Healthy persons were shown to possess circulating antibodies of both IgA, IgG and IgM isotype directed against the bacteria of their faecal microflora, assessed by immunomorphometry. After removal, by absorption, of the fraction of antibodies directed against the autochthonous faecal bacteria or cross-reacting with allogenous faecal bacteria, there were still antibodies left directed against allogenous faecal bacteria of both the IgA, IgG and IgM isotype. However, relatively more antibodies of the IgA isotype appeared to be directed against allogenous bacteria than against indigenous faecal bacteria. Persons who reacted with specific antibodies to many bacteria of their own flora also tended to react specifically to bacteria in the allogenous microflora of the other volunteers. The patterns of antibodies directed to faecal bacteria of different morphologies (morphotypes) were unique for each individual.

Trials of aqueous and oil adjuvant vaccines in young adult volunteers showed that severe local reactions were rare. However, the incidence of minor symptoms was too high for a vaccine which requires to be administered repeatedly. In contradistinction to some reports, systemic and allergic reactions did not constitute a problem.

The food court at a shopping mall is a potential transfer point for pathogenic microbes, but to date, this environment has not been the subject of detailed molecular microbiological study. We used a combination of culture-based and culture-independent approaches to investigate the types and numbers of bacteria present on food court tables, and on a food court cleaning cloth. Bacteria were found at 102–105 c.f.u./m2 on food court tables and 1010 c.f.u./m2 on the cleaning cloth. Tag-pyrosequencing of amplified 16S rRNA genes revealed that the dominant bacterial types on the cleaning cloth were genera known to include pathogenic species (Stenotrophomonas, Aeromonas), and that these genera were also evident at lower levels on table surfaces, suggesting possible cross-contamination. The evidence suggests a public health threat is posed by bacteria in the food court, and that this may be due to cross-contamination between cleaning equipment and table surfaces.

Surveillance for gastroenteritis rarely detects small, intra-familial outbreaks. This study examined intra-household transmission of gastroenteritis using prospectively collected data from 2811 participants (600 households) in a community-based study. There were 258 household clusters of gastroenteritis during the 15 months of observation involving 774 residents (28% of total). Age <6 years and attendance at a day care/kindergarten were associated with increased likelihood of inclusion in a cluster. The reach of illness into the household was extensive, with 63% of household members affected by symptoms during clusters. Simultaneous and secondary transmission of gastroenteritis appeared equally common. In only 20% of clusters did more than one member submit a faecal specimen. Of clusters where two or more specimens were submitted, concordance in laboratory confirmation of pathogens was 18·8%. Our results show that clustering of gastrointestinal symptoms within households occurs commonly, but reliance on pathogen notification data will substantially underestimate the true frequency of gastroenteritis clusters.

The isolation and description of Bacillus coli commune by Escherich a hundred years ago marked the start of a series of scientific investigations which have led to some of the most important discoveries in microbial pathogenicity and genetics that have been made since that time. It is not difficult to find the reasons why so much effort has been concentrated on this organism. Escherichia coli is present in the gut of all warm-blooded animals generally forming the predominant aerobic flora; it is of medical and veterinary importance being responsible for a variety of infections in the human and animal populations and it has provided a useful tool for geneticists.

1. Iodine vapour at a readily tolerable concentration of 0·1 mg./cu.ft. of air gives a rapid kill of freshly sprayed salivary organisms at humidities above 50 %.

2. At the same concentration dry bacteria are not as readily killed, the killing rate only becoming appreciable above 70 % R.H.

The occurrence of epidemics of influenza in Britain since 1957, when the A 2 (Asian) virus was first introduced, has been traced by an analysis of influenza deaths and sickness insurance benefit claims. In a more detailed study of the epidemic in 1967–8, the largest for 7 years, mortality statistics, sickness benefit claims, consultation rates in general practice and laboratory reports were analysed according to time and geographical location, the age distribution of cases and their clinical features. The value of these various indices in the surveillance of influenza is discussed. It is estimated that the number of cases of influenza during the 1967–8 epidemic was just over one million in the working population and almost two millions in the whole population of Britain.

We wish to thank Dr D. L. Crombie, Honorary Director of the Royal College of General Practitioners' Records and Statistics Unit for permission to quote from returns compiled by the Unit and Mrs P. Jones who extracted the information; we also thank Dr A. M. Adelstein of the General Register Office and Dr J. R. Connelly and Dr A. T. Roden of the Department of Health and Social Security for their helpful comments, and the many laboratory directors whose findings are reported in the Communicable Disease Report of the PHLS. We are also much indebted to Mrs R. Narasimhan who helped with the analysis of the data.

In January 2012, an inpatient in a ward of a psychiatric hospital with nearly 300 beds in Kanagawa, Japan, was diagnosed with sputum smear-positive pulmonary tuberculosis (TB). Here we characterise the TB outbreak cases and identify the population at risk. TB was diagnosed when a person tested bacteriologically positive for TB or was determined to have TB by a physician. A latent TB infection (LTBI) case was defined as a person tested positive by interferon-gamma release assay (IGRA). A total of 125 contacts were screened via IGRA and chest X-ray. In all, 15 TB and 15 LTBI cases were found by the end of October 2012, and thereafter no additional TB case was found. Of the 15 TB cases, eight were culture-positive and all the isolates had identical variable number tandem repeat patterns. Twenty-four of the 56 (42.9%, 95% confidence interval (CI) 29.7–56.8) inpatients in the ward had either TB or LTBI with a relative risk of 8.6 (95% CI 1.2–59.3), compared to the staff members who did not work full-time in the ward (one of 20 (5.0%, 95% CI 0.0–24.9)). We recommend that psychiatric hospitals conduct periodic screening of staff members and inpatients for TB to prevent nosocomial TB outbreaks.

1. A typical uncomplicated case of silicosis with fatal outcome in a porcelain turner is described.

2. Microscopic examination of lung tissue and of ashes therefrom showed numerous mineral needles resembling those found in kaolin from his factory.

3. The findings in this case are taken to support in part the theory advanced by W. R. Jones, that silicosis can be produced by fibrous minerals.

We are indebted to Mr Bögvad, M.S., for valuable aid in the mineralogical diagnosis.

In developed countries the majority of hepatitis C virus (HCV) infections occur in injecting drug users (IDUs) with prevalence in IDUs often high, but with wide geographical differences within countries. Estimates of local prevalence are needed for planning services for IDUs, but it is not practical to conduct HCV seroprevalence surveys in all areas. In this study survey data from IDUs attending specialist services were collected in 52/149 sites in England between 2006 and 2008. Spatially correlated random-effects models were used to estimate HCV prevalence for all sites, using auxiliary data to aid prediction. Estimates ranged from 14% to 82%, with larger cities, London and the North West having the highest HCV prevalence. The methods used generated robust estimates for each area, with a well-identified spatial pattern that improved predictions. Such models may be of use in other areas of study where surveillance data are sparse.

Between 21 November and 22 December 2020, a SARS-CoV-2 community testing pilot took place in the South Wales Valleys. We conducted a case-control study in adults taking part in the pilot using an anonymous online questionnaire. Social, demographic and behavioural factors were compared in people with a positive lateral flow test (cases) and a sample of negatives (controls). A total of 199 cases and 2621 controls completed a questionnaire (response rates: 27.1 and 37.6% respectively). Following adjustment, cases were more likely to work in the hospitality sector (aOR 3.39, 95% CI 1.43–8.03), social care (aOR 2.63, 1.22–5.67) or healthcare (aOR 2.31, 1.29–4.13), live with someone self-isolating due to contact with a case (aOR 3.07, 2.03–4.62), visit a pub (aOR 2.87, 1.11–7.37) and smoke or vape (aOR 1.54, 1.02–2.32). In this community, and at this point in the epidemic, reducing transmission from a household contact who is self-isolating would have the biggest public health impact (population-attributable fraction: 0.2). As restrictions on social mixing are relaxed, hospitality venues will become of greater public health importance, and those working in this sector should be adequately protected. Smoking or vaping may be an important modifiable risk factor.

Threads were infected with the spores of four species of bacteria and put inside rubber gloves which were sealed into plastic bags and irradiated with electrons or gamma rays. A dose of 1·5 Mrad. killed approximately 99·99% of the spores of each species and a dose of 2·5 Mrad. appeared to give an adequate margin of safety for sterilization. Spores were similarly killed inside plastic tubing and within the lumen of hypodermic needles.

The tensile strength of the gloves decreased with increasing doses of radiation so that the rough, solution-dipped gloves tested were significantly weaker after 8·0 Mrad., but the smooth gloves tested still complied with the British Standard after 30 Mrad. When vacuum-packed before irradiation, rough gloves were still satisfactory after 16 Mrad., and smooth gloves were apparently unaffected by 30 Mrad.; they could, therefore, be sterilized six and twelve times, respectively.

Radiation gives dependable sterilization of rubber gloves, and the use of a sealed plastic package obviates subsequent contamination. The possibility of using disposable radiation-sterilized gloves is discussed, the use of a plastic radiation indicator suggested and the practical applications of radiation sterilization in the hospital considered.

To determine the pathogenic potential of the vesiculovirus Piry for domestic animals, two ponies, two steers, three sheep, three goats and three pigs were inoculated intradermally in the tongue or, in the case of the pigs, in the snout, heel and coronary band. Inoculated animals were housed in one room and allowed to mingle freely with an equal number of uninoculated contact animals of each species. Clinical signs of infection, consisting of elevated temperature and ulcers at the inoculation sites, were only observed in the ponies, but all inoculated animals developed specific antibody following inoculation. In addition, one of the contact sheep had neutralizing antibody to Piry at 7 and 29 days post inoculation suggesting a contact infection. Virus was not demonstrated in tissues, other than tongue, of any animal.

The failure of Piry virus to produce lesions in steers, sheep, goats and pigs and only limited ulcerations in ponies suggests that this virus is not similar pathogenically to New Jersey and Indiana strains of vesiculoviruses which produce classical vesicular stomatitis.

Lethal infections were produced by inoculation into suckling mice and hamsters, adult hamsters and embryonating chicken eggs. Further, lethal infections followed contact of adult female hamsters with their inoculated litters.

Evidence was presented to support a hypothesis that competition between antibody molecules can be an important factor in vaccinia virus neutralization.

It has been shown that there is little difference in the virus neutralizing properties of 7 S and 19 S antibody and it has been further postulated that in the context of protective immunity the proportions of antibodies having neutralizing and interfering effects is likely to be more important than the absolute concentration of neutralizing antibody or the type of immunoglobulin in which it is present.

(1) A localised epidemic of diphtheria of a clinically mild type (both as regards local and general symptoms) was associated with the prevalence in the fauces of patients and contacts of strains of B. diphtheriae of low pathogenicity for animals; 35% of these strains possessed moderate virulence for guinea-pigs, 30% low virulence and 35% were non-virulent.

(2) Prolonged nasal discharge after moderately severe diphtheria was in one case associated with a strain of B. diphtheriae which was non-virulent for guinea-pigs.

(3) Acid production in various carbohydrate media proved a valuable means of differentiating diphtheria-like bacilli, but the exact composition of the medium is of importance. Peptone water appears to be especially suitable for the basis as being least liable to variation.

(4) The agglutination test gave a fairly uniform result with most of the strains of virulent B. diphtheriae, but three virulent strains did not give a decided positive reaction to this test. Of the non-virulent strains half gave a slight, the remainder a negative result.

Bacillus pseudo-diphtheriae (Hofmann) and certain acid producing diphtheroids gave no reaction.

(5) B. fusiformis and spirochaetes occurred in large numbers on the fauces in this epidemic of diphtheria, in association with the B. diphtheriae.

(6) After all the boys had received prophylactic infections of antitoxin and after the carriers had been isolated the epidemic promptly ceased.

I have to thank Lieut.-Col. Sir Joseph Fayrer, Medical Officer of the Duke of York's School, who was at the time Acting Commandant, for his permission to publish this account.

I am very much indebted to Dr Boycott and Dr Marshall for the very large amount of help which they gave me, and to Dr Dean for his assistance throughout the investigation.

The medical records of 84 patients with stool cultures positive for Clostridium difficile during the period August 2007 to June 2009 were retrospectively reviewed. A case of confirmed (toxigenic) C. difficile infection (CDI) was defined by the presence of symptoms (fever, diarrhoea, abdominal discomfort or distension, ileus) and the presence of toxigenic C. difficile. Patients with compatible clinical symptoms and stool cultures positive for non-toxigenic C. difficile isolates were defined as probable (non-toxigenic) CDI cases. Of these 84 patients, 50 (59·5%) were diagnosed as confirmed CDI and 34 (40·5%) as probable CDI. Thirteen (15·5%) of the 84 patients died during their hospital stay. Usage of proton pump inhibitors was a significant independent risk factor for CDI (OR 3·21, P = 0·014). Of the 50 isolates associated with confirmed CDI, seven (8·3%) carried binary toxin genes (cdtAB), and six (7·1%) had a deletion in the tcdC gene. The mortality rate in confirmed CDI patients with isolates exhibiting deletion in the tcdC gene (2/6, 33·3%), those with isolates harbouring binary toxin genes (2/7, 28·6%), and those with isolates containing mutations in gyrA (2/7, 28·6%) and gyrB (1/2, 50%) was higher than the overall mortality rate (10/50, 20%) in patients with confirmed CDI.

It is difficult to assess the mortality burden of influenza epidemics in tropical countries. Until recently, the burden of influenza was believed to be negligible in Africa. We assessed the impact of the 2009 influenza epidemic on mortality in Madagascar by conducting Poisson regression analysis on mortality data from the deaths registry, after the first wave of the 2009 A(H1N1) virus pandemic. There were 20% more human deaths than expected in Antananarivo, Madagascar in November 2009, with excess mortality in the ⩾50 years age group (relative risk 1·41). Furthermore, the number of deaths from pulmonary disease was significantly higher than the number of deaths from other causes during this pandemic period. These results suggest that the A(H1N1) 2009 virus pandemic may have been accompanied by an increase in mortality.

Studies of group A, M type 49 streptococci from England, Trinidad and Alaska indicate that isolates of this serotype often differ with respect to phage subtype from one geographical areato another, but are generally homogeneous in one place at one time. The findings support the conclusion that acute glomerulonephritis can be associated with a variety of phage subtypes of M type 49 streptococci.

In outbreaks of skin sepsis without nephritis in England, the phage subtypes of M type 49 streptococci isolated from skin lesions of meat handlers were the same as those recovered from skin lesions of non-meat handlers in the same community.

The findings on the Trinidad isolates suggest that M type 49 streptococci of one phage subtype may persist in a population for 9 years and may result in a second outbreak of acute glomerulonephritis.

In an Alaska Eskimo population in whom acute glomerulonephritis was occurring, most of the M type 49 isolates available for testing were of a single phage subtype. Equally prevalent in this population were group A streptococci that exhibited the same T antigen as the type 49 isolates but differed in their serum opacity reaction and phage subtype. This apparently related strain was not typable with available M antisera but showed functional evidence of M protein and is probably a new M type.

The usefulness of the complement-fixation test in differential diagnosis between vesicular stomatitis and foot-and-mouth disease has been demonstrated on two ‘field’ specimens of virus from Mexico. Examples are given of the practical applications of the other methods for this differential diagnosis.

In March 2018, the US Food and Drug Administration (FDA), US Centers for Disease Control and Prevention, California Department of Public Health, Los Angeles County Department of Public Health and Pennsylvania Department of Health initiated an investigation of an outbreak of Burkholderia cepacia complex (Bcc) infections. Sixty infections were identified in California, New Jersey, Pennsylvania, Maine, Nevada and Ohio. The infections were linked to a no-rinse cleansing foam product (NRCFP), produced by Manufacturer A, used for skin care of patients in healthcare settings. FDA inspected Manufacturer A's production facility (manufacturing site of over-the-counter drugs and cosmetics), reviewed production records and collected product and environmental samples for analysis. FDA's inspection found poor manufacturing practices. Analysis by pulsed-field gel electrophoresis confirmed a match between NRCFP samples and clinical isolates. Manufacturer A conducted extensive recalls, FDA issued a warning letter citing the manufacturer's inadequate manufacturing practices, and federal, state and local partners issued public communications to advise patients, pharmacies, other healthcare providers and healthcare facilities to stop using the recalled NRCFP. This investigation highlighted the importance of following appropriate manufacturing practices to minimize microbial contamination of cosmetic products, especially if intended for use in healthcare settings.