bluuebunny/crossref_metadata_2025 huggingface dataset:
e-Antigen: a link between immune response and infectivity in hepatitis B?
Authors: Turner G. C. , Green Helen T. , Blundell Vivian D.
Published: May 2009

In a study of the distribution of e-antigen and anti-e in subjects whose blood was positive for hepatitis B surface antigen (HBsAg), patients with acute hepatitis B who were tested during the incubation period were all e-antigen-positive but after the onset of illness e-antigen was detected in only 11%. Persistence, and in some instances reappearance of e-antigen in those who became long-term carriers of HBsAg was associated with high titres of HBsAg. There was a high incidence of e-antigen in those conditions in which cell-mediated immunity may be depressed, including Down's syndrome and chronic renal failure.

The majority of HBsAg carriers identified as sources of infection were e-antigen-positive. A positive reaction for e-antigen is evidently associated with a defective immune response to hepatitis B virus infection which permits continued replication of virus in liver cells accompanied by high titres of HBsAg, numerous Dane particles and detectable DNA polymerase in the blood with consequently a greater likelihood of transmitting infection.

Although it cannot be assumed that anti-e positive carriers of HBsAg are not infective, it may be necessary, in the assessment of passive or active immunization for the control of hepatitis B, to take into account the e-antigen/antibody status of possible sources of infection.
Excretion of foot-and-mouth disease virus in oesophageal-pharyngeal fluid and milk of cattle after intranasal infection
Authors: de Leeuw P. W. , van Bekkum J. G. , Tiessink J. W. A.
Published: May 2009

The virus growth in the pharyngeal area and the virus excretion in milk of susceptible and vaccinated dairy cows after intranasal instillation of foot-and-mouth disease (FMD) virus type O1 were examined. Ten vaccinated cows were purchased through a market. Of these, nine had delivered their first calf. The cows were inoculated 2–9 months after having received the last dose of vaccine. All vaccinated cows resisted the intranasal challenge. The virus multiplied in the pharyngeal area but, compared with two susceptible controls, to a limited extent. No clear relation was found between virus growth and the titre of circulating neutralizing antibody at the time of challenge.

Virus was first detected in milk samples of the susceptible cows when generalized FMD lesions had developed on day four; the excretion lasted for 3–4 days.

Up to 19 days after inoculation untreated milk of the vaccinated cows was examined for the presence of infectious FMD virus. Samples were inoculated onto cell cultures, fed to susceptible pigs and calves and injected intramuscularly and/or intradermolingually into susceptible steers. No infectious FMD virus could be detected, either in cell cultures or in susceptible animals. The animals did not develop neutralizing antibody against FMD virus and were subsequently shown to be fully susceptible to challenge. The results are discussed with particular reference to current problems regarding the export of milk products from countries where vaccination against FMD is practised to countries free of the disease.
Epidermal tissue as a primary site of replication of lymphocytic choriomeningitis virus in small experimental hosts
Authors: Skinner H. H. , Knight E. H.
Published: May 2009

When fresh urine from LCM tolerantly infected mice was applied to small areas of excoriated skin of guinea-pigs undiluted or diluted 10−1, a high LCM infectivity developed in the local dermal tissue within 3 days and quickly spread to the lymphatic system. The skin at this site of infection became erythematous 10–12 days after infection and a few days later a rash was often seen in the hairless skin around the mammary teats. A viraemia was first detected at about 8 days after infection and persisted for at least 8 days, during which time a high infectivity titre in skin not only at the infection site but also distal to it suggested that there was a generalized active infection of the dermis. Infectivity in the tongue was simultaneously high and probably associated with erosions of the tongue tip seen a day or two later than the teat rash.

In similar experiments in hamsters and rabbits, indications were again that lightly injured dermis was a primary site of virus replication. These observations should lead to the dermal route receiving greater attention as a potential route of infection of man when exposed to infectious excretions of reservoir hosts of arena-viruses.
Nosocomial klebsiellas: I. Colonization of hospitalized patients
Authors: Haverkorn Michael L. , Michel M. F.
Published: May 2009

The colonization of patients byKlebsiellaand several other gram-negative bacteria was studied in a hospital urological ward over a period of six months. Before and during the survey there was no evidence of an outbreak of nosocomial infection and multi-drug resistant strains ofKlebsiellawere not isolated.

Klebsiellawere biotyped by nine biochemical tests, which led to the detection of 66 biotypes spread uniformly throughout the survey period. This method of biotyping proved a useful epidemiological tool. The colonization rate of throats, hands, and faeces of patients increased after admission to the ward, especially when antibiotics were used. The effect of systemic antibiotics was greater than that of urinary antibiotics especially on throat and faeces carrier rates. Carrier rates forKlebsiellaincreased also after catheterization and operation – relationships which could well be multifactorial.

During the first two weeks after admission the proportion of antibiotic resistant strains ofKlebsiellain carriers increased. The proportion of resistant strains amongst isolations from clinical infections was always greater than among strains isolated routinely from sites of carriage.
The effect of long-term exposure to cigarette smoke on the height and specificity of the secondary immune response to influenza virus in a murine model system
Authors: Mackenzie J. S. , Flower R. L. P.
Published: May 2009

The effect of long-term exposure to cigarette smoke on the height and specificity of the secondary humoral immune response to influenza was investigated in a murine model system. It was shown that if mice were pre-immunized with a sub-lethal infection of influenza virus and then exposed to cigarette smoke daily for 36 weeks, they were able to mount a secondary immune response of normal height on subsequent challenge with the homologous virus strain. The response, however, was less specific than that elicited in control mice, with high titres of cross-reacting antibody by haemagglutination-inhibition to the following strain in the same antigenic series. Recall of antibody to the previous strain in the antigenic series was not observed in either control or smoke-exposed animals. These results serve to correct an earlier discrepancy between the murine system and human studies in which the response to influenza infection in mice was depressed by prolonged exposure to cigarette smoke, whereas in man the response of smokers did not differ significantly from that of non-smokers. This apparent discrepancy had been caused by a lack of previous experience of influenza in the mice, which had therefore mounted a primary response, compared with the secondary response observed in the human studies.
The Brown Animal Sanatory Institution
Authors: Wilson Sir Graham
Published: May 2009

As mentioned in Chapter 1, the Brown Institution was staffed by a remarkable series of Superintendents, seven out of eight of whom were, or became, Fellows of the Royal Society. Much of the research work they undertook has already been referred to in preceding chapters, but it seems only fitting that something should be said about their personalities and careers. In preparing the short accounts that follow, I am greatly indebted to obituary notices in the various scientific journals, especially those in the Proceedings of the Royal Society; to the pen sketches given by Professor Sharpey-Schafer (1927) in his History of the Physiological Society;and to the Memoirs in book form of Sir John Burdon-Sanderson by his wife (1911)and of Sir Victor Horsley by Sir Stephen Paget (1919).
Measles in monkeys: an epidemiological study
Authors: MacArthur J. A. , Mann P. G. , Oreffo V. , Scott G. B. D.
Published: May 2009

summary

This study describes aspects of measles in non-human primates. Monkeys infected before importation are shown to produce non-immune offspring in captivity in England. The high antibody titres found in most recently imported monkeys decline slowly during captivity in England. While measles is often fatal to monkeys, we have described an outbreak in which a number of symptomless infections occurred. Histological examination of fatal cases produced evidence of infection in the wall of the urinary bladder in one monkey. The close similarity between measles in humans and monkeys has been confirmed. It is considered that the study of infection among the latter may have significance for the former.
Food poisoning in hospitals in Scotland
Authors: Sharp J. C. M. , Collier P. W. , Gilbert R. J.
Published: May 2009

summary

A review of 50 hospital-based outbreaks of food poisoning which were reported in Scotland during 1973–7, is described. At least 1530 persons consuming hospital-prepared food were involved. Thirty-one episodes were associated with Clostridium perfringens (C. welchii), 11 were due to food-borne salmonella infection, three to enterotoxigenic Staphylococcus aureus, and five incidents were of undetermined aetiology. This differs noticeably from the experience in England and Wales where salmonellas appear to predominate as the main cause of hospital outbreaks. Twenty-two incidents occurred in hospitals for psychiatric or mentally subnormal patients, and ten others were located in geriatric units. Only 33 hospitals were involved in the 50 outbreaks as nine hospitals experienced two or more episodes.

The role of the hospital in the occurrence of food poisoning may be over-emphasized in comparison with other catering establishments, as outbreaks are more readily recognized and laboratory facilities are usually available for investigation, but it is also believed that many episodes may not be reported. The peculiar problems of the hospital-catering service and particularly those of the older long-stay hospitals, are discussed in relation to preventive measures which would minimize the hazards of food poisoning.
The effect on the virulence and infectivity ofSalmonella typhimuriumandSalmonella gallinarumof acquiring antibiotic resistance plasmids from organisms that had caused serious outbreaks of disease
Authors: Williams Smith H. , Tucker J. F.
Published: May 2009

summary

Antibiotic resistance plasmids from organisms that had caused serious epidemics, including those responsible for epidemics of chloramphenicol-resistant typhoid fever and dysentery in Central America, were transferred to a strain ofSalmonella typhimuriumand ofSalmonella gallinarum. The virulence and infectivity of these R+forms were then compared with the R−parent forms in orally inoculated chickens.

None of the R+forms were more virulent than their R−parent forms. The mortality rates they produced were either the same as or less than that of their R−parent forms. The mortality rates were not increased by feeding the chickens on diets containing antibiotics against which the plasmids provided resistance.

The removal of the plasmids from some R+forms of decreased virulence was not accompanied by any alteration in virulence, indicating that they were less virulent mutants of the parent strain that had conjugated preferentially. In other cases their virulence was increased, indicating that the very possession of the plasmid was involved in their decreased virulence. Of four forms of theS. gallinarumstrain harbouring the plasmid that had been incriminated in the Central American dysentery outbreak, one was as virulent as the parent R−form and the other three were less virulent. Preferential conjugation by an avirulent mutant was responsible for the lack of virulence of one of them but the very possession of the plasmid appeared responsible for the decreased virulence of the other two. The decreased virulence of de-repressed F+and I+forms of theS. typhimuriumstrain was increased to that of repressed F+form and of the parent form by plasmid removal.

Organisms of the R+forms of theS. typhimuriumstrain were not excreted in larger amounts or for longer periods of time by infected chickens than organisms of the R−parent form were. Neither did organisms of the R+forms of this strain or theS. gallinarumstrain spread more rapidly or more extensively from infected chickens to in-contact chickens than organisms of the R−parent forms did. When antibiotics against which the infecting R+organisms provided resistance were included in the diet of these chickens the R+organisms were usually excreted in greater amounts, for longer periods of time and spread more rapidly and more extensively from the infected chickens to the in-contact chickens.
The antibody response in Legionnaires' disease
Authors: Nagington J. , Wreghitt T. G. , Tobin J. O'H. , Macrae A. D.
Published: May 2009

summary

From 22 patients with Legionnaires' disease, 86 sera were examined for specific serotype 1 IgM and IgG antibodies by the indirect immunofluorescence technique.

No antibody was detectable until 8 days or more from the onset of symptoms. When produced the amount was widely variable and remained detectable for periods from less than 34 days to more than 1 year.

Initially IgM antibody predominated, ten patients produced only IgM in the first 21 days, six produced only IgM in the first 28 days and three did not produce IgG at any time. One patient, and possibly a second, produced only IgG antibody.

Since IgM antibody was still present in one patient after a year it is important not to accept the presence of this as evidence of very recent infection.

It is advisable that any type of serological test for L. pneumophila infection should detect the production of both IgM and IgG antibodies.
Antibody studies in natural bovine cowpox
Authors: Baxby Derrick , Osborne A. D.
Published: May 2009

Serological studies on cows recovered from natural cowpox indicated that Haemagglutinin-Inhibiting (HAI) antibody persisted for at least 27 weeks, and Virus Neutralizing (VN) antibody persisted for at least 98 weeks.
Incidence of bluetongue virus precipitating antibodies in sera of some domestic animals in the Sudan
Authors: Eisa M. , Karrar A. E. , Elrahim A. H. Abd
Published: May 2009

To determine the presence and prevalence of bluetongue (BT) infection in a variety of domestic animal species in different geographical regions of the Sudan, a serological study using the agar gel precipitation technique was initiated. A total of 2142 serum samples were examined. Of the numbers tested approximately 28% of sheep, 11.2% of goats, 8% of cattle and 4.9% of camels were positive for group-specific antibodies to BT virus antigen, indicating previous exposure to BT infection. None of the samples tested from horses or donkeys were positive. The findings suggest that the disease is widely distributed in most parts of the Sudan where possible insect vectors prevail and may be endemic in sheep in Juba District, Equatoria Province, Southern Region. Goats appeared to have some degree of resistance to infection compared with sheep, and there seemed to be no significant differences in positive rates between farm and free-range cattle.

It is concluded that BT infection may cause clinical disease in sheep, while it is probably subclinical or inapparent in goats, cattle and camels of the Sudan.
A bacteriological survey of sanitary dressings, and development of an effective means for their disposal
Authors: Lucas C. M. , Mendes M. F.
Published: May 2009

A microbiological survey of over 400 sanitary dressings is reported: large numbers of bacteria are present, including species indicative of faecal contamination. The need for an effective bactericide in chemical bin exchange systems is thus demonstrated. Screening trials of several candidate formulations have been undertaken: buffered sodium metabisulphite, releasing sulphur dioxide as a vapour-phase bactericide, has now been introduced as an effective bin exchange system.
Inactivation of viruses in municipal effluent by chlorine
Authors: Hajenian H. G. , Butler M.
Published: May 2009

The influence of pH arid temperature on the efficiency of chlorine inactivation of two unrelated picornaviruses in a typical urban wastewater effluent was examined. Temperature, unlike pH, had relatively little effect on the rate of inactivation. The pH effect was complex and the two viruses differed. The f2 coliphage was more sensitive to chlorine at low pH, but at all values there was a threshold above which additional chlorine resulted in very rapid inactivation. The amount of chlorine required for this was less at low than at high pH, although at pH values above 7 the extent of inactivation was about the same. There was no apparent correlation between pH and rate of inactivation of poliovirus but there was a suggestion that at a pH close to the isoelectric point of the virus it was less sensitive to chlorination.
Contaminated medicaments in use in a hospital for diseases of the skin
Authors: Baird Rosamund M. , Awad Z. A. , Shooter R. A. , Noble W. C.
Published: May 2009

Topical medicaments used by patients with diseases of the skin were examined for microbial contamination. Ps. aeruginosa was isolated from stock pots of a diluted emulsifying ointment used as a soap substitute in the bath. Cross-con tamination between patients and medicament was subsequently shown to have occurred.
Further observations on the effect of feeding diets containing avoparcin, bacitracin and sodium arsenhlate on the colonization of the alimentary tract of poultry by salmonella organisms
Authors: Smith H. Williams , Tucker J. F.
Published: May 2009

The continuous administration of food containing 10 mg/kg of avoparcin to groups of 28 chickens in contact with five chickens experimentally infected with a nalidixic acid-resistant (nalr) mutant of a salmonella strain strongly favoured the colonization of their alimentary tracts with salmonella organisms. Bacitracin, 10 mg/kg, either had no effect or only slightly favoured salmonella colonization and sodium arsenilate usually hindered it.
Aspects of heat inactivation of foot-and-mouth disease virus in milk from intramammarily infected susceptible cows
Authors: Leeuw P. W. De , Tiessink J. W. A. , Bekkum J. G. Van
Published: May 2009

In skim milk obtained from susceptible cows after intramammary and intravenous inoculation (primary infected milk), foot-and-mouth disease (FMD) virus type 01was slower inactivated by heat treatment than virus that had been added to pre-exposure skim milk.

Residual virus infectivity in heated primary infected milk was more efficiently detected in bovine thyroid cell cultures than in secondary pig kidney (PK2) cell cultures.

Untreated primary infected milk was found to inhibit both FMD-virus and vesicular stomatitis virus plaque formation in PK2cells, suggesting the presence of interferon. The results of further tests confirmed that the interfering activity in unheated primary infected milk was indeed caused by an interferon.

Interferon excretion in primary infected milk was investigated using a series of milk samples from three cows. Maximum interferon titres were found after 24 h, coinciding with or shortly after the first virus excretion peak. The results are discussed with particular reference to the use of primary infected milk in studies of the thermal inactivation of FMD-virus.
Isolation and classification of sixteen strains of saprophytic leptospires
Authors: Cinco M. , Coghlan J. D. , Matthews P. R. J.
Published: May 2009

Sixteen strains of leptospires were isolated from surface water (14 in England and 2 in Italy) and were classified. They were all saprophytic, and nine of them belonged to known serovars: the others were found to represent new serovars within already known serogroups.
Commercial milk products and indigenous weaning foods in a rural West African environment: a bacteriological perspective
Authors: Barrell R. A. E. , Rowland M. G. M.
Published: May 2009

Two commercially available baby milks, one ‘biologically acidified’, the other ‘non-acidified’, and a traditional weaning food, millet gruel, were prepared and stored under village conditions in West Africa. Increases in total colony count and in number ofBacillus cereus, Clostridium welchii, Staphylococcus aureusandEscherichia coliwere determined in these products when stored as commonly practised at ambient temperatures over a period of 8 h. Poor hygiene during preparation was indicated by readily detectable numbers of coliforms andE. coliin freshly prepared samples of each of the milks, though the cooked local gruel seemed less vulnerable in this respect. The rate of increase in the numbers of these organisms was lower in the acidified milk when prepared with unboiled water containing high numbers of coliforms andE. coli. Increases in total colony count and in numbers ofStaph. aureuswere also less marked in the acidified milk. When food was not eaten soon after preparation the problem of bacterial overgrowth was as great with the local gruel as with the considerably more nutritious reconstituted milks.
Isolation and properties of an RNA fraction present inBrucellaculture supernatants
Authors: Corbel M. J. , Brewer R. A.
Published: May 2009

The supernatant fluids of batch and continuous cultures ofBrucellastrains contained up to 100 mg/i of soluble RNA which could be recovered by precipitation with lysozyme. This RNA fraction had many of the properties of ribosomal RNA and was single-stranded, sensitive to ribonuclease, with an approximate sedimentation constant of 5S, a molecular weight of about 35000 daltons and an adenine; guanine; cytosine; uracil content of 17·5 26·5 33; 23 mol% respectively. RNA fractions from lysozyme precipitates evoked high titres ofBrucellaagglutinins on injection into rabbits and induced acute inflammatory responses in guinea-pig skin. Highly purified RNA fractions prepared by phenol extraction of lysozyme precipitates did not evoke antibodies toBrucella abortus.
The epidemiological type identification ofSerratia marcescensfrom outbreaks of infection in hospitals
Authors: Pitt T. L. , Erdman Y. J. , Bucher C.
Published: May 2009

A study of serological, bacteriocine and phage typing ofSerratia marcescenswas made. Specific O-antisera of adequate titre were relatively simple to prepare but H-antisera exhibited many heterologous agglutination reactions amongst the type strains. Most of these cross-reactions were not reproduced when immobilization tests with H-sera were performed. Direct haemagglutination tests were used to establish the presence of fimbriae amongst the H-type strains and the results of agglutination tests with non-fimbriate variants of strains indicated that fimbrial antibody in high titre was present in some sera.

Replicate typing of 100 pairs of cultures by the phage-typing method indicated that small variations in pattern were common and that larger variations occurred occasionally. Therefore differences in pattern of less than two strong reactions should not be taken as evidence that strains can be distinguished.

Cultures ofS. marcescens, 273 in total, from six outbreaks of infection in British and European hospitals were typed by O-serology, H agglutination and immobilization tests, phage typing and bacteriocine susceptibility by a cross-streaking method. The typability of strains by each method was high but the results suggested that no single method was sufficiently discriminating to be used alone for typing. Comparison of the H-type and typing patterns of members of the same O serogroup from incidents of infection showed that reliable results were obtained by H-typing or by phage and bacteriocine typing after the application of the appropriate ‘difference’ rule.

The greatest discrimination between strains of the same 0-group was obtained by the use of H-typing or phage typing.
The Northumberland epidemic of foot-and-mouth disease, 1966
Authors: Sellers R. F. , Gloster J.
Published: May 2009

The spread of foot-and-mouth disease during an epidemic in Northumberland in July, August and September 1966 was analysed. Although strong emitters, for example pigs, were not involved, in 18 of the 32 outbreaks spread could be attributed to the airborne route and in another 4, spread by this route was the most likely. Airborne spread was in general between 1 and 8 km but on two occasions as much as 20 km. Other means of spread included movement by animals, people and vehicles and carriage of virus between animals in neighbouring fields. No spread by milk or milk lorries took place. Sheep were involved in 9 farms; on each, lesions older than 48 h were found and it is likely that the sheep were the source of virus for other animals, especially cattle, on the farm and on neighbouring farms. The analysis suggests that control measures such as slaughtering direct contacts, as used in this epidemic, or ring vaccination as well as movement control would be effective in limiting spread.
Immunity to salmonella infection in mice
Authors: MacLeod D. R. E.
Published: May 2009

Experiments on immunity produced by vaccine were carried out in mice with two strains of salmonella.

Against intraperitoneal challenge protection was such that 40–80 % of vaccinated mice survived a dose that killed almost all controls. This level of immunity appeared to be maintained with little change for at least 5–7 months. An explanation for this stability is suggested.

Against infection by the natural route, either by direct feeding or by exposure to infected animals, protection from vaccine was of a comparatively low order.

Resistance to infection by an artificial route was, therefore, not a measure of resistance to infection by the natural route.
Titration of the virus of foot-and-mouth disease in culture
Authors: Brooksby J. B. , Wardle Ella
Published: May 2009

A technique is presented for the titration of the virus of foot-and-mouth disease in culture in surviving epithelial tissue from the tongues of cattle. The cultures are incubated in cups on Perspex plates, and the detection of virus multiplication is by a complement-fixation test made on the culture in each cup.

On the basis of comparative titrations in culture and in cattle, the method has been found to be as sensitive for the detection of virus as the titration by intradermal inoculation of the tongue of cattle. The method can also be applied in the detection of antibody in neutralization tests.

We wish to record our thanks to Messrs E. Scoates and P. Mitchell for their technical assistance, and to Messrs H. M. Smith, R. H. Compton and R. L. Jackson for their part in the design and fabrication of various bottle rotators, plate shakers, Perspex lids and the inoculating box.
Reactions of T Vi and Ballerup Vi haptenes with antisera against Vi-coated erythrocytes
Authors: Chu David Chi-Yen , Hoyt Robert K.
Published: May 2009

1. T Vi-coated rabbit erythrocytes, when injected into rabbits, stimulate the production of a (pure) Vi antiserum.

2. The T Vi extract was found to be heat-stable with respect to antigenicity and agglutinability, as shown by means of coated erythrocytes.

3. By means of cross-absorption tests it was shown that the Vi antigen of S. typhi differs from the Vi antigen of the Ballerup organism.

4. The need for caution in relying on resistance to heat as a character of groups of antigens is emphasized.

We wish to thank Dr P. R. Edwards, of the Communicable Disease Centre, U.S.P.H.S., and Dr Alcor S. Browne, California State Department of Health, for supplying certain of the cultures and specimens of typing serum used in these studies.
Factors affecting the formation and oxidation of sulphides in a polluted estuary
Authors: Wheatland A. B.
Published: May 2009

Factors affecting the formation and destruction of sulphide in the Thames Estuary have been discussed. Measurements of oxidation-reduction potentials show that the effect of oxygen in the water on conditions in deposits of mud is limited to the surface layer. The rate of formation of sulphide increases with temperature, doubling approximately for each 10° C. rise. Reduction of sulphate to sulphide will occur at temperatures as low as 5° C., but even at 25° C. is inhibited by traces of dissolved oxygen. Mud in suspension in the estuary can produce as much sulphide as compact layers of similar mud which might be more anaerobic.

Oxidation of sulphide in the Thames Estuary is shown to be of a purely chemical nature; the rate of oxidation, when oxygen is present, is increased by the presence of suspended matter and iron. In the Thames Estuary, however, the rate is limited by the rate at which oxygen enters the water.

Much of the experimental work described in this paper was carried out by Miss A. Laird, Mr A. E. Sutton and Mr R. B. Peel of this Laboratory. The paper is published by permission of the Department of Scientific and Industrial Research.
Serological studies during the 1953 epidemic of influenza A in New York State
Authors: Stuart-Harris C. H. , Gnesh Gladys M. , Gordon Irving
Published: May 2009

A number of workers have shown that antibodies to the influenza A viruses which are demonstrable in the sera of normal adults undergo periodic fluctuations in titre related to epidemic occurrence of the disease. The rise in antibodies accompanying infection and demonstrable by neutralization, agglutination-inhibition and complement-fixation tests is used as a method of diagnosis which is admitted to be of greater sensitivity than actual recovery of virus from the throat. Studies of the population during an epidemic have also revealed the existence of subclinical infection with rise in antibodies comparable to that occurring in those suffering clinical illnesses. But surveys of sera from large samples of the population show no general upward shift in antibody levels unless an actual epidemic occurs (Martin, 1940). The studies made by Francis, Magill, Rickard & Beck (1937), Hoyle & Fairbrother (1937), Rickard, Lennette & Horsfall (1940) and Martin (1940) also indicate the relative impermanence of the enhanced antibody levels consequent upon an epidemic. A relatively rapid decrease in antibody is shown both by the neutralization and complement-fixation tests during the 3–6 months after an epidemic and then a slower fall occurs until the next epidemic again causes a rise in titres. There have, however, been relatively few studies on large samples of populations situated in different geographical areas before and during an outbreak.
A comparison of the soluble antigen production by tissues infected with preparations of extracellular and intracellular influenza virus
Authors: Beale A. J.
Published: May 2009

1. The production of soluble antigen in the chorioallantoic membranes at 6 hr. can be used to measure the infectivity of influenza virus preparations.

2. Intracellular virus is much more infective when tested by soluble antigen production at 6 hr. than when tested by conventional methods.

3. It is suggested that intracellular virus differs from extracellular because more virus particles per cell are required to initiate infection.

The author is greatly indebted to Dr L. Hoyle for his advice and encouragement throughout this work. Mr G. Field gave valuable help with the mathematics.
The physique of Oxford undergraduates: Relationship With Weight Variation, Schooling and Habits
Authors: Parnell R. W.
Published: May 2009

In earlier reports on the physique of Oxford undergraduates attending the pilot student health service from 1947 to 1950 emphasis was laid on body shape. Parnell (1952) pointed out the tendency for centrally placed Sheldonian somato-types, that is those with more balanced mid-range body proportions, to occur more frequently in the Oxford sample than in American universities, a tendency incidentally which advances further according to the level of university performance attained. Tanner (1952) emphasized the tendency for Oxford students to show less mesomorphy, that is muscle and bone development, than American students but he reports a comment from Sheldon himself that the distribution at Harvard resembled the Oxford distribution more closely. This approach, by the analysis of body shape, to the problem of physical characteristics accompanying academic selection is of particular interest, but in calculating the somatotype, height is deliberately ignored by being placed as the denominator of all the body proportions employed. Height, however, is an index of body size, as opposed to body shape, and has an importance of its own. This report concerns observations on Oxford undergraduates in which more attention is paid to body size, and particular attention also to variation of weight during university residence.
A nomogram for 50 % end-point interpolation
Authors: Lim K. A.
Published: May 2009

In certain types of titrations the experimental results are obtained as percentages, say of mortality, at different dilutions in geometric progression of the test material. The result of a titration is then expressed as the 50% end-point which is estimated by interpolation as follows.
On the association of the pleuropneumonia-like organism L3 with bronchiectatic lesions in rats
Authors: Klieneberger Emmy , Steabben Dorothy B.
Published: May 2009

Data are presented which demonstrate a close connexion between the presence of the L3 organism and the pulmonary lesions of rats, but it has not so far been possible to produce the lung infection with the pleuropneumonia-like organism. The cultural and serological features of the L3 organism are given.
Reversed passive anaphylaxis in the guinea-pig
Authors: van den Ende M.
Published: May 2009

Attempts to demonstrate reversed passive anaphylaxis in the guinea-pig with crystalline egg albumin as sensitizing antigen have been uniformly negative.

When purified anti-pneumococcal antibody globulin was used as sensitizing antigen, reversed anaphylactic shock could be elicited in guinea-pigs by the intravenous injection of precipitins for the antibody globulin.

The mild reactions which could be elicited when the total globulins from the serum of normal rabbits were used as sensitizing antigen are probably dependent on the presence of small amounts ofyglobulin.

Reversed passive anaphylaxis, like direct anaphylaxis, is dependent on a cellular mechanism, and the success of experiments in which rabbit antibody globulin was used as sensitizing antigen depends on the acceptability of the antibody to the cells of the guinea-pig's tissues.

Antigenic differences between antibody globulins and total normal globulins from rabbit serum are noted.
A simple modification of Wilson and Blair's medium for the isolation of typhoid and paratyphoid bacilli
Authors: Tyagaraja Saga
Published: May 2009

A simple modification of Wilson & Blair's medium for the isolation of typhoid and paratyphoid bacilli has been evolved.

1. Instead of the original six ingredients, this modification contains only three, namely, brilliant green, bismuth-ammonium-citrate and sodium sulphite, and may therefore be conveniently termed “B.B.S. medium”.

2. The glucose, sodium phosphate and ferrous sulphate of the original medium are eliminated. The bismuth-ammonium-citrate solution is made without caustic soda.

3. The B.B.S. medium keeps well for several weeks. Deterioration can easily be detected and readily rectified.

4. The inhibitory action towards B. aerogenes is greatly improved in the B.B.S. medium. This is particularly advantageous in countries where this organism is frequently encountered.

5. B. typhosus and B. paratyphosus grow readily. The colonies are sufficiently characteristic and can be picked out early for confirmatory tests.

6. Using B.B.S. medium a complete diagnosis should be possible within 48 hr.
Comparison of the specific mortality rates in town and country districts of Scotland since 1871
Authors: Barclay R. S. , Kermack W. O. , McKendrick A. G.
Published: May 2009

1. An analysis by the “generation mortality” method of the specific mortality rates of the urban and rural areas of Scotland for various calendar periods from 1871 onwards shows that the “diagonal law” previously demonstrated for the population of Scotland as a whole, as well as for certain other European countries, holds for these two subdivisions of the community.

2. Reasons are given for the assumption that the normalized “generation mortality coefficients” (α values) may be taken as a rough measure of the “healthiness” of the environmental conditions which obtained during the childhood of the generation to which they refer. This affords a basis for the comparison of the “healthiness” of the environment of town and country at different periods in the past.

3. Whereas in the earlier half of the nineteenth century the ratio of the α values of country to town was in the neighbourhood of 0·6, indicating that the health conditions in the country might be said to be almost twice as good as in the towns, in 1931 it had risen to almost unity, showing that by that time the town had almost if not quite made up on the country. During this period both town and country conditions showed remarkable improvements, which are reflected in falls of the respective α (× 1000) values in the country from about 12 and in the town from over 20 in 1841, to a common level of about 4·7 in 1931.

4. The essential vagueness of the conception of the “healthiness” of an environment is emphasized. It is consequently necessary not to attach too great importance to the estimate of the date, but the figures given in Table 5 confirm the conclusion that, as regards “healthiness”, between 1930 and 1935 conditions in town and country had become nearly equal.
Porosity of, and bacterial invasion through, the shell of the hen's egg
Authors: Haines R. B. , Moran T.
Published: May 2009

1. Histological methods show four layers in the intact shell of the hen's egg, namely, cuticle, spongy layer, mammillary layer, and inner shell membrane. Distinct channels or pores may be found in the spongy layer, but these tend to disappear in the mammillary layer in which only a network of much finer channels can be observed.

2. Viscometric measurements of the passage of water and air through the shell show that

(a) shells vary widely in their porosity, even when taken on successive days from the same hen;

(b) there is no correlation between porosity so determined and the number of pores counted by staining methods;

(c) the rate of flow is slower from the interior to the exterior than vice versa, and the pore count by staining methods also less on the inside than on the outside.

3. A rough correlation exists between porosity as determined viscometri-cally and the evaporation of water during storage.

4. If the temperature of the egg is higher than a fluid containing bacteria in which it is immersed, the latter are readily drawn through the shell by simple suction as the egg cools down, a point of great significance in the washing of eggs.
Bismuth sulphite media for the isolation of V. cholerae
Authors: Wilson W. James , Reilly L. V.
Published: May 2009

1. A fluid enrichment medium containing sulphite and bismuth based on Read's modification of one of Wilson & Blair's media has been devised and the claims of Read (1939) and Seal (1939) as to the value of such a medium has been confirmed.

2. A saccharose mannitol sulphite bismuth alcohol phenol red agar medium is described and has been found to allow rich growth of the true cholera vibrio and to inhibit the growth not only of B. coli and B. lactis aërogenes but of many vibrios liable to be mistaken for the true vibrio cholerae.

3. Thirty-one strains of true cholera vibrios, obtained from the National Collection, grew rapidly and profusely in the media.

4. Of twenty-five cholera-like and para-cholera strains six grew well, whilst the growth of nineteen was scanty or nil.

5. Of eleven El Tor vibrios five grew in both fluid and solid bismuth media, five grew only on the solid medium and in one no growth occurred in either medium. The El Tor colonies were much smaller than those of the epidemic cholera strains.
Vaccination with live type 4 adenovirus: evaluation of antibody response and protective efficacy
Authors: Van Der Veen J. , Abarbanel M. F. W. , Oei Kiem Giok
Published: May 2009

Live type 4 adenovirus contained in enteric-coated tablets was given to 2628 military recruits. In two trials, the enteric adenovirus vaccine reduced febrile and afebrile adenovirus illness by about 90% or more. Moreover, a decided protective effect against subclinical adenovirus infection as evidenced by seroconversion was found.

The antibody-stimulating effect of enteric adenovirus vaccine was not an adequate measure of its protective capacity. The neutralizing antibody response of recruits given vaccine was poor in comparison with the antibody response to naturally acquired infection with type 4 adenovirus. The latter response was related to the severity of infection.

We are indebted to Colonel Dr B. J. W. Beunders, Head of the Division of Preventive Medicine of the Royal Netherlands Army, for granting us facilities to conduct this study and to Misses W. T. C. J. Smulders, E. M. J. C. Vallas, J. E. M. Dusseldorp and M. M. J. P. Keeris for their valuable technical assistance.
The estimation of carrier rate from amoebic surveys
Authors: Robinson J.
Published: May 2009

The purpose of surveys of amoebae or other organisms is the estimation of the carrier rate in a population, that is, of the proportion of persons who carry a given parasite. As a rule, the tests do not infallibly detect the presence of the organism in a known carrier. Thus simple estimation from a single examination of each member of a sample is not applicable.
Bacteriological aspects of air-conditioning plants
Authors: Whyte W.
Published: May 2009

An investigation was carried out into the bacteriological performance of three air-conditioning plants in a hospital ward. Two of these plants had the facility for recirculating part of the ward air.

An equation has been derived comparing the concentration of bacteria which would be expected to be given off by the humidifiers in the ventilation system, with the concentration of bacteria in the recirculatory tank. The bacterial particles given off by these humidifiers were of nuclei droplet size, and were found to penetrate the filters used with a fair degree of ease. Although the number of bacteria in the humidifier water remained insignificant with a constant overflow of water into the recirculatory tank, on one occasion a build-up of bacteria was demonstrated when the overflow ceased. For hospital use humidifiers of a non-recirculatory type should be used.

The concentration of bacteria on the surface of the recirculatory ducts was assessed, as also were those on the surface of the supply ducts under full fresh air and recirculation. The concentration of bacteria in the supply ducts was low and the use of terminal filters was not merited, although care should be taken to prevent the build-up of bacteria in inlet grills and diffusers. The bacterial concentration in the exhaust ducts was found to be quite high. It was therefore thought that in critical areas, where the ventilation plant may be shut off, the use of some device to prevent reversed air flow may be necessary.

The count of various types of micro-organisms in the fresh air and two-thirds recirculated air are given along with their size distribution. The results of the effect of filtration on the concentration of bacterial particles throughout the air-conditioning plant is given under full fresh air and recirculation. These concentrations appear quite satisfactory. It was found that one set of filters had been overgrown by mould because of free water being brought over from the humidifier. Measures have been suggested to overcome this. When primary or prefinal filtration was approximately 90% efficient to Aloxite 50 (B.S. 2831 Test Dust no. 2) it was demonstrated that a fair approximation to the final filtration figure could be obtained by reference to the quoted efficiency of the final filter to Aloxite 50. After similar primary filtration it was demonstrated that the final filtration of filters against recirculated and fresh air was approximately the same. Owing to the higher number ofStaph. aureusin recirculated air, higher efficiency filtration may be required.

Standards of filtration efficiency for critical and non-critical zones are suggested.
Attempts to recoverMycoplasma suipneumoniaefrom experimental and natural cases of enzootic pneumonia in pigs
Authors: Goodwin R. F. W. , Pomeroy Annette P. , Whittlestone P.
Published: May 2009

Two strains of enzootic pneumonia, which are regularly free from mycoplasmas other thanMycoplasma suipneumoniae, were transmitted experimentally to a total of 22 pigs.M. suipneumoniaewas recovered in liquid medium from the lung lesions in 20 of these animals (91%).

Twelve field outbreaks of enzootic pneumonia were likewise examined forM. suipneumoniae: from each outbreak, cases were selected where many mycoplasmas with the morphology ofM. suipneumoniaewere seen in touch preparations made from the lung lesions.M. suipneumoniaewas recovered from only two of these outbreaks, butM. hyorhiniswas obtained from nine of them.

To establish whether the outbreaks yielding onlyM. hyorhiniswere indeed enzootic pneumonia, material from five of them was used in disease-transmission experiments: enzootic pneumonia was induced in every instance, andM. suipneumoniaewas recovered from three of the five transmitted strains.

It is concluded thatM. hyorhinisis commonly present in the lung lesions of enzootic pneumonia and that this mycoplasma may often prevent the isolation ofM. suipneumoniae. The problem of recoveringM. suipneumoniaein this situation is made more difficult by the fact that in no instance whereM. suipneumoniaewas isolated directly in liquid medium was it cultured in parallel on solid medium.
An alternative method of phage-typingStaphylococcus aureus
Authors: Pether J. V. S.
Published: May 2009

As many cultures ofStaph. aureusuntypable by the international basic-set phages at RTD were typed by a block of 20 extra phages at RTD as by the basic set at RTD × 1000. Reproducibility of the lytic patterns was as good with the extra phages at RTD as with the basic-set phages at RTD, and better than with the basic-set phages at RTD × 1000.

A method of assessing redundancy in any set of phages is presented, and a ‘3-strong differences’ rule is suggested for discriminating between cultures of staphylococci from patterns of phage lysis by the combined set of phages at RTD.

Experience with the combined set of phages suggests that it may be possible to improve the phage-typing of staphylococci by substituting a larger series of phages used only at RTD, for the present set of 22 phages used at RTD and RTD × 1000.
Investigation and treatment of floors of patients' rooms: a study with an agar cylinder
Authors: Kuipers J. S.
Published: May 2009

A cylinder filled with medium is described, with which prints are made of floors or other surfaces. After a print has been made a slice is cut off the medium, put in a Petri dish and incubated. With one filled cylinder about twenty prints can be made. The method can be used for quantitative bacteriological testing of floors, and the effect of treatment with disinfectants can also be checked in a simple way. Preference was given to disinfection with Halamid.