1. The term “reinfection” has been defined as the secondary infection of a scarlet fever patient during hospitalization with Str. pyogenes belonging to a serologically different type from that producing the primary infection.

2. Of forty-seven scarlet fever patients nursed in a multiple-bed ward and swabbed twice weekly during their period of isolation, thirty-three (70.2 per cent) became reinfected with a serological type of Str. pyogenes different from that causing the primary disease.

3. In fifteen out of the thirty-three patients reinfected, the reinfection was “latent”, i.e. gave rise to no clinical signs, while in the remaining eighteen the reinfection was “manifest”, i.e. was accompanied by clinical signs or complications.

4. Patients nursed in cubicles or in a ward confined to infections with a single serological type did not show reinfection; their convalescence was progressive and there were no late complications.

5. The majority of complications occurring during the third week of hospitalization and subsequently, in multiple-bed wards devoted to scarlet fever, are due to reinfection.

6. Most reinfections occur during the third week in hospital at a time when patients are as a rule convalescent from their primary infection.

7. The most frequent mode of transmission of reinfection appears to be by direct contact of patient with patient.

8. Ten instances of “relapse” in scarlet fever (only three in the present series) are quoted; in all of them the patients were nursed in multiple-bed wards. In each instance the “relapse” coincided with the isolation of a fresh serological type of Str. pyogenes from the throat, and must therefore be regarded as a second attack of scarlet fever.

9. The various systems of nursing patients in isolation hospitals are discussed and it is suggested that scarlet fever patients should be cubicle-nursed if possible. Failing this they should be nursed by the bed-isolation method in multiple-bed wards. By setting aside small wards it might be possible to keep together patients who are all infected by the same serological type of Str. pyogenes; the number of such wards would vary with the number (usually three or four) of epidemic types current at the time.

1. The experimental data obtained by Greenwood et al. (1936) relating to epidemics of the virus disease ectromelia in mice have been examined in the light of mathematical theory. Attention has been directed in particular to the life tables calculated from the observed data, which give the chance of survival and death after various periods of cage life.

2. The life table relating to ectromelia 1 during the steady state phase from 1. iii. 32 to 31. viii. 32 shows very close agreement over the range 0–550 days with that predicted by the theoretical equation which involves only four arbitrary constants. A slight discrepancy over the first few days is evidently due to the fact that representation of the death-rate and the recovery rate by constant coefficients does not accommodate an incubation period. The values of the constants obtained from the data give a measure of the essential characteristics of the epidemic.

3. General agreement, though not so complete, is also found when the theory is applied to ectromelia 2 during the priod 1. xi. 31–30. iv. 32. During this phase however, although conditions were otherwise apparently uniform, a steady state had not actually been attained. On the other hand the equations do not apply so satisfactorily to the obviously inhomogeneous period 1. v. 32–20. x. 32.

4. In the present analysis the assumption of constant rates gives a satisfactory account of the progress of an infection in a susceptible community. This result suggests that for many purposes the assumption of constant rates may be adequate.

5. The short period fluctuations observed in the ectromelia epidemic were probably random in character and have no relationship to periodic fluctuations such, for example, as those detected by Brownlee in the case of measles.

The variation in fertility between different sections of the London area has been, and in spite of the decline, still is, considerable. In London as a whole the birth-rate has fallen by 56 per cent since 1870–2, while the potential rate shows a decline of only 6 per cent. The fertility of the boroughs is highly correlated with the index of their social status. A higher birth-rate is recorded in the areas with a large proportion of unskilled or semi-skilled labour, a lower birth-rate in the areas with a high proportion of the professional and more affluent members of society. Other indices of relative poverty and wealth and hygienic conditions give a similar answer. The decline in fertility during the past 20 years is not sensibly related to these indices but appears in its rate to have been broadly equivalent throughout the area.

It was Heraclitus who said of his predecessors that they had much knowledge but no sense, and this criticism often comes to mind when workers pause in retrospect and wonder that the application of the quite adequate knowledge of a generation ago was not applied in a practical and wise manner. Perhaps it may seem that a long time elapsed after compulsory education was adopted before it was realized that a vast number of children were physically quite unfitted to benefit from the learning presented to them; and it was a still longer time before it was hesitatingly acknowledged that the art of living, the teaching of an hygienic way of life, was the most important aspect of education. For without this the benefits of the whole system are of little lasting worth or real utility. Thus it is that open-air education, born late in time, is of such paramount importance; because although ordinarily and primarily conceived for restoring delicate children to health, the main great permanent value of this work is that it teaches in a practical and pleasant manner the greatest of all arts—the art of living.

Crystalline histamine picrate and hydrochloride have been prepared from cotton dust. The melting-points and crystalline structure found are in agreement with those obtained by other workers.

The blood histamines in sixty-five card-room workers have been estimated and compared with the figures found in 103 students and eighteen elderly chronic bronchitics. The figures for the three groups are shown in distribution figures, and the card-room workers have, on an average, a higher blood histamine than both groups of controls. It has, however, to be admitted that the differentiation of card-room asthma from other respiratory diseases on the basis of the level of blood histamine cannot be guaranteed in individuals.

1. An experiment on the feeding of calves is described, which lasted over 2 years, and which was carried out on a healthy Shorthorn herd free from tuberculosis and contagious abortion.

2. Alternate animals as they were born were allocated, without any selection whatever, to one or other of two groups. One of these was fed on raw, the other on pasteurized milk. Every animal received its mother's colostrum for 3 days before being put on the milk diet.

3. The milk used was taken from the mixed morning's milk of the whole herd. It was divided into two parts, one of which was given raw, the other of which was submitted to low-temperature pasteurization at 145° F. (628° C.) for 30 nun, and subsequently cooled. The animals were fed morning and evening on measured quantities that were in strict relationship to their body weight.

4. In addition to the milk, hay was allowed ad lib. Observations showed that practically none was eaten during the first month, after which each animal consumed about 1 lb. a day, rising to 3 lb. by the eighth week.

5. With the exception of two weaklings which died after 15 and 23 days respectively from causes apparently unconnected with the nature of their diet, all the animals—twenty-five in the raw and twenty-three in the pasteurized group—throve well, and showed no obvious signs of rickets or anaemia.

6. The average increase in weight over the 8-week period for the animals in the raw group was 53·72 lb., and in the pasteurized group 53·86 lb., or 61·18 and 62·94 per cent respectively. This practical identity in weight increase is all the more surprising in view of the fact that the number of bull calves was very much less in the pasteurized than in the raw group.

7. The highest individual gain among the bull calves—one of 80 lb.—and the highest individual gain among the heifer calves—one of 63 lb.—both occurred in animals fed on pasteurized milk.

8. At no time throughout the experiment was any observer, lay or professional, able to distinguish between the two groups of animals.

9. The diet given, though permitting of good skeletal development, was insufficient to fatten the animals. After they had been transferred, however, to a normal diet at the conclusion of their 8 weeks in the experiment, they soon put on weight and within 2 or 3 months were indistinguishable in size or condition from animals that had received a more generous diet from birth.

10. There is nothing in these results to suggest that the nutritive value of pasteurized milk for calves is in any way inferior to that of raw milk.

The paper describes a series of observations made in a well-built room in south-west Persia. A study was made of conditions of temperature and humidity in the room, and between the clothes and the body.

Observations were made in the cold and the hot seasons. In spite of the great contrast which prevailed in the room at these two seasons, there was very little difference on the surface of the body.

The observations are consistent with those published by Mellanby, who worked under a wide range of artificially produced climatic conditions.

1. Guinea-pig vaccination experiments have shown that these animals can be rendered completely immune from infection with virulent strains of L. icterohaemorrhagiae when they are treated with non-virulent living vaccines, or formalinized, heat-killed, phenolized, and dettolized suspensions of virulent cultures.

2. Vaccination with homologous strains of L. icterohaemorrliagiae produced better immunity than when heterologous strains such as L. hebdomadis or L. icterohaemorrhagiae Rachmat are employed.

3. Immune bodies are demonstrable in the serum of guinea-pigs vaccinated with L. icterohaemorrhagiae Weil, and a lytic titre of 1/6 appears to indicate that sufficient protective antibodies are present.

4. Following upon vaccination and inoculation with virulent cultures, carrier conditions have developed in animals treated with chemically killed vaccines of L. icterohaemorrhagiae Weil and with living non-virulent suspensions of the heterologous strain L. hebdomadis and L. icterohaemorrhagiae Rachmat.

The Flexner dysentery bacilli are non-flagellated, and their agglutination is determined by somatic antigens situated at the cell surface. So far as the author is aware, phasic variations, of the kind that Andrewes (1922) demonstrated in the flagellar antigens of the bacilli of the typhoid-paratyphoid group, have not yet been observed in the case of 0 antigens; but the variations described above would appear to be of this type. The V, W and Z strains examined gave rise to variants, such as Vb, that had lost, completely or almost completely, the group somatic antigen, or antigens, but showed a consistent tendency to revert to the form in which the group antigens were present.

No evidence could be obtained of variants in which the group antigens were present, while the specific antigen was lacking; but the substrains, such as Va, that showed the presence of both group and specific antigens, appeared to differ from the parent strain in showing no tendency to give rise to variants of the Vb type.

1. A further improvement in the modified McLeod's medium (Gaze, 1933) has resulted from the substitution of saccharose for glucose with the addition of Andrade's indicator.

2. Of the total positive swabs, the saccharose-containing medium detected about 22 per cent which were negative on Loeffler's medium, whereas it failed to detect only 0·36 per cent.

3. On this medium colonies typical of the gravis, intermediate and mitis types are formed and can be easily differentiated with the aid of a hand lens. It is also invaluable for the isolation of pure cultures.

Despite considerable research on the problem of leukaemia, its etiology is still obscure. Endocrine dysfunction, effect of X-ray, trauma and etiological features suggestive of malignant tumours have been advanced as possible causes. The very nature of the disease as well as data on leukaemia in fowls, favour the theory of an infectious origin. Poverty, physical and mental strain, lymphatic constitution, syphilis, malaria and other infectious diseases have been suggested, often on inadequate grounds, as predisposing factors in leukaemia. Interesting results were obtained by MacDowell and Richter on susceptibility of mice to leukaemia.

Arising out of the routine selection of wheat germs for the production of a composite high-value and reasonably uniform mixture, it has been found that the variation in the vitamin B activity of unselected wheat germ is greater than has been generally suspected.

1. Organisms biochemically resembling the metadysentery bacilli of Castellani (1927) or sensu largo B. coli anaerogenes of Lembke (1896) have been recovered locally from the urinary passages of man.

2. These organisms were found in cases of enteric-like fevers, pyelitis and cystitis.

3. Similar to Dudgeon's slow lactose-fermenting bacilli of the urinary tract, they have been shown to possess marked haemolytic action for red blood corpuscles.

4. Serologically, they appear to fall into at least two groups of bacilli.

5. They are believed to be pathogenic.

Evidence has been obtained that where the adsorbing capacity for Vi agglutinins is known to be present it is also possible to show affinity for Vi bacteriophages. However, from the conduct of paratyphoid C strains containing Vi antigen it appears that the presence of Vi antigen causes only the adsorption of Vi bacteriophages, but that in the production of lysis by these bacteriophages other factors play a part.

1. Bight serological types of haemolytic streptococci were recognized in acute scarlatina during the 1933 epidemic in Edinburgh.

2. Five of these types were identical with Griffith's types 1, 2, 3, 4 and 5, while the remainder have been named, provisionally, B, C and D.

3. Type 5 was predominant during the two months preceding the epidemic and throughout the early development of the outbreak.

4. The epidemic was maintained by successive increases in the proportion of cases due to the remaining type, particularly type 3.

5. The age-group incidence in the epidemic year was identical with that of non-epidemic years.

6. 36·8 per cent of patients on discharge were found to have haemolytic streptococci in the throat but in only 5·4 per cent was a large number of organisms isolated.

7. Haemolytic streptococci isolated from discharged convalescents were in the majority of cases of the same type as the admission strain.

By limiting our cultural investigations to persons who possess appreciable quantities of O agglutinins, we have detected a number of typhoid carriers and there are no indications that any carriers have been missed by following this labour-saving procedure. Several of our carriers were found to possess no H agglutinins.

As, however, O agglutinins occur in persons who are not carriers, and the number of such positive O reactors is increasing through the use of vaccines, the number of cultural examinations where no positive results can be expected is growing at a rate which will gradually make our procedure more difficult of application.

It would seem that Vi agglutination might provide a new and efficient method of narrowing down the field for cultural examinations. Vi agglutinins are very rare in normal persons. We have 4 manifest chronic carriers who possess significant quantities of Vi agglutinins. We have 3 persons who at one time were chronic stool carriers, in whom we now also find significant quantities of Vi agglutinins, but in whom at the time we cannot demonstrate typhoid bacilli. We also have 5 persons who at one time were chronic carriers, who now do not show any Vi agglutinins, and in whom we also at this time cannot find typhoid bacilli. Two of these were urinary carriers, which makes their negative cultural results more significant. Lastly, we have 2 persons who at one time obviously were temporary urinary carriers, and who now have lost their bacilli, and in whom also we now cannot detect Vi agglutinins.

In the search for typhoid carriers negative cultural results carry little weight. Our positive findings support the view that typhoid carriers are characterized by the possession of significant quantities of Vi agglutinins.

A comparative examination of the hippocampus and mid-brain in a series of 37 brains from suspected rabid animals has shown the marked superiority of the hippocampus as the site of election for Negri bodies.