bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacteria in a hospital nursery: laboratory and clinical studies
Authors: Winton F. W. , Keay A. J. 
Published: May 2009

SummaryTwo hundred and twenty-two infants and fifty-one staff were examined for carriage ofStaphylococcus pyogenesand Gram-negative bacilli, and the presence of these bacteria in the ward environment was also investigated. Staphylococci were phage-typed and tested for sensitivity to antibiotics. Assessment of clinical infection caused by these bacteria was made.Infant carriage ofStaphylococcus pyogeneswas maximal on the sixth day, 73·1 % of umbilical swabs yielding significant growth. Carriage of Gram-negative bacilli was maximal on the fifth day, 31·7% of umbilical swabs being positive. Where special nursing was enforced, i.e. premature baby unit, isolation of Gram-negative bacilli was very infrequent.The low nasal carriage of staphylococci seen in infants and nursing staff is attributed to traces of penicillinase-resistant penicillins in the ward air.Staphylococcus pyogeneswas recovered from 23 % of ward surfaces, and constituted 0·7% of the air-borne flora. In contrast, Gram-negative bacilli were recovered from 4·7 % of surfaces, and composed only 0·15% of the air-borne flora.Phage group I constituted 73·0, 44·9 and 41·2% of strains from infants, staff and ward environment respectively.Antibiograms were grouped into three categories, A, B and C. Category A (sensitive to chloramphenicol, erythromycin and methicillin but penicillin-resistant) composed 79·0% of infants' strains, being found mostly in group I, but was rare among staff strains.Of 54 specimens taken from 40 infants showing evidence of infection,Staphylococcus pyogeneswas isolated from 16, of which 14 were category A. Gram-negative bacilli were isolated 7 times. Only 21 infants required antibiotic therapy (9·3%) and none were infected with Gram-negative bacilli—this contrasts with the frequency of these bacilli in nursery infection today.Ward air is considered to be the maindepotofStaphylococcus pyogenes. Infant ‘dispersers’ are probably the principalsourceof the air-borne staphylococci. Infants and staff abstract from the air those staphylococci which become their colonizing strains. No transfer is thought to occur from the staff to the infants. Transmission of Gram-negative bacilli is similar in that the infants are the principal source and the air the maindepotof these bacteria. Nasal colonization by Gram-negative bacilli is low, this is possibly due to poor colonizing properties. Infant umbilical carriage almost certainly results from endogenous faecal spread.We are grateful to Dr J. C. Gould, Director, Central Microbiological Laboratories, Edinburgh, for his continued interest and advice, and to Mr J. C. Ferguson and Mrs M. M. Winton for skilled technical assistance. This study would not have been completed without the co-operation of Sisters McCartney and Struthers and their nursing staff.
Langat virus encephalitis in mice I. The effect of the administration of specific antiserum
Authors: Webb H. E. , Wight D. G. D. , Platt G. S. , Smith C. E. G. 
Published: May 2009

Summary1. When mice are infected intraperitoneally with Langat virus only a small proportion develop clinical encephalitis, but all mice have substantial titres of virus in the brain and also incontrovertible histological evidence of encephalitis.2. When specific antibody is given intraperitoneally or intravenously to mice during the first 3 days after intraperitoneal infection with Langat virus, the viraemia (normally maximal during this period) is depressed, the production of antibody is depressed or delayed, and the incidence of clinical encephalomyelitis is increased significantly.3. Specific antibody given intraperitoneally or intracerebrally before infection, protects the animals from encephalitis.4. These findings are discussed in terms of the histology of the central nervous system of the affected mice.We are very grateful to Miss S. J. Illavia, B.Sc., and to Miss G. E. Fairbairn for their skilled technical assistance; and to Mr S. Peto of the Microbiological Research Establishment for statistical advice.This work was made possible by a generous grant from the Wellcome Trust and the Endowment Funds of St Thomas's Hospital
Elevated temperature incubation of enrichment media for the isolation of salmonellas from heavily contaminated materials
Authors: Harvey R. W. S. , Price T. H. 
Published: May 2009

SummaryIn three separate series, samples were examined for salmonellas by culture in selenite F broths incubated at 37 and 43° C. The samples used were:(1) Gauze swabs placed in sewage.(2) Gauze swabs placed in drains in abattoirs.(3) Sewage-polluted river water.In each series the higher temperature gave better results.The modification of tetrathionate broth for incubation at 43° C. and the adjustment of the incubation temperature to suit more inhibitory enrichment broths is discussed. The medium of Rappaport, Konforti & Navon (1956) is not suited to incubation at 43° C.We should like to acknowledge the help of Prof. Scott Thomson in the preparation of this paper, and the capable technical assistance of Mr T. R. Liddington and Mr John Morgan. We are also indebted to Dr H. Campbell, Senior Lecturer in Medical Statistics in the Welsh National School of Medicine, for his advice and to Mr M. C. Finniear, Deputy Public Analyst of the Glamorgan County Public Health Laboratory, for the calculation of molar tetrathionate in Rolfe's tetrathionate broth.
The epidemiology of respiratory infection in an isolated Antarctic community
Authors: Cameron A. S. , Moore B. W. 
Published: May 2009

SummaryThe results of a combined clinical and laboratory study of respiratory infections among members of an Australian Antarctic expedition are presented. Virus isolation and serological methods were employed, but the aetiological agent or agents responsible for respiratory infections in this group were not revealed.The clinical findings were correlated with published and unpublished studies on comparable communities, and the following broad pattern of the epidemiology of respiratory tract infections in such groups has emerged. The assembly on board ship of a party from widely separated areas often leads to infections after embarkation. On long voyages these infections may burn out, but frequently new cases are still appearing when the party arrives in Antarctica. Symptoms in sufferers at this time become more severe, suggesting that the sudden environmental change from the warmth of an air-conditioned ship to the harsher Antarctic conditions may influence the course of the respiratory infections. With isolation established in Antarctica, further cases rarely appear. On exposure to the relief party, however, infections can be expected, and it is noted that morbidity is usually low and symptoms are mild, indicating an apparent heightened resistance to infection in the acclimatized party while still on the ice.This study has further shown that most of these men, on returning to urban societies, contracted moderately severe upper respiratory tract infections in contrast to their apparent resistance when under Antarctic conditions.The suitability of these groups for experimental study, including the inoculation of volunteers, was discussed and suggestions were made for future work.
A new approach to development of live vaccine against tick-borne encephalitis
Authors: Smorodintsev A. A. , Dubov A. V. , Ilyenko V. I. , Platonov V. G. 
Published: May 2009

SUMMARYInvestigations of the biological properties of tick-borne encephalitis viruses immediately after isolation from naturally infected Ixodes persulcatus from Western Siberia has revealed their different pathogenicity for monkeys and mice. Strains highly pathogenic for mice on extraneural inoculation and for rhesus monkeys on intracerebral inoculation have been isolated, but also strains with a low extraneural pathogenicity for mice and a complete non-pathogenicity or a mild pathogenicity for monkeys on intracerebral inoculation.The viruses have been classified into three main groups by their virulence for mice and monkeys, and their ability to grow in tissue culture at 40° C. and the findings are summarized in Table 6. Group I included viruses highly virulent for mice by any route of inoculation, which caused fatal paralytic disease in monkeys, and which grew well in chick embryo culture at 40° C.Group II strains also had a high virulence for mice, but in monkeys caused milder disease with a peculiar clinical course indicative of primary damage to the cerebellum. About half of the infected monkeys recovered completely or with mild sequelae (ataxia, pareses of the limbs). This group grew moderately well in chick embryo cultures at 40° C. Groups I and III differed essentially in their virulence for mice by subcutaneous inoculation, and virulence for monkeys decreased distinctly with transition from group I to group III. Group III strains showed a lower reproduction rate at 40° C. In chick embryo culture than group I. Groups I and II showed good correlation between extraneural pathogenicity for mice, pathogenicity for monkeys by IC inoculation, and growth rate in chick embryo cultures at 40° C.Group I strains were isolated chiefly from foci with a high TBE morbidity and the strains of groups II and III in foci with sporadic cases. It is, however, highly probable that in any tick-borne encephalitis focus several variant strains of differing virulence exist.Recent experience of vaccinating volunteers with naturally attenuated group III strains suggests that safe and effective live vaccines can be developed against tick-borne encephalitis. Vaccines against many other arbovirus diseases can probably also be derived from naturally occurring strains of virus isolated from arthropods in areas of low disease but high infection rate. This approach looks more promising than the usual approach of attempting to develop attenuated strains from highly virulent strains.
Protection from microbial contamination in a room ventilated by a uni-directional air flow
Authors: Lidwell O. M. , Towers A. G. 
Published: May 2009

SUMMARYExperiments have been carried out on the extent to which movement of persons in a room ventilated by a horizontally directed uniform air velocity can transport airborne bacteria from one position to another. More than 107 particles approximately 13 μ in diameter (settling rate in air about 1 ft./min.) carrying spores of Bacillus subtilis var. niger were liberated in each experiment and the numbers reaching the different parts of the room were estimated by those recovered on exposed settling plates. At air velocities of 35 ft./min. and over, no particles could be certainly found to have moved against the direction of air flow except into areas actually entered by persons, and the numbers found in these areas were between 100 and 1000 times less than would have been expected in rooms turbulently ventilated with the same volume of air. There was some transport of particles transversely across the air-flow lines but at 4 ft. distance from the area where movement of persons was taking place the numbers had fallen substantially below 1/100 of those to be expected in a turbulently ventilated room.The results recorded at an air velocity of 22 ft./min. were significantly less satisfactory.Our thanks are due to the N.W. Metropolitan Regional Hospital Board, to the Hospital Management Committee of St Charles' Hospital, London, W10, and especially to the hospital engineer for accommodating the experimental room and facilitating its operation.
Frequency of rubella antibodies among adult population in Greece
Authors: Papaevangelou George J. 
Published: May 2009

SUMMARYNo significant sex difference in the incidence of immunity to rubella at the ages of 20–25 was found in a comparative study of young adults from the Greater Athens area as well as from the rural department of Corinthia. The immunity to rubella of Greek adults on a national scale was then studied in a respresentative sample of 1200 males 20–25 years old. In 83·2% of them neutralizing antibodies to rubella were detected. A statistically higher proportion of immunes was found among those from urban areas. The factors responsible for the relative prevalence of immunity to rubella in various population groups are discussed.
A selective motility medium for routine isolation ofSalmonella
Authors: Harper J. , Shortridge K. F. 
Published: May 2009

SUMMARYA modified Shigella—Salmonella medium in semi-solid agar was shown to inhibit the spread of most faecal organisms through a Craigie tube, while selectively allowing the passage ofSalmonella.A medium for routine use is described.Over a period of 3 years, in this laboratory, 90% of specimens from which salmonellas were isolated gave positive results with this medium. Over 40% of these specimens would have been reported as negative if the method had not been in use. However, 10% would have been missed if this method alone had been used. It should therefore be used in conjunction with other culture methods, of which direct plating on SS agar was the most successful in this series.
Antibody against influenza A2 virus neuraminidase in human sera
Authors: Schild G. C. , Newman R. W. 
Published: May 2009

SUMMARY1. High titres of neuraminidase-inhibiting antibody were detected in convalescent human sera following natural influenza A2 infections.2. Such antibody was encountered infrequently in acute serum samples. Antibody persisted only 5–6 months after infection in the four individuals from whom serial serum specimens were available.3. Following immunization with killed influenza virus vaccines (with adjuvant) neuraminidase inhibiting antibody was detected in human sera. The titres were in general lower than those detected in convalescent human sera.4. The specificity of the neuraminidase-inhibiting antibody in human and animal antisera was studied. Tests with convalescent human sera using purified neuraminidase preparations and with a recombinant virus containing A2 neuraminidase and haemagglutinin distinct from that of human influenza A viruses enabled the conclusion that the antibody detected was specific for influenza A 2 neuraminidase.We wish to thank Dr D. A. J. Tyrrell of the Clinical Research Centre, Mill Hill, London, for human serum specimens, Dr D. Breeze of Evans Medical Ltd., Liverpool, for sera from an influenza vaccine trial and Dr M. S. Pereira of the Public Health Laboratory, Colindale, London, for serial serum samples from persons who had influenza in 1957. Dr M. S. Pereira carried out the haemagglutination-inhibition tests and complement fixation tests on these sera.We are grateful to Dr H. G. Pereira and Dr D. A. J. Tyrrell for valuable discussions during the course of this study, and to Professor C. H. Stuart-Harris for his comments on the manuscript.
Quantitative aspects ofMycoplasma pneumoniae-cell relationships in cultures of lung diploid fibroblasts
Authors: Larin N. M. , Saxby N. V. , Buggey D. 
Published: May 2009

SUMMARYThe FH strain ofMycoplasma pneumoniaewas studied in experimentally infected cultures of lung diploid fibroblasts. The multiplicity of infection was found to have a profound influence on the distribution of the cell-associated and extra-cellular mycoplasmas. At a high multiplicity there was very little difference between the ratio of cell-associated and extracellular mycoplasmas. In contrast, with a low multiplicity the cell-associated mycoplasmas predominated and with further reductions of the inoculum only the cell-associated mycoplasmas could be detected. The significance of these findings is discussed. It is suggested that caution has to be exercised in the determination of the potency of antibiotics against mycoplasma by methods employing acellular media alone, and it is desirable to utilize also appropriate cell culture models. A possible approach to designing such models is provided by this study.We express our appreciation to the Tissue Culture Laboratory, Pfizer Limited, Sandwich, for kindly supplying us with cell cultures. We furthermore thank the Board of Directors, Pfizer Limited, for permission to publish this study. The helpful discussions with our colleagues Drs D. Jackson and G. M. Williamson in preparing the manuscript are acknowledged with thanks.
Bacterial contamination on the surface of hospital linen chutes
Authors: Whyte W. , Baird G. , Annand R. 
Published: May 2009

SUMMARYA survey of 13 linen chutes in eight hospitals was carried out to assess the amount of bacterial contamination on the inner walls of these chutes. It was shown that the average bacterial count in these chutes was low by general hospital standards (19·7 bacterial colonies per Rodac plate). This concentration was eight times less than the average concentration found on the floor surface at each linen disposal and collection point (153 bacterial colonies per Rodac plate).Three chutes sampled during the survey were periodically cleaned but appeared to derive only very limited benefits from the cleaning method they used.Tests carried out on three linen chutes showed that the bacterial surface contamination of a sterilized chute could normally reach a maximum concentration in a period of between 4 and 24 hr.It is concluded that so long as good engineering practices are used in the construction of linen chutes the bacterial contamination on their inner surface should not contribute to the problem of hospital cross infection. For this reason, and because of the impracticability of sterilizing linen chutes at very short intervals of time, it is considered that cleaning of chutes would serve no practical purpose.Thanks must be recorded to the authorities of all those hospitals who gave their permission for us to study their linen disposal chutes and afforded us every assistance.We should also like to thank Mr W. Carson, Leader of the Building Services Research Unit, for his help and encouragement.The work reported was a part of an investigation into the design of linen disposal chutes sponsored by the Western Regional Hospital Board, Scotland.
Haemorrhagic smallpox
Authors: Downie A. W. , Fedson D. S. , Vincent L. St , Rao A. R. , Kempe C. H. 
Published: May 2009

SUMMARYIn practically all acute fulminating smallpox infections—haemorrhagic type I cases—there is severe viraemia with 104 or more infective particles of virus per ml. of blood. In most of these patients soluble antigen can be demonstrated in serum by precipitation in agar gel tests, or by the complement-fixation technique. In late haemorrhagic cases (type II) the degree of viraemia is less and soluble antigen is less often demonstrated in the blood. Five of forty type II patients recovered. The majority of the 77 patients studied were adults and bore scars of previous vaccination. Thirteen were pregnant women and 10 of these suffered from type I infections.The antibody response in patients who survived 6 days or longer as determined by the estimation of precipitins, CF antibodies and neutralizing antibodies in serum, was considerably less than that seen in non-haemorrhagic smallpox patients.In acute fulminating smallpox infections, the finding of virus or soluble antigen in the blood is of value in establishing the diagnosis. Soluble antigen is usually found in the blood of patients suffering from severe viraemia and with the methods used has been demonstrated only in patients who are to die of their disease. Haemorrhagic smallpox represents a generalized virus infection of unusual severity in patients who show little resistance to their infection. The cause of this unusual susceptibility is unknown but there is little evidence that specific allergy to the virus is a feature of this form of the disease.This investigation was supported in part by Public Health Service Grant AI–1632–16 VR from the National Institute of Allergy and Infectious Diseases, by the World Health Organization and by the Marcus T. Reynolds III Fund.
Conjunctivitis and subclinical infection in smallpox
Authors: Kempe C. H. , Dekking F. , Vincent L. St , Rao A. R. , Downie A. W. 
Published: May 2009

SUMMARYAttempts were made to demonstrate variola virus in the conjunctival exudate of 84 smallpox patients who developed conjunctivitis in the acute stage of the illness or during convalescence. Variola virus was isolated from 60 but not from the remaining 24. Of the 64 from whom virus was isolated the conjunctivitis developed from the onset up to the 15th day of illness. From conjunctivitis developing later virus was not recovered. In some patients who developed conjunctivitis early in the disease we failed to recover virus from the conjunctival exudate.Of 55 close family contacts who stayed in hospital with smallpox patients four developed smallpox. In 21, conjunctivitis but no other illness developed. From 12 of these, variola virus was recovered from the conjunctival exudate and four of these 12, who were further investigated, showed after the appearance of conjunctivitis antibody titres similar to those seen in typical smallpox cases. From nine of the contacts who developed conjunctivitis virus was not recovered. One of these had antibody titres in serum collected before the onset of conjunctivitis which indicated recent smallpox infection. In another there was a marked antibody rise during her hospital stay although examination of conjunctival exudate on three separate occasions failed to yield variola virus. Twenty-six family contacts who developed no illness in hospital had antibody determinations made on sera collected soon after admission to hospital. In eight of these antibody titres were such as to indicate recent smallpox infection although there were no signs, in the form of scarring, or history of recent smallpox infection. These findings have been discussed in relation to the occurrence of minimal and subclinical infection in close family contacts of smallpox patients.This investigation was supported in part by Public Health Service Grant AI–1632–16 VR from the National Institute of Allergy and Infectious Diseases, by the World Health Organization and by the Marcus T. Reynolds III Fund.
A survey of infectious mononucleosis in the North-East Regional Hospital Board area of Scotland, 1960–9
Authors: Davidson R. J. L. 
Published: May 2009

SUMMARYThis report, based largely on 1258 laboratory proven cases of infectious mononucleosis (IM) detected in the North-Eastern Regional Board area of Scotland during the years 1960–9 inclusive, describes and discusses some of the epidemio-logical and diagnostic aspects of the disease.During the period of study, the annual rate of incidence increased fourfold from 11·1 to 44·3 cases per 100,000 population. Evidence is presented to indicate that this does not represent a true increase in prevalence but reflects improvements in disease detection. The annual incidence rates as reported by the C.D.S. for 1967–9 inclusive are regarded as a considerable underestimation of the ‘true’ incidence of the disease. Over a 3-year period an annual incidence equivalent to 100 per 100,000 population was found in each of two selected group practices. This value was constant and is thought to approximate the ‘ true’ incidence of symptomatic, seropositive IM in the general community.Of the 1258 seropositive cases, 48·7 % were males and 51·3 % females. The peak age incidence was 15–19 years for both sexes. Twenty-one per cent of the cases were in children under 15 years and only 8·1 % in adults older than 25 years. No significant variation was found in the seasonal or urban/rural incidence. Marked differences were found in the leucocyte patterns of seropositive and ‘seronegative’ cases.