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

We are grateful to Dr C. M. P. Bradstreet who made available some of the rabbit antisera.

1. Faeces from apparently healthy Bantu school children of a periurban district of Johannesburg were examined eight times at regular intervals over a period of 1 year.

2. Of 75 children, 29·3 % experienced at least one salmonella infection and 2·7 % one shigella infection. It is suggested that over a year nearly all children will have one, and many of them several, infections with these pathogens. The infections occurred at a low rate throughout the year.

3. In most cases the infections were asymptomatic. A few of the children showed evidence of being salmonella carriers of long standing.

4. Eighteen different salmonella types were recovered. Salmonella typhi, S. paratyphi B and S. paratyphi C were absent. The organisms were highly resistant to penicillin, erythromycin and novobiocin and a few strains were also resistant to chloramphenicol and tetracycline.

5. The drinking water was of poor quality and may well be implicated in the transmission of the infections.

Our thanks are due to the Director of this Institute, Dr J. H. S. Gear, for permission to publish this paper; to Mr R. G. Robinson for assessing the microorganisms'sensitivity to antibiotics; and to the South African Council of Scientific and Industrial Research, Pretoria, for a grant enabling us to meet the transport expenses.

1. An investigation of measles was made in Nigeria as part of a longitudinal study of 405 village children, supplemented by observations on 1,283 children admitted to a Mission Hospital with the disease.

2. Measles was found to be the most serious of the acute infectious diseases of Nigerian children. During the Imesi village study measles played a major part in the death of 15, or 7% of the 222 children who were seen with measles. The overall case mortality in Nigeria is believed to be in the region of 5%. For children admitted to hospital with the complications of measles, a mortality in excess of 20% is not infrequent. This contrasts with the present situation in Northern Europe and America, where measles is of relatively minor public health importance.

3. Bronchopneumonia was present in nearly half the children needing admission to hospital. Of those with bronchopneumonia, 28% died.

4. Diarrhoea occurred in all stages of the disease, but was most common and severe during and following the period of desquamation. Treatment by parenteral fluid to combat dehydration was required in 55% of children admitted with this complication.

5. Extensive loss of weight was associated with the disease in the majority of children. In the village study nearly one child in four lost 10% of his former weight. The mean time taken to recover former weight was 7·2 weeks.

6. Children frequently developed marasmus and kwashiorkor after an attack of measles.

7. Striking appearances were observed in the rash and subsequently in the skin. In some children the rash darkened in colour in the manner described by Rhazes and other early writers. Extensive desquamation often appeared after the rash. The desquamation was most severe when the rash darkened.

8. The picture of measles in this study resembles descriptions of the disease to be found in the older literature. Accounts of the incidence and severity of bronchopneumonia, laryngitis, diarrhoea and weight loss before 1920 are presented to illustrate this similarity.

9. Possible reasons for differences in the frequency and severity of measles in different places and epochs are discussed. Differences in strains of the virus and host immunity seem unlikely factors, but liability to secondary infections may be of some importance. It is concluded that the severity of the disease is related to the manifestations of the rash. A dark rash, followed by profuse desquamation, is associated with equivalent changes in the larynx, bronchus, and intestines, which are likely to be responsible for the occurrence of bronchopneumonia, laryngitis and diarrhoea. Defective nutrition is a possible cause of the ‘vulnerability’ of the epithelium.

The analysis of the data from Nigeria was made possible by the payment of expenses to Dr Morley by the London School of Hygiene and Tropical Medicine from July 1960 to December 1961. Subsequently the work was supported by a grant from the Medical Research Council to Prof. B. S. Platt, Head of the Department of Human Nutrition, London School of Hygiene and Tropical Medicine.

The authors wish to thank Dr W. R. Aykroyd, Senior Lecturer, Department of Human Nutrition, for his encouragement and assistance in preparing the text, and Miss Allen and Miss Wise for secretarial help. They must also thank Professor Court of the Department of Child Health in the University of Durham for helpful criticism.

1. Salmonella typhi, strain Ty2, grown in vivo and employed as acetone-dried vaccine possessed a higher immunizing potency than the descendants of the same parent strain grown in vitro and employed as vaccine.

2. When 2 × 108in vitro-grown bacteria were employed as challenge, the immunizing effects of both types of vaccine were more marked than after administration of 2 × 108in vivo-grown bacteria as challenge.

3. The higher potency of the in vivo-grown vaccine was apparent in all experiments, whether the challenge strain was grown in vivo or in vitro.

4. Immunogenic substances were isolated from infected organs of mice and guinea-pigs, and an immunogenic substance from the peritoneal fluid of the infected guinea-pigs was concentrated by precipitation with ethanol.

1. The severity of measles in infants and young children in Ilesha in Nigeria suggested this as a suitable centre for a trial of measles vaccine.

2. The trial was divided into three stages. In the first the vaccine was given to a group of 26 children who could be kept under close observation and were seen twice daily. In the second the vaccine was given to 120 children, a similar group receiving gamma globulin and an inert material. In the third stage the effect of vaccine and gamma globulin given as separate injections to 378 children, was compared with that of gamma globulin and inert material given to another control group. The second and third stages were run on the ‘double blind’ principle.

3. The children receiving vaccine alone showed fairly severe reactions but none were disabled by them; for example, 19 % had fever over 103° F. The reactions were similar to those observed in American children, with the one exception that diarrhoea was seen amongst African children receiving vaccine without gamma globulin. Those receiving vaccine and gamma globulin had only minor reactions. In the vaccinated children there was a notable absence of the severe complications seen with the natural disease in Nigeria.

4. Children who were well below the average weight for their age and sex in this community did not show more severe reactions than those above the average weight.

The virulence of Pseudomonas aeruginosa appears to depend on both its ability to grow in the serum of animals and its ability to produce various types of extra-cellular toxins. No strain of Ps. aeruginosa lacking either of these qualifications was ever found to be virulent to animals.

The ability of various sera of animals to inhibit growth of Ps. aeruginosa appears to depend largely on their content of specific antibodies to each serological type of the surface antigens (the slime layer) and, therefore, susceptibility of animals to the infections of Ps. aeruginosa, even within one species, varies considerably from one individual to another.

This work was supported by a research career development award of the U.S. Public Health Service to the senior author (GM-K3–15).

To compare the effects of subcutaneous and intradermal methods of administration of TAB vaccine for primary immunization against enteric infections an investigation was carried out on 257 Army recruits.

The general and local reactions were more unfavourable by the intradermal method. The agglutinin responses were better with the intradermal route.

1. Approximately 1000 Nigerian children between the age of 6 months and 2 years were given Enders ‘B’ meásles vaccine, combined with gamma globulin in all except 120 children. A control group of similar numbers received gamma globulin alone plus inert material.

2. In a preliminary village study the 26 vaccinated children remained free of measles, 19 of the 27 control children developed measles and 2 of these children died.

3. In a blind study among children attending the large child out-patient clinic at the Ilesha hospital, a follow up was also attempted but was more difficult. In all, 272 cases of ‘measles-like’ illness were seen, 192 in control children, and 80 in the vaccinated group. The number in the vaccinated group is believed to be a reflexion of the difficulties under which this diagnosis was made, rather than a failure of the vaccine to immunize. Eleven children are known to have died from measles. All these 11 were in the control group who had not had vaccine.

4. The control children showed a smaller mean gain in weight than the vaccinated in the months following inoculation. The difference may have been due to poor weight-gain among the control children who developed measles.

This work was supported in part by the Health Research Council of the City of New York under contract U 1056 and by the office of the Surgeon General, Department of the U.S. Army, sponsored by the Commission on Viral Infection Armed Forces Epidemiological Board. We wish to thank Dr W. J. Martin, Ph.D., D.Sc. and Miss I. Allen of the Medical Research Council's Statistical Unit for Statistical help.

The vaccines and gamma globulin were supplied by Dr Maurice Hilleman, Director, Merck Institute for Therapeutic Research.

1. Laboratory rabbits were infected with seventeen different preparations of myxoma virus (this probably represents thirteen strains of which four could be classified as fully virulent and the rest as attenuated, two being markedly so).

2. One hundred and twenty-four wild rabbit carcasses were obtained from a rabbit infestation in the throes of an outbreak of myxomatosis.

3. All the carcasses were examined for the presence or absence of myxoma antigens and antibodies by a modified Ouchterlony gel-diffusion precipition test.

4. As a result of (3), we have concluded that the gel test can provide confirmation of the presence or absence of myxomatosis. It is particularly useful in cases of doubt about the clinical diagnosis. The test can also give a reasonable indication of the number of recovered rabbits in a population and, more important still, it can give an indication of the recovery rate during an outbreak of disease. However, attempts to differentiate between fully virulent and attenuated strains of virus were unsuccessful.

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

We are most grateful to Glaxo Laboratories Ltd. for the supplies of monkey kidney cells used in this investigation.

1. A retrospective survey has been made to determine the amount of cross-infection caused by Staphylococcus aureus of one particular phage-type, 83 A, in four main hospitals of a provincial hospitals group, over a period of 2½ years.

2. The total number of strains considered was 1131. Of these, 776 were resistant to tetracycline and therefore the most likely to be of significance in cross-infection. Of these 776 strains, about one-third belonged to phage-type 83 A. In the hospital where 83 A strains were most prevalent, they formed about one-half of the tetra cycline-resistant strains; in that where they were least prevalent, about one- quarter.

The clinical sources of the tetracycline-resistant strains are described.

3. It was found that type 83 A strains were the most likely to show resistance to erythromycin, chloramphenicol or novobiocin.

Of a series of 214 type 83 A strains sensitivity tested against methicillin, using a disk-plate method, none was found to be resistant.

My thanks are due to Prof. R. E. O. Williams, St Mary' Hospital Medical School, for his helpful criticism of this paper and, in his previous capacity as Director of the Staphylococcus Reference Laboratory, Central Public Health Laboratory, Colindale, to him and his staff for supplying me with typing phages, and instructing me in their use. I should also like to thank Dr M. T. Parker, Director of the Cross Infection Reference Laboratory, Colindale, for a continued supply of these phages; the Hon. the Viscount Waverley, F.R.C.P., for allowing me to quote from the case history of a patient under his care; and Mr K. Allen, F.I.M.L.T., and other members of my technical staff for their assistance.

During attempts at purification of horse-sickness virus for electron-microscopy from infected mouse brain extracts, it was found that a combination of polyethylene glycol precipitation of the virus, ultracentrifugation and zone electrophoresis gave promising results. The final purified material could not be regarded as pure on account of the presence of considerable normal brain components, but it contained particles not present in normal brain treated identically, which could be recognized as virus particles. The virus particles appear to have diameters of 70–80 mμ and are estimated to have 92 rod-shaped subunits radiating from a spherical body.

The authors wish to express their gratitude to Prof. A. Kipps and R. A. Alexander for their continued interest in this work.

The electron micrographs were taken by Mr L. G. Fowle of the Department of Physics, University of Cape Town.

This investigation was supported in part by a Public Health Service research grant AI 04044–02 from the National Institutes of Health, Bethesda, U.S.A.

The levels of neutralizing antibody against several adenovirus serotypes were determined on 42 paired specimens of maternal and cord serum and on 197 single serum specimens from children up to the age of 8 years.

The antibody distribution indicates that adenovirus infection is endemic in Sheffield just as it has been shown to be endemic in Cleveland and Washington.

We should like to thank Prof. C. P. Beattie for his advice and criticism, Dr C. C. Bowley of the Sheffield Regional Blood Transfusion Centre for paired maternal and cord sera, Dr M. H. Hambling for the provision of adenovirus stock strains and Mr Foster, medical artist, for preparation of the figures.

By using a specially designed apparatus it was possible to study the yield of airborne organisms when various hospital textiles, artificially and naturally contaminated, were shaken under reproducible conditions. The results indicated that contaminant organisms are most effectively liberated when a textile is shaken in contact with a second fabric. The yield of airborne organisms was approximately doubled under the conditions used. Similarly, a 95 % removal of surface con taminants was also demonstrated by shaking in contact with a second textile, compared to 52 % removal when the textile was shaken alone.

These findings confirm those described in an earlier study of the spread of air borne organisms in a ward environment. It is suggested that this increase in aerial spread of infectious particles, previously referred to as a ‘counterpane effect’, is due to friction between the contaminated textile and its covering material.

Other points which emerged in the course of this work were the demonstration that cotton blankets tended to yield higher airborne counts than woollen ones and that the size distribution of bacterial particles dispersed by textiles is the same as that of the particles which contaminate the textiles.

It is with pleasure that we acknowledge the encouragement and advice of Prof. Walsh McDermott, in whose Department at the Cornell Medical College, New York, this work was carried out. We are also grateful to the National Institutes of Health, Bethesda, for financial support under Grant No. E-635(C 7).