Experiments I–VIII.

I shows that under the conditions shown the plates were covered with innumerable colonies 7 feet above ground level to ground level. The beds and trestles were used to keep the hut always uniform.

II shows that 8 feet above ground, i.e. on top of the crossbeams, the same conditions obtain.

III, IV, V, and VI show that the same condition exists in the area between the beds or trestles. The beds make no difference, better or worse.

VII shows practically the same condition high up on the beam between the beds. The inverted plates naturally show less colonies, as the organisms mostly fall on to the plates.

VIII confirms the above.

There is only one conclusion to draw from these experiments, and that is that practically speaking there is no difference in the number of organisms on the ground floor and 8 feet above it, in the ordinary men’s sleeping huts, Barrack Design 230/14.

The following investigation was undertaken during November and December 1911 with the object of determining the source of infection in a series of cases of anthrax which occurred in the same yarn mill. The investigation resulted in proving that anthrax spores were present in a variety of East India wool and in the yarn manufactured therefrom.

This study compared the likelihood of long-term sequelae following infection with SARS-CoV-2 variants, other acute respiratory infections (ARIs) and non-infected individuals. Participants (n=5,630) were drawn from Virus Watch, a prospective community cohort investigating SARS-CoV-2 epidemiology in England. Using logistic regression, we compared predicted probabilities of developing long-term symptoms (>2 months) during different variant dominance periods according to infection status (SARS-CoV-2, other ARI, or no infection), adjusting for confounding by demographic and clinical factors and vaccination status. SARS-CoV-2 infection during early variant periods up to Omicron BA.1 was associated with greater probability of long-term sequalae (adjusted predicted probability (PP) range 0.27, 95% CI = 0.22–0.33 to 0.34, 95% CI = 0.25–0.43) compared with later Omicron sub-variants (PP range 0.11, 95% CI 0.08–0.15 to 0.14, 95% CI 0.10–0.18). While differences between SARS-CoV-2 and other ARIs (PP range 0.08, 95% CI 0.04–0.11 to 0.23, 95% CI 0.18–0.28) varied by period, all post-infection estimates substantially exceeded those for non-infected participants (PP range 0.01, 95% CI 0.00, 0.02 to 0.03, 95% CI 0.01–0.06). Variant was an important predictor of SARS-CoV-2 post-infection sequalae, with recent Omicron sub-variants demonstrating similar probabilities to other contemporaneous ARIs. Further aetiological investigation including between-pathogen comparison is recommended.

Women infected during pregnancy with TORCH (Toxoplasmosis, Other, Rubella, Cytomegalovirus, and Herpes simplex viruses) pathogens have a higher risk of adverse birth outcomes including stillbirth / miscarriage because of mother-to-child transmission. To investigate these risks in pregnant women in Kenya, we analyzed serum specimens from a pregnancy cohort study at three healthcare facilities. A sample of 481 participants was selected for TORCH pathogen antibody testing to determine seroprevalence. A random selection of 285 from the 481 participants was selected to measure seroconversion. These sera were tested using an IgG enzyme-linked immunosorbent assay against 10 TORCH pathogens. We found that the seroprevalence of all but three of the 10 TORCH pathogens at enrollment was >30%, except for Bordetella pertussis (3.8%), Treponema pallidum (11.4%), and varicella zoster virus (0.5%). Conversely, very few participants seroconverted during their pregnancy and were herpes simplex virus type 2 (n = 24, 11.2%), parvovirus B19 (n = 14, 6.2%), and rubella (n = 12, 5.1%). For birth outcomes, 88% of the participant had live births and 12% had stillbirths or miscarriage. Cytomegalovirus positivity at enrolment had a statistically significant positive association with a live birth outcome (p = 0.0394). Of the 10 TORCH pathogens tested, none had an association with adverse pregnancy outcome.

Following the emergence of SARS-CoV-2, early outbreak response relied on behavioural interventions. In the USA, local governments implemented restrictions aimed at reducing movements and contacts to limit viral transmission. In Pennsylvania, restrictions closed schools and businesses in the spring of 2020 and interventions eased later through the summer. Here we use passive monitoring of vehicular traffic volume and mobile device-derived visits to points of interest as proxies for movements and contacts in a rural Pennsylvania county. Rural areas have limited health care resources, which magnifies the importance of disease prevention. These data show the lowest levels of movement occurred during the strictest phase of restrictions, indicating high levels of compliance with behavioural intervention. We find that increases in movement correlated with increases in reported SARS-CoV-2 cases 9–18 days later. The methodology used in this study can be adapted to inform outbreak management strategies for other locations and future outbreaks that use behavioural interventions to reduce pathogen transmission.

Group B streptococcus (GBS) is a major global cause of neonatal, infant, and maternal infections. In Japan, national guidelines based on Centers for Disease Control and Prevention recommendations mandate culture-based screening and intrapartum antibiotic prophylaxis (IAP) for GBS-positive pregnant women. Despite initial reductions in GBS infections, the incidence has plateaued, and there are notable limitations in current prevention methods. Approximately 15% of pregnant women are not screened for GBS, and intermittent colonization undermines screening accuracy, contributing to early-onset disease. IAP does not prevent late-onset disease, the incidence of which is increasing in Japan. This study reviewed maternal and neonatal GBS colonization using polymerase chain reaction, evaluated capsular type distributions, and explored late-onset disease infection routes. Among 525 mother-neonate pairs, the study found a higher detection rate of GBS via polymerase chain reaction compared to culture methods and identified significant discrepancies between antepartum and intrapartum colonization. GBS was detected in 3.5% of neonates from initially negative mothers at 4 days of age. Capsular types varied between mothers and neonates, indicating potential horizontal transmission. This study underscores the need for improved rapid diagnostic tests and highlights the potential of maternal GBS vaccination as a future prevention strategy.

We estimated the number of people unaware of their human immunodeficiency virus (HIV) infection in our province, Pavia (population 540 000) in Lombardy, Italy, by means of anonymous unlinked testing of 10 044 serum/plasma samples residual from clinical analyses at the outpatient clinic of Policlinico San Matteo in 2014 and 2015. Ethical and legal approval was obtained prior to study start. Samples were irreversibly anonymised, only retaining gender and 5-year age class. Five sample pools were tested for HIV using LIAISON® XL MUREX HIV Ab/Ag (DiaSorin, Saluggia, Italy). If the pool tested positive, individual samples underwent confirmatory tests, Innotest HIV Antigen mAb (Fujirebio Europe, Gent, Belgium) and HIV BLOT 2·2 (MP Diagnostics, Singapore). Among the 10 044 samples processed, eight were confirmed positive (0·08%, 95% confidence interval 0·03–0·16%), all were males and age was >50 in 3 (37·5%). If projected to the entire population of the Pavia province, this would result in approximately 1000 people unaware of their HIV infection, with age older than expected. In Italy, HIV testing is voluntary, universally free-of-charge and (upon request) anonymous. Nevertheless, this study demonstrates that it is suboptimally employed, and that new strategies and population-level actions will be needed to achieve better implementation of HIV testing and HIV control in our province.

1. The incidence of haemolytic streptococci in the patients of a Hospital School for rheumatic children was determined over a period of 1 year.

2. In the total of 1644 throat and 1644 nasal swabs, group A strains were isolated from 20 throat and two nasal swabs. Eighty-seven strains of Lancefield's groups C and G and 54 strains of groups other than A, C, or G were isolated

3. There was no evidence of cross-infection.

4. Factors contributing to the low incidence of group A strains and the absence of cross-infection are discussed.

5. The carriage of groups C and G strains did not appreciably affect the erythrocyte sedimentation rate.

6. Although no direct evidence is available, the experience of the present study suggests that the incidence of streptococci in an institution for rheumatic children may be reduced by: (a) bacteriological screening before admission; (b) regular swabbing and Lancefield's grouping of streptococci isolated for the early detection of group A strains; and (c) administration of penicillin or sulphadiazine prophylactically to even a limited number of children.

We thank Prof. R. S. Illingworth for his advice in the writing of this paper, Dr J. L. Emery for laboratory facilities, Dr R. E. O. Williams for his advice in the planning of the investigation, and the matron and sisters of Ash House Hospital School, Sheffield, for their assistance.

The expenses of the investigation were defrayed by a grant from the Medical Research Council.

This paper records the results of systematic pneumococcus typing over a 7-year period in children from 4 days to 12 years of age in the R.H.S.C., Glasgow. Strains typed include those from respiratory tract lesions, from pus in middle ears, meninges, joints, serous sacs and miscellaneous purulent foci. A series of strains from normal throats serves for comparison.

The constant prevalence year by year of types 6, 19, 1 and 23 in all types of disease is striking. On dividing the cases into those under and over 2 years, the incidence of type 1 in the older children is four times that in the younger group. Conversely in those over 2 the incidence of the higher types (21–32) is only half that in the younger patients. No other significant difference in type distribution is observed on comparing the two age groups. Group IV pneumococci are commonly carried in the healthy nasopharynx, and are potential pathogens in young children in whom broncho pneumonia is generally an endogenous infection. There is evidence that the same type of pneumococcus frequently invades the entire respiratory tract and the middle ears. Only thirty of our cases were in the neonatal period and the apparent immunity of the newborn to the pneumococcus is discussed.

The clinical and molecular epidemiology of glycopeptide-resistant Enterococcus faecium was investigated during an outbreak on a renal unit. Forty-nine patients were colonized or infected during a 15-month period. Sites of colonization included faeces, urine, intravenous (IV) catheter tips and wound swabs. Ten patients had infections, which included five bacteraemias and three episodes of peritonitis. Pulsed-field gel electrophoresis of 43 patient isolates of glycopeptide-resistant E. faecium identified seven strains during the first 7 months of the outbreak. Three of these strains affected five or more patients. One strain accounted for 17/43 isolates. Isolates that were possibly related to another renal unit strain were cultured from patients at two other Manchester hospitals. These isolates were epidemiologically-related, and may represent a single Manchester epidemic strain. Of five patients who had multiple isolates of glycopeptide-resistant E. faecium, three had isolates representing a single strain and two were colonized or infected by more than one strain.

The incidence of reported infections of non-typhoid Salmonella is affected by biases inherent to passive laboratory surveillance, whereas analysis of blood sera may provide a less biased alternative to estimate the force of Salmonella transmission in humans. We developed a mathematical model that enabled a back-calculation of the annual seroincidence of Salmonella based on measurements of specific antibodies. The aim of the present study was to determine the seroincidence in two convenience samples from 2012 (Danish blood donors, n = 500, and pregnant women, n = 637) and a community-based sample of healthy individuals from 2006 to 2007 (n = 1780). The lowest antibody levels were measured in the samples from the community cohort and the highest in pregnant women. The annual Salmonella seroincidences were 319 infections/1000 pregnant women [90% credibility interval (CrI) 210–441], 182/1000 in blood donors (90% CrI 85–298) and 77/1000 in the community cohort (90% CrI 45–114). Although the differences between study populations decreased when accounting for different age distributions the estimates depend on the study population. It is important to be aware of this issue and define a certain population under surveillance in order to obtain consistent results in an application of serological measures for public health purposes.

The British Standard Technique for Determining the Rideal-Walker Coefficient of Disinfectants (no. 541—1934), in laying down the procedure to be adopted with regard to the test typhoid bacillus culture, recommends that a fresh culture be obtained each month from the National Collection of Type Cultures. In all probability this is the best procedure; it does, however, sometimes happen that a test is required urgently when a fresh culture is not available. The following notes upon our own experience in maintaining cultures may therefore be of some interest. It is our practice to obtain fresh cultures whenever we are called upon to carry out other than routine tests unless a recent one has been obtained, and many of these cultures have now been running for a number of years. On the arrival of the culture from the N.C.T.C. it is subcultured on to an agar slope and “incubated” at room temperature in a dark cupboard. 2% agar is used in a broth prepared by the tryptic digestion of ox heart. Further subcultures are made at intervals of one month. It is our usual practice to start a series of broth cultures from such slopes not less than 14 days after sowing.

There is limited information on the antibody responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in subjects from developing countries with populations having a high incidence of co-morbidities. Here, we analysed the immunogenicity of homologous schemes using the ChAdOx1-S, Sputnik V, or BNT162b2 vaccines and the effect of a booster dose with ChAdOx1-S in middle-aged adults who were seropositive or seronegative to the SARS-CoV-2 spike protein before vaccination. The study was conducted post-vaccination with a follow-up of 4 months for antibody titre using enzyme-linked immunosorbent assay (ELISA) and pseudovirus (PV) neutralization assays (PNAs). All three vaccines elicited a superior IgG anti-receptor-binding domain (RBD) and neutralization response against the Alpha and Delta variants when administered to individuals with a previous infection by SARS-CoV-2. The booster dose spiked the neutralization activity among individuals with and without a prior SARS-CoV-2 infection. The ChAdOx1-S vaccine induced weaker antibody responses in infection-naive subjects. A follow-up of 4 months post-vaccination showed a drop in antibody titre, with about 20% of the infection-naive and 100% of SARS-CoV-2 pre-exposed participants with detectable neutralization capacity against Alpha pseudovirus (Alpha-PV) and Delta PV (Delta-PV). Our observations support the use of different vaccines in a country with high seroprevalence at the vaccination time.

The use of the hypergeometric distribution in calculations of sample volumes for safety testing is criticized. Alternative interpretations of the concept of ‘infective ml. doses’ lead to slightly different solutions, the simplest of which, involving the exponential function, is recommended for general use.

The Arizona Department of Health Services identified unusually high levels of influenza activity and severe complications during the 2015–2016 influenza season leading to concerns about potential increased disease severity compared with prior seasons. We estimated state-level burden and severity to compare across three seasons using multiple data sources for community-level illness, hospitalisation and death. Severity ratios were calculated as the number of hospitalisations or deaths per community case. Community influenza-like illness rates, hospitalisation rates and mortality rates in 2015–2016 were higher than the previous two seasons. However, ratios of severe disease to community illness were similar. Arizona experienced overall increased disease burden in 2015–2016, but not increased severity compared with prior seasons. Timely estimates of state-specific burden and severity are potentially feasible and may provide important information during seemingly unusual influenza seasons or pandemic situations.

Ankylostomiasis was first discovered in men working in Cornish mines in October, 1902 (this Journal, Vol. III. p. 95), though there had been many cases of illness clearly referable to this cause for some eight years previously. The number of men who were too ill to do their ordinary work was greater about two years before the cause of “Dolcoath anaemia” was identified. These men had either stopped at home or had been employed on the surface instead of underground: in this way they had avoided further infections, and in many cases had progressed towards a spontaneous cure. At the time therefore of our first enquiry the number of sick men was less than it had been. Anaemic miners were, however, still very numerous and, without anything like an exhaustive search among the 750 underground hands at Dolcoath mine, we found 14 men with less than 50 p.c. haemoglobin and 19 more with less than 75 p.c. The general pallor prevalent among the men on looking at a shift as a whole was very striking, and complaints of shortness of breath on climbing the ladders were frequent. The disease, in short, was at that time a meterial hindrance in carrying on the work of the mine.

Two hundred and sixty-four samples of sera obtained from normal healthy persons belonging to different age groups were examined for haemagglutination-inhibiting antibodies against reovirus types 1–3 to assess the prevalence of reovirus infection in the northern part of India.

Reovirus infection appeared as early as 6 months to 1 year of age. With reovirus types 1 and 2, the maximum incidence of 67 and 48% respectively occurred by the age of 10–20 years, whereas with type 3 infection the maximum incidence (73%) was reached by the age of 25 years. The incidence of reovirus type 2 infection in all the age groups was remarkably low in this series. A drop in the incidence of reovirus type 2 infection was also noticed after the age of 20 years.

The difference in geometric mean titre of antibody in different ages against reovirus type 2 was highly significant, suggesting probably that most of the infection occurred by the age of twenty years. The difference in the geometric mean value of the titres of antibody against types 1 and 3 was not significant in different age groups. The levels of antibody against types 1 and 3 in all the age groups were almost the same, suggesting that infection, specially with reovirus type 3, was occurring in all the age groups even beyond 20 years of age.

The authors wish to express their sincerest thanks to Dr Leon Rosen, Pacific Research Section, National Institute of Allergy and Infectious Diseases, Honolulu, Hawaii, for the supply of prototype strains of reoviruses, to Drs B. K. Aikat, Director Professor of Pathology, R. N. Chakravarti, Department of Experimental Medicine, O. N. Bhakoo, and Sucheta Thukral, Department of Paediatrics, Post- Graduate Institute of Medical Education and Research, Chadigarh, for their invaluable help and co-operation, to Prof. P. V. K. Iyer, Department of Mathematics, Panjab University, and to Mr H. D. Gupta, Biostatistician, Post-Graduate Institute of Medical Education and Research, Chadigarh for their statistical analysis of the results.

The authors gratefully acknowledge the helpful criticism and suggestion of Dr C G. Pandit, Ex-Director, Indian Council of Medical Research, during the preparation of the paper.

The authors acknowledge also the technical assistance of Mr Jagmohan Lai Pipat, Mr Gurmeet Singh Khatra, and Mr Amar Singh Saini.

This work was partly supported by the Research Grant of the Indian Council of Medical Research sanctioned to one of the authors (S. R. P.).