Fifty-six cases examined for Dysentery bacilli. All save one were clinically dysentery, and all save two were negative for amoebae and other protozoa.

Twenty cases (35·7%) yielded dysentery-like bacilli.

From these twenty cases thirty-six organisms were isolated and studied. Of these—

Six corresponded with no familiar pathogenic organism.

Six resembled B. Shiga. Two agreed completely both by fermentation and agglutination. One also gave typical fermentation and agglutination results but was at first a motile organism, although in later generations it became non-motile. The other three are less definitely Shiga bacilli.

Five were mannite-fermenting organisms but only one agreed very closely in its fermentation reactions with B. Flexner and it was not agglutinated by Flexner serum.

Sixteen cultures from ten separate cases corresponded closely with Morgan's bacillus.

Eight of these agreed completely in their characters with Morgan's No. 1 bacillus.

Three differed only from Morgan's No. 1 in being non-motile.

Five presented characters intermediate between those of Morgan's No. 1 and Bowman's “Bac. S.”

Of six cases yielding Morgan's bacillus, agglutination with the patient's own serum was positive in five.

Three cultures showed affinities with the Bac. enteritidis.

Polyvalent anti-dysenteric serum treatment tried on a considerable number of cases was a complete failure.

The following conclusions appear to us to be justified as a result of the experiments cited above:—

(1) Close contact of plague-infected animals with healthy animals, if fleas are excluded, does not give rise to an epizootic among the latter. As the go-downs were never cleaned out, close contact includes contact with faeces and urine of infected animals, and contact with, and eating of food contaminated with, faeces and urine of infected animals, as well as with pus from open plague ulcers. This conclusion is justified from Experiments I and II and especially from Experiment VI, in which close contact with infected animals was maintained for nearly a month. In Experiment I the animals were inoculated cutaneously, and in many cases had developed ulcers at the site of inoculation.

(2) Close contact of young, even when suckled by plague-infected mothers, did not give the disease to the former.

(3) If fleas are present, then the epizootic, once started, spreads from animal to animal, the rate of progress being in direct proportion to the number of fleas present. Thus, in the experiments during the months of December, January and February, the epizootic was very rapid in those go-downs, namely, Nos. 1 and 2, Experiments IV and V, in which the flea population was abundant and was kept up by a natural supply from the roof: it was much slower in Experiment VII, go-down No. 5, in which the flea supply was kept up artificially; and, finally, it was slowest of all in go-down No. 6, Experiment VI, in which there was no definite natural supply of fleas, and from which the fleas were daily removed for a period of six days, after which removal only a comparatively small number could be caught.

(4) An epizootic of plague may start without direct contact of healthy animal and infected animal. Thus, in the case of Experiment V in go-down No. 1 the healthy guinea-pigs were not put in until the last inoculated guinea-pig had died and been removed.

(5) We have in Part II shown by direct experiment that the rat flea can convey plague from rat to rat. Further experiments (Experiments VI, VII and XI) of a similar nature with the fleas removed from infected go-downs are now recorded.

(6) Infection can take place without any contact with contaminated soil. Thus in go-downs Nos. 1 and 2 (Experiments VIII, IX), guinea-pigs placed in wire cages two inches above the ground developed plague; also the monkey in go-down No. 2 (Experiment XIII) was never in contact with the ground.

(7) Aerial infection is excluded. Thus, guinea-pigs suspended in a cage two feet above the ground did not contract the disease, while in the same go-down those animals allowed to run about and those placed two inches above the floor became infected. Further, the monkey surrounded by tangle-foot was exposed as much to aerial infection as the control animal which contracted the disease.

1. The red blood corpuscles of different species have definite and distinct mean lytic points.

2. The apparent tonicity of sheep serum has no relation to the mean lytic point of the red corpuscles of that individual.

3. The apparent tonicity of sheep serum is not due to its proteins but to its lipoids.

4. The residue of sheep serum, after removal of proteins and lipoids, is sufficiently alkaline to cause lysis.

1. Recovery of a strain of Brucella abortus Bang from a foetus aborted by a cow in Mauritius is reported.

2. Agglutination tests performed on samples of blood from cows of the Government Dairy indicate that contagious abortion of cattle is present in this country; approximately 24% of the animals from the Government Dairy belonged to the latent or past infection group; 18 % to the active infection group and 15% were presumptive bacilli excreters.

3. As aresult of agglutination tests with the blood serum from man Undulant fever due to Br. abortus is suspected to occur in Mauritius.

In the present paper an attempt has been made to devise a method of determining mortality rates at ages from causes of death associated with childbearing. The sources of possible fallacy in this procedure have been discussed, and it is probable that the results found will represent fairly accurately the true course of mortality in this country.

From all causes of death in childbearing, mortality follows this course: beginning with a high value in the age group 15–20, the rate drops to a minimum in the second quinquennium of reproductive life and thereafter gradually increases with age.

The main components of the death rate exhibit a similar age distribution, but other less important causes of death show an uninterrupted increase with age from the commencement of the reproductive period.

Eclampsia is much more common in young women, but this may be entirely due to the greater proportion of primiparae at these young ages. Estimated in terms of first births the death rate increases rapidly and steadily with age, subject to a small exception in the first quinquennium which may possibly be a consequence of unfavourable marital selection at that age.

The high puerperal mortality of young mothers cannot wholly be accounted for by the excessive dangers of primiparity. Evidence has, however, been submitted that these young women are, on the average, a less healthy sample of the total female population at that age and that, apart from primiparity and adverse selection, the death rate from childbed causes probably follows the same law of mortality as of women in general from all other causes of death.

There has been within recent years a decline of nearly 50 per cent, in the puerperal mortality in young mothers of 15–20 and a smaller decrease in the second quinquennium of reproductive life; but there is no evidence of any improvement at later ages. These phenomena have been brought into relation with the change which has taken place in the death rate from all other causes in married women at these ages. The youngest group of married women, relative to unmarried of the same age, were in the more recent period studied in a much more favourable position with regard to their mortality from causes other than those connected with childbearing than they had been formerly. No corresponding improvement has taken place in the relative mortalities from all other causes in older women within the childbearing ages.

These results suggest that the general health of the mother is a factor of great importance in determining the height of the mortality rate in pregnancy.

1. The problem of louse control by powders has been shown to be twofold, namely (a) to kill the lice present on a verminous person at the time of treatment, and (b) to prevent reinfestation of a deloused person or infestation of a clean person. In these experiments no single insecticide was found that would fulfil both functions.

2. The work shows the necessity of using laboratory tests (‘cell tests’) in conjunction with insecticide tests on the parasite living under natural conditions (‘field trials’).

3. The technique and results of the cell tests and the field trials are described in detail. In the field trials naturally louse-infested persons living in verminous surroundings were treated and examined daily to observe the true insecticidal value of each preparation.

4. Naphthalene was found to be the most effective insecticide for killing body lice quickly. It failed to give any protection against reinfestation.

5. The vegetable insecticides, derris and pyrethrum, were found to be toxic to Pediculns humanus corporis, but either alone or in combination with each other they were inferior to other combinations of insecticides.

6. The combination of high-boiling tar acids and derris resulted in the combined chemicals being more toxic to lice than either alone. This proved an activation effect, and the theory of activation is discussed.

7. Activated derris, while slow in killing lice, was shown to be the best preparation which gave protection against reinfestation.

8. The preparation referred to as A.L. 63 was outstanding as the best preparation that controlled body lice and which fulfilled the original conditions stipulated for a successful louse powder for human use. The formula is:

H.B.T.A. 2 %

Derris root 14·3 % giving 1 % rotenone and a minimum of 3 % extract in the final product

Naphthalene 50·0 %

China clay 33·7 %

The nature of each chemical in this formula is defined.

9. A.L. 63, when applied to the clothing of a verminous person, killed 95% of all lice on the treated garment in 24 hr., and gave complete protection against reinfestation for an average of 5 days, and partial protection for 8 days. When applied to clean garments as a prophylactic measure, A.L. 63 gave complete protection for an average of 7…8 days, and partial protection for approximately 16 days.

10. Patients living in a verminous environment were made to wear one shirt continuously for a month without washing it. Even under these conditions they were protected from infestation by treatment of the inside of the shirt, at 8-day intervals, with A.L. 63.

11. A short history is given of the use of A.L. 63 in the British army from 1940 to 1944.

During this work we have had much help and sympathy from many people, but we would like to place on record our especial thanks to the following: Prof. P. A. Buxton, of the London School of Hygiene and Tropical Medicine, for supplying us with the original material for establishing a louse colony, and for his great interest and encouragement during the work; Dr W. E. Parry, the Divisional Police Surgeon at Spitalfields, for his kindness in describing the best areas to search for suitable patients, and his assistance in finding suitable accommodation for establishing the ‘clinic’; those numerous volunteers, within the Cooper, McDougall and Robertson organization, who offered to feed lice when the colony was being maintained at the Research Station, and suffered much discomfort while doing so.

This study aimed to understand the population and contact tracer uptake of the quick response (QR)-code-based function of the New Zealand COVID Tracer App (NZCTA) used for digital contact tracing (DCT). We used a retrospective cohort of all COVID-19 cases between August 2020 and February 2022. Cases of Asian and other ethnicities were 2.6 times (adjusted relative risk (aRR) 2.58, 99 per cent confidence interval (95% CI) 2.18, 3.05) and 1.8 times (aRR 1.81, 95% CI 1.58, 2.06) more likely than Māori cases to generate a token during the Delta period, and this persisted during the Omicron period. Contact tracing organization also influenced location token generation with cases handled by National Case Investigation Service (NCIS) staff being 2.03 (95% CI 1.79, 2.30) times more likely to generate a token than cases managed by clinical staff at local Public Health Units (PHUs). Public uptake and participation in the location-based system independent of contact tracer uptake were estimated at 45%. The positive predictive value (PPV) of the QR code system was estimated to be close to nil for detecting close contacts but close to 100% for detecting casual contacts. Our paper shows that the QR-code-based function of the NZCTA likely made a negligible impact on the COVID-19 response in New Zealand (NZ) in relation to isolating potential close contacts of cases but likely was effective at identifying and notifying casual contacts.

A total of 637 strains of Salmonella bareilly received from different parts of India between 1959 and 1985 were phage typed using five locally isolated wild phages. The overall typability was 94·5% and 11 different phagc types could be defined. Phago types 10 and 1 were the most prevalent and the geographical and source distribution is described.

1. Numerical counts on gelatin media are of very limited value for surface well examinations and are quite useless for open draw-wells. The blood-heat enumeration is of use, but still of but limited value.

2. The influence of rainfall and local conditions generally is marked for this class of waters with regard to their bacterial content.

Whether the well is uncovered, or covered and provided with a pump has a very important influence upon the bacteriological results. For a good many wells which show very bad bacteriological findings the cause of pollution is frequently due to surface pollution rather than to pollution of the ground water through the soil. If these wells are properly protected they will become suitable sources of drinking supply.

3. The results obtained confirm the value of B. coli and streptococci estimations as the best tests by which to judge the freedom from pollution of such waters.

The streptococci results are of great value, only second in importance to the B. coli determinations. In numerical distribution these two organisms closely agree. The presence of streptococci is more reliable as evidence to deduce pollution than their absence is to exclude it.

4. An opinion regarding the freedom of surface wells from pollution is best formed on the basis of combined topographical and bacteriological investigation.

5. Inspection alone is frequently quite insufficient for the purpose of determining if a well is contaminated and if it should be closed.

Of the 50 wells examined no less than 31 had to be classed as doubtful (Series C), topographical examination alone affording insufficient data for the expression of a decided opinion.

In view of the fact that pure water supplies are not easy to obtain in many rural districts, a water supply, which may have been in use for many years, cannot be condemned in the absence of clear evidence that it is unsatisfactory and dangerous.

6. In surface well waters a large proportion of the coli-like organisms isolated are atypical in one or more particulars.

7. Typical B. coli implanted into soil showed some alteration of character, but the changes were not extensive and no evidence was obtained that the widely aberrant organisms met with in different soils and waters ever represent typical B. coli altered by unfavourable environment.

8. Organisms closely allied to B. coli, but differing in one or more characters, possess significance as indicators of faecal contamination.

The more nearly the organism isolated resembles an “excretal” B. coli the greater is its significance as an indicator of pollution. Consequently the fewer the number required to condemn a sample water in which they occur. Stated as a working proposition, the more the characters of the coli-like organisms deviate from that which for convenience may be spoken of as the typical form, the greater the proportionate number of them required to condemn the water.

9. The presence of ‘excretal’ B. coli in 10 c.c. or less of a surface well water points to undesirable pollution and is sufficient to condemn the water.

The Japanese quarantine system monitors incoming passengers to detect imported pathogens at international airports. At one airport, we found that 74% of 13315 travellers returning with diarrhoea had visited only one country before entering Japan. On the basis of our results, we hypothesized that the international distribution and potential source of bacterial strains could be inferred by analysing strains isolated from travellers returning to Japan. In order to demonstrate the potential for this system, we randomly selected five Shigella sonnei strains and examined their restriction fragment length polymorphism patterns. One set of strains appeared to be closely related, while three sets, isolated from travellers who visited different countries were possibly related. These results suggest that international distributions and potential sources of S. sonnei may be inferred by monitoring isolates from passengers arriving at a Japanese quarantine station.

It has long been recognized that there is a relationship between environment and health and examples of this association are easy to cite—overcrowding tends to spread infection. But our knowledge of the exact part played by occupational as distinct from economic and social environment is as yet imperfect.' The liability of the worker to ill-health, apart from any inborn constitutional weakness, is determined broadly by two factors. The first is the influence of the type of work directly upon the worker, an influence inherent in the actual occupation and the conditions under which the work is done. This might be regarded as the direct occupational risk. The second is the economic and social environment conditioned by the occupation followed: this might be termed the indirect occupational risk. This distinction was recognized by the Eegistrar-General who stated that both factors are essentially components of the total occupational risk since ' If a man is obliged by his place of work and his rate of pay to live in an insanitary area, the extra risk of death involved is, in a wider but very real sense, part of the occupational risk'. The purpose of the present paper is to try to disentangle the parts played by each in determining the occupational mortality from a specific disease like tuberculosis. The difficulty which previously presented itself was the absence of a standard which could be regarded as a measurement of the indirect occupational risks. The Registrar-General, in his last Occupational Mortality Supple-ment, has provided an approximate index, by publishing data on the mortality of males following particular occupations and also that of their wives. His viewpoint was.'. for no trade could longer be regarded as directly prejudicial to health if it were found to entail as much excess risk for the wife as for the husband. In such a case excess mortality would evidently be in the main attributable to the social conditions implied.' Greenwood likewise stated that ‘the wives share the social and geographical advantages of their husbands’ occupation but, with relatively ummportant exceptions, are not exposed to their specific occupational risks’. The purpose of the present paper is to try to disentangle the parts played by each in determining the occupational mortality from a specific disease like tuberculosis. The difficulty which previously presented itself was the absence of a standard which could be regarded as a measurement of the indirect occupational risks. The Registrar-General, in his last Occupational Mortality Supplement, has provided an approximate index, by publishing data on the mortality of males following particular occupations and also that of their wives. His viewpoint was. ‘..for no trade could longer be regarded as directly prejudicial to health if it were found to entail as much excess risk for the wife as for the husband. In such a case excess mortality would evidently be in the main attributable to the social conditions implied.’ Greenwood likewise stated that ‘the wives share the social and geographical advantages of their husbands’ occupation but, with relatively ummportant exceptions, are not exposed to their specific occupational risks'.

A multiple-tube technique based on peptone water incubated at 44 °C for 24 h followed by detection of indole was found to be sensitive and specific for the detection of Escherichia coli in oysters and mussels. The method has the advantage of providing rapid results and is both less expensive and less time-consuming than other MPN techniques.

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.

We aimed to estimate the secondary attack rate of mpox among UK household contacts and determine factors associated with transmission to inform public health management of contacts, during the global outbreak in 2022. Information was collected via NHS and public health services and included age, gender, place of residence, setting, and type of contact. Aggregate information was summarized for the UK. Record level data was combined for England, Wales and Northern Ireland, and multivariable logistic regression was used to determine factors associated with transmission. The secondary attack rate among UK household mpox contacts was 4% (60/1 526). Sexual contact with the index case was associated with a 11-fold increase in adjusted odds of becoming a case in England, Wales, and Northern Ireland (95% CI 5.5–22, p < 0.001). Household contacts outside of London had increased odds compared to London residents (adjusted OR 2.9, 95%CI 1.6–5.4, p < 0.001), while female contacts had reduced odds of becoming a case (aOR: 0.41, 95% CI: 0.15–0.95). We found a low overall secondary attack rate among household mpox contacts with strong evidence of increased transmission risk associated with sexual contact. This evidence will inform the risk assessment of contacts and support prioritization of those with close intimate contact for follow up.

HArris & LEong (1936) found that vitamin B1; adsorbed from urine, could be measured by the rat bradycardia method of assay. The amount of vitamin B1 excreted was found to correspond in general with both the dietary intake and the physiological state of the subjects.

That out breaks of plague are associated with a more or less simultaneous mortality amongst rats is an observation of great antiquity. After the discovery of the bacillus by Yersin and Kitasato this concomitant disease of rats was identified as plague, and during the last twelve years the association of rat plague and human plague has been shown to be almost invariable. The relationship has been so striking that many observers who have studied the question on the spot, e.g. Yersin, Ogata, Simond, Thompson, Koch, Gaffky and many others, have arrived at the opinion that from an epidemiological point of view one must regard plague as essentially a rat-disease in which human beings may participate.

Whether the vaccine virus is filterable or not has been the subject of experiment and discussion for many years and since Negri's results published in 1905, from which he deduced that the virus was filterable, numerous experiments dealing with the subject have been made by many workers.

About 25 years ago Dr J. S. Haldane, Dr A. E. Boycott and Capt. Damant, R.N., in the course of investigations for the British Admiralty, worked out a system of decompression for divers and compressed air workers. This system was adopted by the Admiralty, and by its use compressed air sickness has been practically eliminated entirely amongst naval divers. The system has become known as stage decompression, although in fact stages are not an essential feature of it, though a convenience in practical working. The system has been frequently and fully described. The latest explanation will be found in the last edition, 1935, revised by Haldane and Priestly, of Respiration, by J. S. Haldane (Clarendon Press). Its most essential feature is that the pressure is lowered quickly to approximately half the absolute pressure during decompression, and one of the most important assumptions for working out the decompression tables is that different parts of the body saturate and desaturate at different rates. Enquiries sent out by me during 1934 to the United States, the principal countries of Europe and to Japan indicate, so far as definite information has been received in reply, that stage decompression has been universally adopted for divers, but in no case has it been adopted for caisson and tunnel workers in countries where State regulations already existed, except in a modified form, and I conclude that the reason for this failure to adopt stage decompression is the existence of statutory regulations, either still in force, or only partly modified in accordance with new ideas.

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.