gave little or no protection.

Against fatal infection the combined Vi + O vaccine offered good protection and the pure O vaccine was but little inferior, whereas the pure Vi vaccine appeared to be without significant effect.

Quite small doses ofSalm. paratyphi Cadministered by the intra-gastric route can give rise to a general infection in mice, but in order to obtain consistent results much larger doses were found necessary (about 300 x 106organisms). Mice immunized with the same three vaccines and subsequently challenged by the intragastric route with this large dose showed significant protection throughout. The combined, O + Vi, vaccine did not appear to have any advantage over the pure O vaccine, but both were markedly superior to the pure Vi vaccine. Further experiments on the same lines are however necessary to see if the results obtained in this single experiment are reproducible.

The relationship of the above findings to the evaluation of agents employed in man for the prophylaxis of enteric fever and the need for further experimental work of a similar nature are discussed.

We wish to thank Dr F. Kauffmann for strains ofSalm. paratyphi C, Lt-Col. T. E. Field, whose results we have freely quoted, and Dr S. Peto for advice on statistical evaluation of our results.
Studies in the variability of pock counts
Authors: Armitage P.
Published: May 2009

1. The relationship has been examined between the variance and the mean of pock counts made by a number of different workers.

2. In all cases the variance was considerably greater than that expected if the distributions were of the Poisson form. Recent work of Westwoodet al.(1957) suggests that variation approaching the Poisson expectation can be achieved by appropriate technical measures.

3. With one exception, there appeared to be a linear relationship between the logarithm of the variance and the logarithm of the mean. The slope of this line varied from one laboratory to another, but not, apparently, from one occasion to another in any one laboratory.

4. The hypothesis that for any set of egg membranes the expectations of the pock counts bear constant ratios to each other, irrespective of the virus density, was untenable: the observed variances increase less rapidly with high counts than would have been expected on this theory.

5. Statistical methods are proposed for comparing and combining sets of counts at different dilutions. If Poisson variability were achieved, simpler methods would be available.

I am much indebted to Dr L. Collier, Prof. A. W. Downie, Dr C. Kaplan and Dr F. O. McCallum for permission to use their unpublished data; to Dr J. C. N. Westwood for discussing with me his (then) unpublished work; to Miss Irene Allen for computing assistance; and to Mrs G. M. Young for the preparation of the diagrams.
Streptococcal infections among children in a residential home: II. Potential sources of infection for individuals
Authors: Holmes Margaret C. , Williams R. E. O. , Bloom C. V. , Hirch Ann , Lermit Ann , Woods Eileen
Published: May 2009

1. For each case of streptococcal illness—sore throat, otitis, or other respiratory tract illness—observed in a 30-month study in a large children's home an attempt was made to enumerate the infected contacts from whom the infection might have been derived.

2. Of 459 illnesses, 10·5% seemed to be relapses of a previous illness, and in 10·0% the child was known to have been carrying streptococci for more than 7 days before sickening, so that the causal relation of the streptococcus is in doubt.

3. Of the 365 other illnesses, 31·5% could be attributed with varying degrees of confidence to infection from one specified carrier, 36·8% could have been derived from one or more recognized contacts although there was not sufficient evidence to specify one in particular. For 17·5% no infected contacts were recognized, but infection with the particular streptococcus was known to be present in the community; and for 9·3% there were no contacts and the streptococcus was not known to be present in the Village.

4. Of the ninety-four illnesses for which the source could be specified as one particular carrier, 66% were derived from heavy nasal, 19% from light nasal, and 15% from throat carriers. Persons incubating a streptococcal illness and healthy carriers were each responsible for 31% of the illnesses and convalescent carriers for 38%.

5. It seemed that at least 50% of all illnesses could have been contracted from contacts within the cottage; the proportion due to school infection was much more difficult to estimate but was at least 12%.
Determination of bacterial air pollution in various premises
Authors: Cvjetanović B.
Published: May 2009

A simple method, applicable in routine work, for simultaneous air sampling of total bacteria, on serum agar, and Str. salivarius and Bact. coli on specific media, is described.

Simultaneous air sampling including, in addition to detection of total bacteria, Str. salivarius and Bact. coli as indicators of buccal and faecal air-borne bacteria, respectively, reveals the kind and source of air-borne pollution much better than the simple total bacterial count.

The air in various medical and public institutions was examined; the results are presented and discussed. The air pollution of the premises examined was relatively high, especially in the operating theatres. The air of infants' wards was found to be heavily polluted with Bact. coli as a result of poor nursing technique and this might have had bearing on the epidemic of infant diarrhoea.
Ringtail in new-born Norway rats. A study of the effect of environmental temperature and humidity on incidence
Authors: Totton Michael
Published: May 2009

Ringtail in infant rats is shown to depend on humidity over a wide temperature range. It is not due to infection or diet, but probably to chronic cooling by evaporation, convection and conduction.

Rats should either be bred in cages with solid floors, or else be given environmental conditions resembling those in the natural nest, which keep the young at a low saturation deficit during the early post-natal period.

I am glad to express my thanks to M. Potter, Senior Animal Technician, for his invaluable aid in keeping the records of the experimental programmes, and to G. Dimmock for his help in building and maintaining apparatus. I am also grateful to the University of London for the loan of a Cambridge portable potentiometer.
Comparison of the infectivity of influenza Viruses in two host Systems: the Allantois of infect Eggs and Surviving Allantois-on-Shell
Authors: Groth S. Fazekas de St , White D. O.
Published: May 2009

It is shown that the assay for infectivity in bits of allantois-on-shell, which has been standardized on the BEL strain, is optimal also for nine representative strains of influenza virus tested.

On the average, the sensitivity of the technique is the same as of orthodox allantoic infectivity tests; its precision is always higher. The relative sensitivity of the two tests varies from strain to strain, the log tray/egg differences being SW (+0.88), MEL (+0.51), CAM (+0.31), PR8 (0.28), WSE (+0.25), HUT (−0.02), BEL (−0.22), FMI (−0.35), LEE (−0.47), BON (−1.02). This gradient is the same for fully infective and incomplete forms of influenza virus.

The tray/egg gradient of susceptibility is negatively correlated with the variation in host resistance.

The differences in susceptibility are not due to any effect of the plastic trays, to thermal inactivation of the virus, to differences in adsorption or viropexis in the two test systems or to the effect of allantoic fluid on the virus particle. The critical step has been shown to occur during the intracellular stage of multiplication.
The detection of cholera vibrios in Calcutta waters: the River Hooghly and canals
Authors: Abou-Gareeb A. H.
Published: May 2009

1. Before undertaking a bacteriological survey of the waters of the Hooghly River and the associated canals a detailed epidemiological study over the past 20 years of cholera, as it affected the individual administrative wards of Calcutta, was undertaken. Sampling points were selected in accordance with the results of this study. Samples of water from the various points were collected at intervals extending from December 1958 to August 1959 in 2½–5 l. amounts. The whole sample in each case was filtered through special filter pads. The pads were first cultured in an enrichment medium from which plate cultures were subsequently made for colony isolation, serological and biochemical examination.

2. The sampling points on the canals were all adjacent to areas where the local endemicity was judged to be high; other points were by bathing ghats, etc. A total of eighty-nine samples covering all the sampling points were examined and Vibrio cholerae were isolated from twelve of these samples, eight of which came from twenty-six samples collected from two sampling points on the Chetla and Circular Canals, respectively.

3. The positive isolations were spread fairly evenly over the whole period of the study which covered both epidemic and non-epidemic periods including the monsoon. Although the incidence of cholera in Calcutta may fall to a low level during non-epidemic periods cases continue to occur throughout the year and the relationship of the maintenance of the infection in the city to the continuous potential infectivity of the open natural waters of Calcutta is discussed.
Heat labile and heat stable factors and antibodies in normal and immune sera against T-system bacteriophages
Authors: Çetin Enver Tall
Published: May 2009

1. Heat labile and heat stable inactivating factors against T-system phages are present in normal guinea-pig and rabbit sera. These may be antibodies.

2. Sera of guinea-pigs immunized with phages T2, T3and T4contain heat labile and heat stable antibodies.

3. The heat labile activity is absorbed from guinea-pig serum by phage more readily than the heat stable activity.

4. Dilution of the sera reduces the heat labile activity more than the heat stable activity.

5. Complement has no effect on the inactivation or neutralization of phages T2, T3and T4by normal or immune guinea-pig sera.
Some properties of fluoracetamide as a rodenticide
Authors: Bentley E. W. , Greaves J. H.
Published: May 2009

1. The average lethal dose of fluoracetamide for wild R. norvegicus was found to be 13 mg./kg. of body weight and the LD95, about 43 mg./kg.

2. Wild rats offered bait contatining 0·5, 1 and 2% fluoracetamide, after a period of conditioning, seemed to find it palatable and, on the average, ingested the equivalent of 18–100 LD50's. Warning symptoms appeared in about an hour or longer and included short convulsive spasms.

3. The speed of onset of warning symptoms leading to cessation of feeding was studied in albino rats dosed with the equivalent of 2 LD50's of sodium fluoracetate, zinc phosphide or fluoracetamide. Feeding ceased soonest in the case of sodium fluroacetate. Zinc phosphide gave very variable results, but it is thought that if wild rats had been used, feeding would have stopped nearly as soon as with sodium fluoracetate.

4. It is considered that field trials to compare the efficiency of 1% flouracetamide and 2·5% zinc phosphide, both with ‘prebaiting’, would be well justified.

5. Fluoracetamide at 2% may also prove to be a good alternative to 0·25% sodium fluoracetate as a ‘direct’ poison for controlling rats in sewers.

We are indebted to Miss Y. Larthe and Miss E. J. Taylor who took part in the bioassay and in one of the experiments with the marked rats.
Observations on leptospiral antibodies occurring in pig sera
Authors: Davies M. Elizabeth
Published: May 2009

A total of 849 samples of pig sera were tested for antibodies to L. canicola, L. icterohaemorrhagiae, L. pomona, L. ballum, L. sejroe, L. grippotyphosa, L. hyos (mitis Johnson), and L. bataviae. Positive results were obtained in 57 samples to all but the last three serotypes.

I wish to thank Mr J. Norval of Edinburgh and Mr W. R. P. Hildebrand of Belfast for supplying the sera and Dr A. Wilson Taylor for his interest and supervision.

I am greatly indebted to the late Dr J. C. Broom of the Wellcome Laboratories of Tropical Medicine for the supply of leptospira.
Heredity, infection and chemoprophylaxis in rheumatic carditis: an epidemiological study of a communal settlement
Authors: Davies A. Michael , Lazarov Eliahu
Published: May 2009

1. Children and their parents in a communal settlement (kibbutz) were followed for 14 months with special regard to the influences of streptococcal carrier rate, streptococcal infections, chemotherapy and heredity on the pattern of rheumatic heart disease.

2. Children with proven or probable heart disease showed the same streptococcal carrier rates as controls in spite of continued chemoprophylaxis with oral penicillin.

3. A single injection of penicillin, given to all kibbutz members on the same occasion, reduced the streptococcal carrier and infection rates to zero and maintained a marked drop for 3 months. Thereafter, the rates rose to higher levels than before. Courses of sulphamethoxypyridazine (‘Lederkyn’) given first to the total population and then to children only, caused only temporary interruption in the attack rate.

4. The prevalence of rheumatic heart disease in children of parents themselves affected was 2½ times greater than in controls exposed to the same environmental risks.

5. Affected children were more susceptible to streptococcal infections than controls with identical exposure.

Grateful thanks are due to Miss Pearl Weiskopf, B.Sc., for the statistical analysis. Without the close collaboration of Dr J. Yauluss, Nurses Tova and Ziva and the members of Kibbutz S this study would have been impossible. Thanks are also due to Lederle Laboratories Department of Cynamid International and their Israeli agent, Dr L. Goldshmidt, for the gift of ‘Lederkyn’, and to Mrs Rachel Kosh for help beyond the call of her secretarial duties.
Detection of bacterial antigens by means of sensitized guinea-pig ileum
Authors: Buckland F. E.
Published: May 2009

Using a Dale organ bath and the ileum of passively sensitized guinea-pigs a specific sensitive reaction with as little as 1 μg./ml. of disintegrated whole cultures of various bacteria and 0·01 μg./ml. of purifiedSh. dysenteriaeandS. typhimuriumpolysaccharides was obtained.

More detailed study showed that 1 μg./ml. ofSh. dysenteriaedegraded polysaccharide derived from the O antigen could be detected with consistency. Lower concentrations gave irregular results.

My thanks are due to the David Bruce Laboratory for supplying the antisera and the bacterial suspensions, to Prof. W. T. J. Morgan of the Lister Institute of Preventive Medicine for the antibody nitrogen determinations, to Dr D. A. L. Davies of the Microbiological Research Establishment, Porton, for the antigen preparations and to Corporals G. Willis and P. Brown, R.A.F., for much careful work in day to day experiments.
The growth and death of wound bacteria in serum, exudate and slough
Authors: Colebrook Leonard , Lowbury E. J. L. , Hurst L.
Published: May 2009

Six strains of Str. pyogenes and four strains of Staph. aureus were found to grow well from large or small inocula in fresh human serum; four strains of E. coli failed to grow from large inocula and were killed when the inocula were small. Ps. pyocyanea, Proteus and Str. viridans sometimes grew and sometimes failed to grow in fresh serum.

In serum which had been treated with trypsin or heated at 56° C. for 1 hr. the Gram-negative bacilli grew readily, and growth was still better in serum which had been heated and then trypsinized. Heating at 56° C. and treatment with proteolytic enzymes were shown to destroy complement and to inactivate the bactericidal activity of fresh serum against a Shigella highly sensitive to the properdin system. It is suggested that these changes might be enough to explain the conversion of serum by proteolytic enzymes into a suitable medium for the growth of coliform bacilli. This change might be brought about by bacterial or leucocytic enzymes. Fibrinolytic serum from a cadaver was found to retain at least a part of its complement and bactericidal activity.

Strains of E. coli, Ps. pyocyanea, Proteus, Staph. aureus and Str. pyogenes were tested for growth in burn slough suspension and blister fluid. In slough suspension all strains grew well, but the Gram-negative bacilli grew rather more vigorously than the Gram-positive cocci. In blister fluid E. coli was killed and other strains grew.

These findings are discussed in relation to wound sepsis.
Zone electrophoresis of poliovirus partially inactivated by formaldehyde
Authors: Polson A. , Hampton J. W. F. , Deeks D.
Published: May 2009

It was shown in this work that the electrophoretic mobility of the MEF1 strain of poliovirus was increased approximately 25% after interrupted inactivation with formaldehyde. This is in accordance with past observations on the behaviour of formaldehyde-treated proteins. The residual live virus had the same mobility as the ‘killed’ virus, thus indicating that the surfaces of all the virus particles have been affected to the same degree by the inactivating agent.

Gel precipitin tests performed on the different samples obtained by zone electro-phoresis showed, in addition to the main antigen, the presence of a small amount of a second component of slightly higher mobility, and, as it occurs in the main fraction and the sample thereafter it probably has a slightly higher mobility than the main component.

The antigenic properties of the different fractions as shown by the production of antibodies in guinea-pigs correspond with the presence of precipitating antigen in the samples in the region of highest antigen concentration. The faint antigenicities of the fractions obtained from the regions higher up in the zone electrophoresis column are due to small amounts of virus antigen similar to that found in the column on electrophoresis of untreated MEF1 virus, bearing in mind that the inactivated virus was concentrated approximately 2000 times for zone electrophoresis.
The sterilization of surgical rubber gloves and plastic tubing by means of ionizing radiation
Authors: Oliver R. , Tomlinson A. H.
Published: May 2009

Threads were infected with the spores of four species of bacteria and put inside rubber gloves which were sealed into plastic bags and irradiated with electrons or gamma rays. A dose of 1·5 Mrad. killed approximately 99·99% of the spores of each species and a dose of 2·5 Mrad. appeared to give an adequate margin of safety for sterilization. Spores were similarly killed inside plastic tubing and within the lumen of hypodermic needles.

The tensile strength of the gloves decreased with increasing doses of radiation so that the rough, solution-dipped gloves tested were significantly weaker after 8·0 Mrad., but the smooth gloves tested still complied with the British Standard after 30 Mrad. When vacuum-packed before irradiation, rough gloves were still satisfactory after 16 Mrad., and smooth gloves were apparently unaffected by 30 Mrad.; they could, therefore, be sterilized six and twelve times, respectively.

Radiation gives dependable sterilization of rubber gloves, and the use of a sealed plastic package obviates subsequent contamination. The possibility of using disposable radiation-sterilized gloves is discussed, the use of a plastic radiation indicator suggested and the practical applications of radiation sterilization in the hospital considered.
Brucellosis in dairy herds—some applications of the milk ring test
Authors: Ferguson G. S. , Robertson A.
Published: May 2009

1. It has been shown that cows infected with brucellosis of the udder can usually be detected by an application of a modified milk ring test, based on the finding that milks from infected cows, in addition to showing a high bulk MRT titre also show considerable quarter variations. The effects of adult vaccination with strain 19 vaccine on the MRT are reported; low bulk titres with uniformity between quarters, except at the beginning and end of lactation and immediately following vaccinations, were observed, thus making differentiation between vaccinated and infected cows possible.

2. In a survey of raw milk samples from three areas in southern Scotland, 3·5, 5·3 and 9·0% of samples were shown to be infected with Br. abortus.
Studies in the epidemiology of infectious myxomatosis of rabbits: VII. The virulence of strains of myxoma virus recovered from Australian wild rabbits between 1951 and 1959
Authors: Marshall I. D. , Fenner Frank
Published: May 2009

During the 8½ years, February 1951 to July 1959, 672 strains of myxoma virus were recovered from the field in Australia, all but thirteen, which were derived from mosquito pools, being extracted from the tissues of infected wild rabbits. These were tested for virulence by the intradermal inoculation of small groups of rabbits with a small dose of virus. Based primarily on survival times, strains have been allocated to five grades of virulence, ranging from very high to very low. In spite of inadequate sampling during the first 5 years there has clearly been a trend from a predominance of highly virulent strains in the initial epizootics to a mixture of strains of virulence varying from very high (rarely) to very low. For the last 6 years the proportion of strains allotted to the different virulence grades has remained almost constant, just over half the strains tested each year being classified as moderately virulent.
A comparison of plague vaccines by the mouse protection test
Authors: Bucklakd F. E. , Treadwell R. H.
Published: May 2009

1. In our hands the assay of a plague vaccine, in terms of its power to protect mice against what was hoped to be a standard challenge, was found to be impracticable.

2. Assay by mouse protection tests in terms of a Standard vaccine was found to be possible, but it proved to be a very time-consuming procedure and demanded the use of an almost prohibitively large number of mice for a sufficient number of replicate tests which are required to offset the variability in the method. Theoretically a single test might be adequate if the numbers of immunized mice were very large, but there are obvious limitations to the numbers of mice that can be included in a single test of this nature.

3. The Ouchterlony plate technique proved to be useful in indicating the antigens present in a particular vaccine, but not on a strictly quantitative basis.

4. The vaccine prepared from the virulent human strain ofP. pestiswas found to protect mice more efficiently than those prepared from avirulent strains and when the protective potency was expressed in terms of content of antigen and high molecular weight substances the vaccine prepared from the virulent culture was found to be even more potent than the Standard acetone-dried vaccine.

5. The use of formalin as a preservative results in some loss of potency of a vaccine but, provided the strain ofP. pestisused for the preparation of the vaccine is highly virulent, this need not be serious and is offset by a number of advantages.
The intranasal infection of mice with Bordetella pertussis
Authors: Dolby Jean M. , Thow Doraine C. W. , Standfast A. F. B.
Published: May 2009

Bordetella pertussis instified by the intranasal route into the lungs of mice multiply without difficulty even from small inocula, although B. pertussis is not a natural pathogen for mice and mouse to mouse infection could not be demonstrated. When the initial dose was large the bacilli multiplied until the number in the lungs reached a critical level at which the mouse died. With smaller doses the critical level was never reached; a maximum count was achieved in 10–14 days, after which the number of viable bacilli declined. These smaller doses were consistently non-lethal and the figures for the viable counts when plotted gave curves of typical shape which were called ‘sublethal curves’. The decline corresponded in time with the development of specific immunity. Growth in the lung during the first 4 days of the infection was exponential, the rate of increase in the viable count depending on the size of the inoculum; the smaller the inoculum the faster the increase. With infecting doses at about the critical level, the numbers did not increase during the first 3–4 days, and with larger doses they decreased during the first 2–4 days of infection.

Antiserum given with the inoculum reduced the number of viable organisms in the lung at once. Its effect was short-lived, because after 24 hr. the lung count rose; nevertheless, the initial check on the bacteria had converted a lethal in fection into a sublethal infection.
Antigens common to Types 1 and 2 poliomyelitis viruses
Authors: Selzer Golda , Larsson K.
Published: May 2009

During a recent epidemic of poliomyelitis three viruses isolated (one Type 1 and two Type 2) elicited both Type 1 and Type 2 CF and precipitating antibodies in the patients whilst only the homotypic neutralizing antibodies were present. These viruses inoculated into animals produced specific CF and neutralizing antibodies, but precipitating antibodies to both types were present in a significant number of animals. These findings suggest that certain polioviruses have complement-fixing and precipitating antigens common to both Type 1 and Type 2 viruses.

We would like to thank our colleagues in the Virus Research Unit for their helpful advice and criticism and Dr J. Hampton (Poliomyelitis Inst., Johannesburg) for the concentrated Type 1 poliovirus vaccine.
A note on the immunogenicity of ultra-violet irradiated vaccinia virus in man
Authors: Kaplan C. , McClean D. , Vallet L.
Published: May 2009

A preparation of vaccinia virus inactivated by ultra-violet irradiation under strictly controlled conditions, and shown to produce neutralizing antibody and resistance to challenge in rabbits, was active in only about half of 37 human volunteers. It was not, therefore, likely to be usefully immunogenic in man. In the largest single test, 15 of 25 men had unmodified primary skin reactions when challenged with living virus, although five of these had circulating antibody. On the other hand, only three of 10 men who responded to challenge with modified or negative reactions, had no circulating antibody.

In man the presence of circulating antibody does not necessarily indicate resistance to infection in the skin, nor does skin immunity always indicate the presence of circulating antibody.
The pasteurization of liquid whole egg and the evaluation of the baking properties of frozen whole egg
Authors: Heller C. L. , Roberts B. C. , Amos A. J. , Smith Muriel E. , Hobbs Betty C.
Published: May 2009

Experiments carried out by the British Egg Marketing Board in order to establish a heat treatment which would effectively pasteurize liquid whole egg are described.

The results of large scale bakery trials and subsequent trade demands indicate that the recommended pasteurization treatment gives a product of a satisfactory baking performance.

It is recommended that for the adequate pasteurization of whole-egg products, a temperature of 64·4°C. (148° F.) for the minimum holding time of 2·5 min. should be used.
Zone electrophoresis of enteroviruses
Authors: Polson A. , Deeks D.
Published: May 2009

Zone electrophoresis in a sugar concentration gradient is proposed as a complementary method for the biological classification of the enteroviruses. Under standardized experimental conditions it was found that the majority of the Coxsackie A viruses and the polioviruses have a common, low electrophoretic mobility. sackie A viruses and the polioviruses have a common, low electrophoretic mobility. The impression was gained that the ECHO viruses show the highest electrophoretic mobility, though in some cases there is overlapping with the Coxsackie Bs. The mobility of both of these groups is considerably higher than that of the other two.

Zone electrophoresis appears to be an excellent method for the purification of the enteroviruses prior to the production of specific precipitating antibodies.
The measurement of bacterial respiration on pig skin with micro-respirometers
Authors: Woodroffe R. C. S.
Published: May 2009

1. The respiration of bacteria normally present in thin slices of skin taken from pig's trotters has been measured in Cruickshank micro-respirometers.

2. These respirometers were originally designed to measure skin respiration in a medium including antibiotic to inhibit bacterial activity. The skin and medium was contained in a glass well. Using pig skin in a similar system without antibiotic, bacteria left the skin to grow independently in the medium. To overcome this difficulty polythene cups were made with an inner compartment for the tissue without medium and an outer compartment for water which provided a humid atmosphere.

3. Using polythene cups without medium the skin respiration was neglible, bacterial respiration was measured in situ and correlation between oxygen uptake and bacterial counts was obtained. This correlation was valid within experiments only.

4. Respiration of skin samples taken from adjacent areas of pig's trotter was similar, but there was large variation between samples from different trotters.

5. Respiration due to bacteria increased rapidly for 6–9 hr., followed by a slower increase. This may be due to a limited food supply or to a state of equilibrium.
A respirometer technique for estimating germicidal activity on skin
Authors: Woodroffe R. C. S.
Published: May 2009

1. A technique for measuring the antibacterial activity of germicides on pig skin in micro-respirometers has been described.

2. Using this technique the activity of the following germicides has been estimated: 2,2-dihydroxy, 3,5,6,3′,5′,6′-hexachlorodiphenylmethane, 3,4,4′-trichlorocarbanilide, 3,5,4′tribromosalicylanilide, 2,2′-thiobis (4,6-dichlorophenol), Irgasan CF3*, 3,5,3′,4′-tetrachlorosalicylanilide.

3. The results obtained have been discussed in relation to hand-washing test results (Hurstet al.1960).
Observations on antigenic variation in a strain ofTrypanosoma bruceigrowing in mice
Authors: Watkins J. F
Published: May 2009

Variation in agglutinating and protective antigens was studied in a strain ofTrypanosoma bruceigrowing in mice protected with anti-trypanosomal rabbit serum. It was concluded that the agglutinating and protective antigens were the same, and that variation in the antigenic structure of trypanosome populations exposed to antiserum was due to mutation and selection rather than to adaptation. The mutation rate per organism per division cycle required to account for the experimental findings on the mutational hypothesis was found to have a mean value of 10−5.17.