The vaccination of sheep with one dose of the monkey-and mouse-attenuated tick-borne encephalitis virus (the Hy-HK 28 ‘2’ clone) causes seroconversion from negative into positive in 85% of animals. In sheep with pre-existing virus-neutralizing antibodies and increas of their titres was observed in 81%. The antibodies persisted for at least 12 months after the vaccination and during the summer period of grazing the number of serologically positive animals even increased.

The vaccinated animals, in contrast to the non-immune control sheep, developed no viraemia after challenge with the virulent louping-ill virus, performed 11 months after immunization.

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.

The Florida cotton rat, Sigmodon hispidus, has become established as a laboratory animal largely because it is the best known host of the filariid worm, Litomosoides carinii, which is used in routine screening tests for filariacides.

Cotton rats are unsuitable for infecting when very small, and as the filariae take several months to develop enough for the purpose of the test, most of the cotton rats are fully grown at the time of testing. Their weight range is 125–225 g., average about 170 g.

1. Naturally occurring agglutinins to paracolon bacilli have been found in seven out of ten sera from non-immunized rabbits and in one anti-Salmonella and two anti-paracolon immune rabbits' sera after complete absorption with the immunizing strain.

2. The a antigen of Stamp & Stone, which is known to occur as a natural agglutinin, has been demonstrated in one out of nine paracolon bacilli.

3. Rabbits which before immunization show agglutinins to the immunizing strain or to an α antigen should not be used for the preparation of diagnostic antisera for intestinal Gram-negative bacilli.

1. The ordinary method of calculating the birth-rate does not distinguish between the influence of fertility and of variations in conditions of the population as to age and marriage.

2. In ascertaining the true meaning of the great reduction of the birth-rate which has occured in the last 25 years it is necessary to have means for distinguishing between the accidental and the intrinsic causes of change.

3. A step in the right direction is made when the legitimate births are stated in terms of the married women at child-bearing ages, and the illegitimate births in terms of the unmarried women of the same ages.

4. This method fails to correct for the differences of fertility of the various ages comprised in the age-period 15–45.

5. By calculating standard fertility-rates for given populations McLean overcame the above difficulty, and was thus able to compare experiences of a given community at different times with the standard.

6. In this paper it is shown that by continuing the above process and obtaining corrected fertility-rates, the fertility-rates of different communities can be made directly comparable.

7. The inconveniences of this new and unfamiliar method, and the necessity involved in it of calculating the crude as well as the corrected fertility-rate in every instance, indicate the desirability of obtaining a factor for each community which throughout an entire intercensal period can be applied to the crude birth-rate of that community.

8. The desirability of such a factor is increased by the fact that the method of corrected fertility-rates does not take into account the proportion of married women in each population.

9. In this paper a method is described of obtaining factors, which, when applied to the readily available crude birth-rates, correct completely both for the varying proportion of married women in compared populations and for the varying fertility at different periods of married life.

10. The practical bearings of these corrected birth-rates will be discussed in a later paper.

The aim of our study was to examine the position of vaccinated people regarding the proposal for mandatory and seasonal vaccination against COVID-19 in Serbia. A cross-sectional study was conducted in a sample of people who came to receive a third dose of COVID-19 at the Institute of Public Health of Serbia in September and October 2021. Data were collected by means of a sociodemographic questionnaire. The study sample comprised 366 vaccinated adults. Factors associated with the belief that vaccination against COVID-19 should become mandatory were being married, being informed about COVID-19 from TV programmes and medical journals, trust in health professionals, and having friends affected by COVID-19. In addition to these predictors, factors associated with the belief that COVID-19 vaccination should become seasonal were being older, consistently wearing facemasks, and not being employed. The results of this study highlight that trust in information delivery, evidence-based data, and healthcare providers may be a major driver of mandatory and seasonal vaccine uptake. A careful assessment of the epidemiological situation, the capacity of the health system, and the risk–benefit ratio is needed in order to introduce seasonal and/or mandatory vaccination against COVID-19.

The article aims to estimate and forecast the transmissibility of shigellosis and explore the association of meteorological factors with shigellosis. The mathematical model named Susceptible–Exposed–Symptomatic/Asymptomatic–Recovered–Water/Food (SEIARW) was used to explore the feature of shigellosis transmission based on the data of Wuhan City, China, from 2005 to 2017. The study applied effective reproduction number (Reff) to estimate the transmissibility. Daily meteorological data from 2008 to 2017 were used to determine Spearman's correlation with reported new cases and Reff. The SEIARW model fit the data well (χ2 = 0.00046, p > 0.999). The simulation results showed that the reservoir-to-person transmission of the shigellosis route has been interrupted. The Reff would be reduced to a transmission threshold of 1.00 (95% confidence interval (CI) 0.82–1.19) in 2035. Reducing the infectious period to 11.25 days would also decrease the value of Reff to 0.99. There was a significant correlation between new cases of shigellosis and atmospheric pressure, temperature, wind speed and sun hours per day. The correlation coefficients, although statistically significant, were very low (<0.3). In Wuhan, China, the main transmission pattern of shigellosis is person-to-person. Meteorological factors, especially daily atmospheric pressure and temperature, may influence the epidemic of shigellosis.

Established methods of recruiting population controls for case–control studies in infectious disease outbreak investigations are resource- and time-intensive, and are often subject to bias. The online panel have recently gained interest as an easy and timely method to select controls. We examined the feasibility, suitability and reliability of using an online panel to select controls for case–control studies as part of investigations of diffuse food and waterborne outbreaks. In January 2019, we deployed a web survey by email to the 277 members of a non-probabilistic online panel in Lower Saxony, Germany. We questioned them on basic sociodemographic characteristics and eating habits. They were frequency matched to cases on sex and age. Their food exposures were compared to those of traditionally recruited controls of four historical case–controls studies, which successfully investigated food and waterborne outbreaks. We used logistic regressions to assess the association between the food exposures and the disease (odds ratios). The use of a control panel successfully led to the identification of the food items in three of the four historical outbreak investigations, and their recruitment benefitted from increased speed and limited costs. Timely outbreak investigations would enable rapidly implementing control measures. We recommend the further evaluation of using panellists as controls in parallel case–control studies and case–panel studies.

Seroprevalence estimation using cross-sectional serosurveys can be challenging due to inadequate or unknown biological cut-off limits of detection. In recent years, diagnostic assay cut-offs, fixed assay cut-offs and more flexible approaches as mixture modelling have been proposed to classify biological quantitative measurements into a positive or negative status. Our objective was to estimate the prevalence of anti-HCV antibodies among drug users (DU) in France in 2011 using a biological test performed on dried blood spots (DBS) collected during a cross-sectional serosurvey. However, in 2011, we did not have a cut-off value for DBS. We could not use the values for serum or plasma, knowing that the DBS value was not necessarily the same. Accordingly, we used a method which consisted of applying a two-component mixture model with age-dependent mixing proportions using penalised splines. The component densities were assumed to be log-normally distributed and were estimated in a Bayesian framework. Anti-HCV prevalence among DU was estimated at 43.3% in France and increased with age. Our method allowed us to provide estimates of age-dependent prevalence using DBS without having a specified biological cut-off value.

The want of success which has so persistently attended the efforts of most bacteriologists to isolate the B. typhosus from water supplies suspected to have caused enteric fever, suggested a study of the varieties of B. coli which are associated with the B. typhosus in the dejecta of patients suffering from enteric fever. It was hoped that the organisms in question might show cultural characteristics or reactions to specific sera, which would enable them to be distinguished from the varieties of B. coli present in the dejecta of healthy people; so that even if the B. typhosus were not detected, the presence of these special organisms might afford reasonable grounds for the belief that the water under examination had been fouled by the specific dejecta of cases of enteric fever. With this object in view 150 organisms have been examined; of these 80 were isolated from the stools of cases of enteric fever and 70 from the stools of healthy men. The enteric fever cases were five in number, one being a severe relapse, and the other four severe cases which terminated fatally. The stools were obtained during the third and fourth weeks of the disease and also, in the fatal cases, from the intestines after death had occurred.

It appears to be widely believed that normal human urine as voided is sterile, and that the fact of sterility is capable of ready demonstration.

Individuals developing an HIV seroconversion illness may experience rapid disease progression. Information on seroconversion illness is rarely collected in most cohort studies; thus the aim of this study was to assess the value of the HIV test interval (the time between last negative and first positive HIV tests) as a proxy for seroconversion illness. Among 8229 seroconverters, test intervals ranged from 0–5282 days, and varied by gender, risk group, age and calendar year of seroconversion. Those with intervals [les ] 31 days had an increased hazard of AIDS (RH 1·42, P = 0·07), which was reduced slightly after adjusting for baseline factors, calendar year of follow-up, treatment and the declining CD4 count, but there was no effect on survival. Thus, it appears that if information on acute seroconversion illness is not available, then analyses of progression to AIDS in seroconverter studies could use a short test interval as a proxy measure.

In order to determine whether non-lactose fermenting bacilli are numerous in fresh milk, a series of experiments was made in the early part of this year on samples of fresh dairy milk, taken in Dumfriesshire, for routine bacteriological examination. The samples were brought to the laboratory with the least possible delay, and in no case did more than seven or eight hours elapse between the time of milking and the inoculation of plates. In the majority of instances, the interval was much shorter.

A test is described for assessing the effect of hypochlorites in reducing the bacterial load on soiled napkins during storage, between removal from the infant and the laundering.

One hundred and eleven consecutive deaths in seven mental hospitals during the months of February to October 1967 were investigated histologically and bacteriologically.

Bacteria were present in the lung tissue significantly more frequently when inflammation was present than when it was absent and the differences were significant for both Escherichia coli and Staphylococcus aureus; E. coli was isolated from 22(34%) of the 65 patients with inflamed lungs compared with two (4%) of 46 control patients and the corresponding figures for Staph. aureus were 20(31%) of 65 patients compared with seven (15%) of 46 control patients.

Some strains of E. coli were serotyped using antisera against 0 antigens 1, 4, 6, 18ab, 18ac, 25, 50, 65, 69 and 75 and the strains most commonly found in the inflamed lungs, spleens and other inflammatory lesions of 25 patients were 06, 018 and 075. These strains were isolated more frequently from these sites than from the faeces of a group of 19 patients with no such lesions.

In this series E. coli was the commonest organism to be associated with terminal bronchopneumonia and the possible reasons for this are discussed.

1. A review of the few studies so far made on the high mortality from tuberculosis among elderly men, and a consideration of the available statistics, indicate that urbanization is one of the principal factors responsible.

2. In the present inquiry, which was confined to London, 445 newly diagnosed cases of tuberculosis in men over 40, together with the same number of paired controls, were studied by means of a questionnaire and of personal interview.

3. It was found that the tuberculous patients differed significantly from the controls in the following characteristics; Scots, Irish, Welsh, or foreign nationality; single, widower or divorced; resident in common lodging houses or hostels; inadequate or special diet; history of gastrectomy; a winter cough; shortness of breath; insufficient sleep; and heavy drinking and smoking. On the other hand, overtime or night work, diabetes, rheumatoid arthritis, asthma, and mental illness were distributed fairly evenly in the two groups.

4. Unfortunately no group of elderly women exists in this country living under the same sort of conditions as the elderly men studied here, so that it was impossible to determine how far the various factors considered were responsible for the high rate of late adult male tuberculosis. A study, however, of a population of established civil servants living under ordinary conditions revealed little difference between the observed rates of tuberculosis and those expected on the basis of national notification figures for men and women in the older age groups.

5. It appears that a low standard of personal hygiene, associated especially with heavy smoking and drinking and residence in loading houses, predispose to the development of tuberculosis in the elderly male. Part of the evil effect of living in common lodging houses in particular may be due to the increased risk of exposure to tuberculous infection that it entails.

6. It is tentatively concluded that the casual workers of an urbanized community are one of the principal reservoirs of tuberculous infection in large towns, and since there is no numerically comparable female population, this group, and its immediate male contacts, account in large measure for the difference between the male and female tuberculosis rates in the older age groups.

This work was initiated during the tenure of a Prophit Scholarship of the Royal College of Physicians, and completed with the aid of a grant from the Medical Research Council.

I am indebted to members of the Prophit Committee of the Royal College of Physicians for their support and encouragement, and most particularly to Dr G. S. Wilson, Director of the Public Health Laboratory Service, under whose guidance the work was carried out. Figures relating to the incidence of tuberculosis in the Civil Service are published by kind permission of Dr W. E. Chiesman, Treasury Medical Adviser, and Dr M. C. W. Long, Dr J. W. Parks, and Dr H. Stannus Stannus, whose departmental records were used to compute the figures.

I am greatly indebted to the consultants and staff of the seventeen chest clinics who co-operated in the investigation, for their interest and help in tracing patients, and to the medical superintendents of numerous sanatoria and chest hospitals, and to the surgeons who permitted me to interview patients under their care as controls.

I should like also to acknowledge the assistance received from the medical officers of health of the metropolitan boroughs who kept me informed of notifications from lodging houses in their areas, and supplied information about the accommodation.

Inagglutinable strains of B. typhosus are of considerable interest bacteriologists both from a practical and theoretical aspect. These strains present the usual characteristics of the typhoid bacillus, with exception that they are not agglutinated by anti-typhoid sera, if and such a contingency be overlooked one may fail to recognise that one dealing with a typhoid infection. This feature persists in the subcultures for many months, thus differentiating the inagglutinable strains from the many strains of B. typhosus which agglutinate with difficulty when freshly isolated but which regain their full agglutinability after one or two subcultures. Since their discovery these inagglutinable strains have been investigated on several occasions without any definite agreement as to the condition being arrived at.