It is generally accepted that the infection of many diseases is conveyed by the discharge of droplets containing the biological materies morbi in the acts of coughing, speaking, etc. In some cases, for instance that of measles, it is believed that if a person harbouring the materies morbi has the opportunity of projecting it upon the upper respiratory tracts of non-immunes, a considerable proportion of the latter will develop the clinical disease. In other cases, for instance cerebro-spinal fever or acute poliomyelitis, it is believed that although, in consequence of the activity of the primary source of infection, many other persons will acquire and harbour the materies morbi only a small proportion of them will develop the disease.

Two single-tube media, lactose-tryptone-lauryl sulphate broth (LTLSB) and lauryl-tryptose-mannitol broth were tested in parallel in a series of 1111 tests on water samples from a variety of sources.

LTLSB was found to be superior both in gas and indole production from Escherichia coli when incubated at 44 °C and is recommended as the most suitable single-tube confirmatory test for this organism.

Resistance of faecal Escherichia coli to ampicillin, tetracycline, sulphamethoxazole and gentamicin was studied in patients admitted to seven different departments in two hospitals. The resistance to ampicillin, tetracycline and sulphamethoxazole in the seven patient groups was 27–57%, 26–56% and 35–63%, respectively. Resistance to gentamicin was found in only one department. An E. coli flora predominantly resistant to ampicillin, tetracycline or sulphamethoxazole (> 50% of the E. coli strains in a faecal sample resistant) was found in 10–38%, 4–30% and 21–35% of the samples. A cross-sectional study focusing on the influence of the use of antimicrobial agents on the occurrence of resistant strains revealed a positive correlation between the annual turnover of broad-spectrum penicillins in various departments and the occurrence of predominantly ampicillin-resistant E. coli strains in these departments.

The chemical changes which occur in the dissolved solids of sewage on discharge into sea-water have been investigated by several workers (see references 1–11). Some observation on the difference of these changes to those occurring in polluted fresh water have been made by Letts and Richards (6,11). In regard to waters whose saline composition is not such as to preclude their admissibility for potable purposes on this account, Liversidge(12) has made a brief communication on the variation in the free and albuminoid ammonia.

Mice were immunized against Salmonella typhimurium with graded doses of heat-killed (HK) and acetone-killed (AK) vaccines and then challenged by the oral or intraperitoneal routes with two doses of S. typhimurium. HK and AK vaccines gave good protection against an intraperitoneal challenge, but failed to protect against an oral challenge which is presumably the natural mode of infection. HK vaccine was as potent as AK vaccine in reducing the mortality rate among mice challenged by the intraperitoneal route but, unlike HK vaccine, AK vaccine was also able to reduce the infectivity rate. With a small intraperitoneal challenge dose it was observed that a gradual increase in vaccine dose is associated with a corresponding fall in mortality rate, but with a larger challenge dose an increase in vaccine dose was associated with a corresponding increase in mortality rates. It was concluded that the protective potency of this type of vaccine may partly depend upon the total amount of antigen in the animal, i.e. including both the vaccine and the challenge organisms, at a critical time after challenge.

A variety of factors that affect lecithinase activity and lecithinase production by Cl. welchii were studied. The lecithinase activity was time and temperature dependent. The optimum temperature varied from 30° to 46° C. according to the strain of Cl. welchii employed. Maximum lecithinase activity was produced after 12–60 hr. There was considerable strain variation. This could easily account for the differences in the published data.

Commercial purified lecithinase was more readily destroyed by heat than the lecithinase produced by Cl. welchii in culture media. The enzyme inactivation pattern at 60° C. was similar to that at 90° C. This is not in agreement with the reports of others who found that less enzyme was inactivated at the higher temperatures.

Acid pH values completely inactivated the enzyme. However, alkaline pH values did not significantly destroy the enzyme. The lecithovitellin reaction was completely inhibited at pH values of 1–5. The optimum pH for the reaction was around pH 7–8.

The production of lecithinase was dependent upon the pH of the culture medium. One strain produced measurable lecithinase at pH values of 5·5–8·5, whereas another strain produced lecithinase only at pH values 6–5–7–5.

Lecithin stimulated the production of lecithinase in a chemically defined medium.

We carried out a retrospective study of acute gastroenteritis (AGE) outbreaks reported between 1 January 2015 and 31 December 2021 in Catalonia (Spain) to compare the incidence from 2015 to 2019 with that observed from 2020 to 2021. We observed a higher incidence rate of outbreaks during the prepandemic period (16.89 outbreaks/1,000,000 person-years) than during the pandemic period (6.96 outbreaks/1,000,000 person-years) (rate ratio (RR) 0.41; 95% confidence interval (CI) 0.34 to 0.51). According to the aetiology of the outbreak, those of viral aetiology decreased from 7.82 to 3.38 outbreaks/1,000,000 person-years (RR 2.31; 95% CI 1.72 to 3.12), and those of bacterial aetiology decreased from 5.01 to 2.78 outbreaks/1,000,000 person-years (RR 1.80; 95% CI 1.29 to 2.52). There was a great reduction in AGE outbreaks in Catalonia. This reduction may have been due to the effect of the nonpharmaceutical measures applied to reduce the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the collapse of the healthcare system and epidemiological surveillance services may also have had a strong influence.

There has been a lack of information on vaccine acceptance for Finnish adults. We conducted a secondary analysis of cross-sectional data collected through the Finnish Medicines Agency Medicine Barometer 2021 survey (response rate: 20.6%). We described and explained vaccine acceptance by investigating the associations between socio-demographic factors and statements using logistic regression and conducted a factor analysis. The majority of respondents (n = 2081) considered vaccines to be safe (93%), effective (97%), and important (95%). However, 20% and 14% felt they did not have enough information about vaccines and vaccine-preventable diseases (VPDs), respectively. Respondents aged 18–39 were 2.8 times more likely to disagree that they had enough information about VPDs compared to respondents aged 60–79 (p < 0.001), while respondents with poorer self-perceived health were 1.8 times more likely to declare not having enough information about vaccines (p < 0.001). We generated three-factor dimensions from the eight statements. They were related to ‘Confidence and attitudes towards vaccines’, ‘Access to information on vaccines and VPDs’, and ‘Debate on vaccine issues’, which may reflect the underlying thinking patterns. Access to and understanding of information about vaccines and VPDs need to be improved for Finnish adults to increase vaccine acceptance and uptake, thus preventing the spread of VPDs.

The residential home was investigated to study the endemic virus population. During this study, oral poliovirus vaccine was given to the children and the effect of vaccination on endemic enteroviruses and adenoviruses was investigated. In the light of these findings, the problem of virus interference is discussed. The health of the children is related to their virus infections.

We are indebted to Prof. S. D. M. Court and Prof. C. A. Green for the active interest they have taken in this investigation; to Miss J. McQuillin, B.Sc., F.I.M.L.T., for her technical assistance; also to the matron of the home and her staff for their co-operation in supplying the specimens, and to Mr L. J. Whitlock of the Royal Victoria Infirmary and his staff for arranging their transport to the laboratory.

Although multiple cases of acute rheumatism have been observed to follow waves of streptococcal infection in institutions (see Green, p. 369) there is doubt as to whether acuter heumatism itself becomes epidemic under such circumstances or whether the element of infectivity lies in the preliminary throat infection as concluded by Sheldon (1931).

The report investigates the variation in results noticed when testing iodophor disinfectants in the presence of a 5% (w/v) yeast suspension.

It was found that these variations were not related to individual iodophor formulations but bore a direct relationship with the storage time of the prepared yeast suspension.

A method for the estimation of chloramphenicol in faeces and bile is described. It has been shown that the bile contains high concentrations of the antibiotic, but the faeces small amounts. It is considered that the faecal concentration is dependent on the biliary supply.

The action of chloramphenicol on the gut flora is described and the dominance of yeasts on complete suppression of the conforms is reported, drawing attention to the possibility of intestinal moniliasis following unrestricted use of the antibiotic.

An explanation of ‘relapses’ in the chloramphenicol treatment of typhoid fever is given, and the possible effect of chloramphenicol on immunity response is discussed.

A new type of Salmonella (S. rubislaw), exhibiting alpha-beta phase variation and found to have caused enteritis in man, has been described. Its antigenic formula is XI, r ↔ e, n, x.

The aim of this study was to determine the extent to which selective under-coverage of births to mothers more likely to be at risk of HIV-1 infection will result in a significant underestimation of the true neonatal seroprevalence. Census data, local birth statisties, maternity data and data from the prevalence monitoring programme were used to produce a model to predict the effects of under-coverage in the uptake of neonatal metabolic screening which has been observed in babies with a mother of ethnic group black African. The adjustment factor which allows for under-coverage is the relative inclusion ratio (RIR); the probability that samples from a group at different risk of HIV infection were included in the survey divided by the probability of inclusion for samples from all other babies. The RIR was found to be close to unity (0·97), indicating a minimal bias. Under usual conditions only if the relative inclusion ratio (RIR) declined to values of 0·87 or below would there be a substantial bias. Despite some selective under representation, the results obtained from the Unlinked Anonymous HIV Monitoring Programme Dried Blood Spot Survey would seem to identity levels of prevalence in the population of child-bearing women with a good degree of accuracy and remains a useful tool for resource allocation, planning of services, provision of care and counselling.

An account is given of outbreaks of anthrax among mink, which occurred in Great Britain during 1936–8, and the possible danger to human beings from this source is discussed. Attention is called to the peculiar features of one of the outbreaks and to the probable mode of infection.

Acknowledgements. My best thanks are due to Dr D. Jordan Lloyd for supplying information and references concerning the dressing of pelts, to the Veterinary Department of the Ministry of Agriculture for details of outbreaks of anthrax during 1936–8, and to Dr F. C. Minett for his assistance in compiling this paper.