The sensitivity of in vitro- and in vivo-grown strains of S. typhi was determined not only by their antigenic structure, but also by their growth phase. An increased vulnerability to the antibody-complement system has been found in cells during the lag and the early exponential phase, while non-multiplying cells devoid of any nutrient were almost invulnerable to the antibody-complement system. Extracts of organs from normal and infected animals may promote the growth of S. typhi, and, therefore, increase its vulnerability to the antibody-complement system. The majority of extracts from organs of mice infected with strain Ty 2 inhibited markedly the bactericidal action of serum on this strain and, to a lower extent, on strain O 901.

1. A technique for measuring the antibacterial activity of germicides on pig skin in micro-respirometers has been described.

2. Using this technique the activity of the following germicides has been estimated: 2,2-dihydroxy, 3,5,6,3′,5′,6′-hexachlorodiphenylmethane, 3,4,4′-trichlorocarbanilide, 3,5,4′tribromosalicylanilide, 2,2′-thiobis (4,6-dichlorophenol), Irgasan CF3*, 3,5,3′,4′-tetrachlorosalicylanilide.

3. The results obtained have been discussed in relation to hand-washing test results (Hurst et al. 1960).

1. The fall in the refractive index of mineral oils recovered after injection into the peritoneal cavity of mice is usually accompanied by a fall in the density proportional to the fall in the index.

2. With straight distillates from the crude oil the ratio of index fall to density fall is on an average about 0·85 to 1. Wide deviations from these figures were rarely found except when dealing with oils of low toxicity. The ratio tends to be above the mean when the actual index fall is low and consequently below the mean when the index fall is high.

3. The refractivity of the original oil, the index fall of the recovered oil and the density fall of the recovered oil give information as to the carcinogenic potency for mice of the original oil of about equal value, but the two lastmentioned tests are far superior to the first for assessing the probable dermatitic potency of the oil.

4. Other things being equal, the index and density fall are closely dependent upon the index, density and viscosity of the original oil.

5. The index and density fall gradually become larger as the experiment progresses, but within each 24-hour interval the fall gradually becomes less. The ratio of index fall to density fall remains fairly constant for each individual oil during the course of the experiment.

6. Titration of mineral oils in vitro with sulphuric acid and alcohol provides residual oils of lower index and density than the original oil, but the ratio of the fall in index to the fall in density is low, especially when the treatments are not severe.

7. Oxidation of mineral oils tends to raise the density without affecting the index to an appreciable extent. On the other hand reduction tends to lower the index without affecting the density to anything like the same extent.

8. In general terms the animal reacts upon the chemically treated oils in an additive manner, so that if by the chemical treatment we have the ratio of index fall to density fall low, the oil recovered from the animal will have the ratio high, and vice versa. The end product of the severe treatment of a mineral oil with acid and clay is a white oil which for practical purposes may be considered to be fully saturated. The end product of an oil recovered from the animal is probably similar in nature, although the process involved in arriving at this end product is presumably different chemically and physically.

9. Synthetic oils recovered from the animal after inj ection showed a marked rise in density but no corresponding rise in index.

10. The animal reaction to an injected oil was not materially accelerated by emulsification of the oil.

11. Some chemically pure non-carcinogenic compounds were very rapidly changed or eliminated from the peritoneal cavity.

12. All alcohol extracts of mineral oils tested showed an increase in index, density and refractivity, but not always in viscosity compared with the original oil, the residues, of course, having characteristics in an opposite direction. The latter were in every instant less toxic for the animal than the original oil, whether applied to the skin or injected.

13. A mineral oil recovered from animals 7 days after injection, when reinjected into a second series of animals, was altered as regards its physical characters in a normal manner. Thus whether allowed to remain in the peritoneal cavity of an animal of the first series or recovered and reinjected into an animal of the second series, the ultimate index and density fall in a given time were approximately similar.

14. The free oil in the peritoneal cavity becomes, from day to day, less. This is at least partly due to local trapping by the proliferating endothelium. The fall in index of the trapped oil is approximately similar to that of the free oil.

15. The alteration of the physical characteristics of mineral oils by the animal is probably brought about by a chemical reaction followed by removal of the changed product.

In the two preceding communications we have discussed the calcium balances and weight increase of natives, both adult and growing, on certain institution diets, with and without additions.

Various considerations pointed to a relative or absolute deficiency of calcium in the above diets. The experimental additions made, therefore, were (1) a mineral mixture reproducing closely the ash of cows' milk; (2) cod-liver oil; (3) cod-liver oil plus the mineral mixture; (4) olive oil plus KI; (5) milk.

1. One hundred lepers were examined by Browning, Cruickshank and McKenzie's modification of the Wassermann reaction with positive results in 22 cases. The amount of complement deviated was in some cases exceptionally large.

2. In a control group of 110 non-leprous persons there were 11 positive reactions.

3. In only one of the lepers was there visible evidence of former venereal disease but 33 of the lepers admitted that they had suffered from syphilis or from chancres, and of these 33, 13 reacted positively, while only nine of the remaining 66 gave positive reactions.

4. In the control group, 21 admitted former syphilitic infection and, of these, eight reacted positively; among the remaining 89, who denied syphilis, there were three positive reactions.

5. There were 12 positive reactions among 44 cases of tubercular leprosy and 10 positive reactions among 56 cases of the anaesthetic type.

6. The average duration of the disease, among the 22 lepers who reacted positively, was four years and eight months, as compared with an average of three years and eight months for the 78 patients who reacted negatively; but among the latter there were many old-standing cases.

7. Seventeen of the 22 positive cases were in an advanced stage of leprosy and in some of them the disease was progressing; but among those lepers who reacted negatively there were also many advanced and progressing cases.

8. Serum from the lesions in 10 of the lepers who reacted positively was examined by dark-ground illumination, but in no case was the Treponema pallidum found.

9. The luetin test was applied to 21 lepers, with negative results in every instance; 13 of these cases gave positive and eight gave negative Wassermann reactions. The test was also applied to a control group of non-leprous persons selected because they were likely to be latent syphilitics. In this group there were 11 positive luetin reactions.

Sub-lethal exposure of Aspergillus fumigatus spore suspensions to formalin resulted in prolongation by 1–22 days of the period of less than one day normally needed by spores to produce visible growth in Sabouraud's liquid medium at 37° C.; the degree of delay depended on the concentration of formalin and the duration of exposure, and was due to an increase in the germination-time of spores. The formalin concentration could be adjusted so as to affect the germination-time of almost all spores in a suspension without reducing viability. The effect on germination was not abolished by thorough washing or treatment with sodium sulphite. The spores of four different strains of A. fumigatus and of cultures aged 3 to 14 days reacted similarly to formalin treatment. Although of greatly reduced virulence for mice, affected viable spores were still capable of producing infection and death following intravenous inoculation, provided they were not eliminated by the host before germination occurred.

1. We have investigated bacteriologically the conditions in a central meals kitchen from which about 3000 meals were issued daily to some 65 departments.

2. Plate counts showed that the containers in which the meals were sent out contained large numbers of organisms, from several thousand to several hundred thousand per container.

3. Counts of this order were obtained both before and after the routine method of washing.

4. These counts were reduced to the order of a few hundred or less per container by steam sterilization.

5. Exposure for 2–3 min. to steam from a simple jet sterilizer was effective for all except large insulated lids which required at least 5 min.

6. Treatment for 5 min. in a chamber filled with steam from a boiler was effective with all types of containers and lids tested.

7. If containers are to be sterilized at all they must be sterilized each time they are to be used.

8. A great improvement in the bacteriological counts can be achieved by attention to the hygiene of washing, e.g. by the use of plenty of hot water with soap and soda or perhaps preferably with detergents, with a second sink of very hot water for rinsing, and by using fresh sterilized dish-cloths each time the washing water is changed.

9. Counts almost as good as those given by steam sterilization were obtained by washing with soap and water at 48–50° C., wiping with a sterilized dish-cloth and then rinsing in a second sink of water at 75–80° C.

10. The arguments for and against steam sterilization are discussed.

This investigation was greatly helped by the co-operation of the Leicester Education Department.

Peripheral blood viral load is an important indicator of viral production and clearance. Previous studies have suggested that viral load might predict the rate of decrease in CD4+ cell count and progression to AIDS and death. Here, we conducted a retrospective analysis of the trends in HIV-1 viral load in southeast China. Among inpatients newly diagnosed with HIV infection, we found that viral load has increased over the past decade from 4·20 log10 copies/ml in 2002 to 6·61 log10 copies/ml in 2014, with a mean increase of 0·19 log10 copies/ml each year. However, the CD4+ cell count was stable and insensitive to changes in viral load. Thus, increasing viral load appears to be an emerging trend in newly diagnosed HIV-infected inpatients.

A Canadian outbreak investigation was initiated in January 2022 after a cluster of cases of Shiga-toxin-producing Escherichia coli (STEC) O157 was identified through whole genome sequencing (WGS). Exposure information was collected through case interviews. Traceback investigations were conducted, and samples from case homes, retail, and the manufacturer were tested for STEC O157. Fourteen cases were identified in two provinces in Western Canada, with isolates related by 0–5 whole genome multi-locus sequence typing allele differences. Symptom onset dates ranged from 11 December 2021 to 7 January 2022. The median age of cases was 29.5 (range 0–61); 64% were female. No hospitalisations or deaths were reported. Of 11 cases with information available on fermented vegetable exposures, 91% (10/11) reported consuming Kimchi Brand A during their exposure period. The traceback investigation identified Manufacturer A in Western Canada as the producer. One open and one closed sample of Kimchi Brand A tested positive for STEC O157, with isolates considered genetically related by WGS to the outbreak strain. Napa cabbage within the kimchi product was hypothesised as the most likely source of contamination. This paper summarises the investigation into this STEC O157 outbreak associated with kimchi, the first reported outside of East Asia.

This investigation was initiated when twelve miners who were working in a certain part of the Mill Close Lead Mine complained of smarting of the eyes associated with marked congestion of the conjunctivae. They also suffered from a stinging sensation in the nose and throat. The particular area in which they were working differed from other parts of the mine in that there was a strong smell of sulphuretted hydrogen present. After recovery, and when the ventilation had been improved, the men were able to continue working in that area without experiencing further discomfort. The interesting part of the investigation was tracing the origin of the sulphuretted hydrogen. The odour proceeded from collections of mine water which the miners very appropriately called “stink water”. In this there was a deposit of sulphur mixed with black sludge which also smelt strongly of H2S. The sludge consisted of slightly gelatinous black masses mixed with a whitish felt work of a filamentous organism. On microscopical examination the filaments were seen to contain sulphur globules, and often to arise from a mass of black material. This black material consisted of sulphur and inorganic salts in a slimy matrix, the black colour being due to the presence of ferrous sulphide. On further examination these masses were found to be teeming with other bacteria, Gram-negative bacilli and spirilla, both of which were motile, the spirilla being actively so.

Following the report of the first COVID-19 case in Nepal on 23 January 2020, three major waves were documented between 2020 and 2021. By the end of July 2022, 986 596 cases of confirmed COVID-19 and 11 967 deaths had been reported and 70.5% of the population had received at least two doses of a COVID-19 vaccine. Prior to the pandemic, a large dengue virus (DENV) epidemic affected 68 out of 77 districts, with 17 932 cases and six deaths recorded in 2019. In contrast, the country's Epidemiology and Disease Control Division reported 530 and 540 dengue cases in the pandemic period (2020 and 2021), respectively. Furthermore, Kathmandu reported just 63 dengue cases during 2020 and 2021, significantly lower than the 1463 cases reported in 2019. Serological assay showed 3.2% positivity rates for anti-dengue immunoglobulin M antibodies during the pandemic period, contrasting with 26.9–40% prior to it. Real-time polymerase chain reaction for DENV showed a 0.5% positive rate during the COVID-19 pandemic which is far lower than the 57.0% recorded in 2019. Continuing analyses of dengue incidence and further strengthening of surveillance and collaboration at the regional and international levels are required to fully understand whether the reduction in dengue incidence/transmission were caused by movement restrictions during the COVID-19 pandemic.

In autumn 1978 an epidemic of respiratory disease resembling allergic alveolitis occurred in a small Finnish community. The disease was caused by repeated exposures to tap water aerosol. The raw water of the community and the sand filters of the purification system were heavily contaminated with mesophilic actinomycetes. Fourteen different strains of actinomycetes were isolated. Exposed persons with and without symptoms as well as unexposed control persons were tested for antibodies against five of these actinomycetes and against Enterobacter agglomerans. Both the exposed and the control persons had antibodies to actinomycetes but the exposed persons had antibodies against more actinomycete strains than the control persons. Precipitating antibodies against E. agglomerans were also found in control persons as well as in patients. There was a significant difference between the patients and the exposed healthy persons in bacterial agglutination tests with flagellar antigen of one E. agglomerans strain. However, the role of mesophilic actinomycetes and E. agglomerans in the aetiology of the disease could not be firmly established.

Sera from patients with Crohn's disease more often than those from other subjects contain agglutinins against anaerobic coccoid rods, identified as Peptostreptococcus productus, Eubacterium contortum (two strains) and Coprococcus comes. The presence of antigens of the four coccoid rods in faeces of patients with Crohn's disease and healthy subjects was investigated by inoculation of rats with faecal suspensions. Antigens of the coccoid rods were detected in faeces from both patients with Crohn's disease and healthy subjects.

“Health is more affected by atmospheric conditions than by any other influence. From the moment the new born child utters its first cry, until life finally ceases, he is directly and immediately dependent on the atmosphere he breathes for continued existence. Records of sickness and of mortality clearly show that the nearer atmospheric conditions are to those of the open country, the better is the health of the population, and that the more these conditions are modified owing to urbanisation and industrialisation, the more pronounced is the ill-effect upon general health” (1).

In late 2011 the New Zealand Ministry for Primary Industries reported an increase in confirmed laboratory diagnoses of salmonellosis in dairy herds. To identify risk factors for herd-level outbreaks of salmonellosis we conducted a case-control study of New Zealand dairy herds in 2011–2012. In a multivariable analysis, use of continuous feed troughs [adjusted odds ratio (aOR) 6·2, 95% confidence interval (CI) 2·0–20], use of pelletized magnesium supplements (aOR 10, 95% CI 3·3–33) and use of palm kernel meal as a supplementary feed (aOR 8·7, 95% CI 2·5–30) were positively associated with a herd-level outbreak of salmonellosis between 1 July 2011 and 31 January 2012. We conclude that supplementary feeds used on dairy farms (regardless of type) need to be stored and handled appropriately to reduce the likelihood of bacterial contamination, particularly from birds and rodents. Magnesium supplementation in the pelletized form played a role in triggering outbreaks of acute salmonellosis in New Zealand dairy herds in 2011–2012.

1. Direct conglutination has been demonstrated with Rickettsia burneti.

2. Sera from human volunteers inoculated with killed suspensions of R. burneti and from persons who had recovered from an attack of Q fever as well as sera from a small number of healthy blood donors were all examined by the direct conglutination reaction, the haemolytic-complement fixation test and the direct agglutination test. A good correlation was found between the titres of the direct conglutination reaction and the haemolytic complement-fixation test but the results with the direct agglutination test were unreliable.

1. The effects of morphine, heroin, codeine, dilaudid, dicodid and eukadol upon the caecum and colon are described.

2. Small quantities of morphine produce a rapid increase in tone and amplitude of movements lasting many hours. Large doses result in a spastic contraction of the intestine with diminution of peristaltic movements.

3. The effects of heroin closely resemble those of morphine; it usually produces a greater increase in tone than morphine but the movements are not so great. Heroin is about 30% more active than morphine.

4. Codeine appears to be the weakest member of the series. It causes a slight increase in tone and peristaltic movements which never last very long.

5. Dilaudid produces effects which closely resemble those of morphine and heroin but it is approximately 7.5 times more potent than morphine. Intestinal tone is increased at first but may be subnormal at the 3 or 4 hr. stage. The maximum amplitude of peristaltic movements is seen at the 3 hr. stage.

6. Dicodid increases the tone, and particularly the peristaltic movements. The effects upon the general tone are moderate, much less than those of morphine, heroin or dilaudid. The increase in the amplitude of the movements is, however, much greater than with any other of the drugs. It differs from the others in producing its effects only after a long latent interval of 1–2 hr.

7. Eukadol increases the peristaltic movements in a marked way and is more active in this respect than either morphine or heroin, but is inferior to dicodid. Its effects upon tone are very transient and never very marked.

8. The effects of all these drugs upon the tone and peristaltic movements are at once abolished by adrenalin or atropine. Except morphine and eukadol, these drugs failed to produce their effects when administered after full doses of atropine.

9. The injection of hypophysin during the phase of increased muscular activity following the injection of these drugs, always causes an immediate abolition or diminution of the peristaltic movements and loss of tone to a subnormal level. There is however a rapid recovery from this state and approximately 5–10 min. later the movements are increased to an amplitude far in excess of that seen perior to the injection of hypophysin.

A virus was isolated from fifteen of nineteen children living in an infants' home during an outbreak of diarrhoea. The virus possesses many of the characteristics of the enterovirus group but is serologically distinct from any of the accepted members of this group. It is non-pathogenic for unweaned mice, non-cytopathic in tissue cultures of monkey kidney, but is rapidly cytopathic for tissue-cultured cells of human origin. It is serologically similar to virus Hu 659 isolated by Abrahams in the United States (personal communication).

I should like to thank the Director-General of Public Health and State Psychiatric Services, New South Wales, for permission to publish.