Household aggregation of cases, one possible characteristic of person-to-person transmitted disease, was formally tested in one epidemic of variola minor by using a pair statistic. A significant result was found for all households as well as for households grouped by the type of environment, or by the phase of the epidemic growth in time. Secondary attack rates, when related to household size (number of susceptibles) showed only a marginal trend in rural households but no trend in urban or semi-rural households.

In operating theatres the air is mainly contaminated with bacteria shed from the human skin. The emission of bacteria can be prevented by wearing clothing of impervious material, while normal cotton clothing does not decrease the shedding of bacteria.

In this study shedding of viable bacteria from 20 test-persons wearing an operating theatre suit, composed of 65% polyester and 35% cotton (Diolen), was investigated in a test-chamber and compared with that when normal clothing was worn. The use of this operating-theatre suit resulted in a significant reduction (50–75%) in the number of bacteria-carrying particles in the air of the test-chamber and in an operating room when everyone present wore this suit. A combination of the suit with knee-high boots showed a further reduction in the dispersal of colony forming units.

The dispersion from female subjects wearing an operating-theatre frock was significantly higher than when wearing an operating-theatre suit.

Seventy-three children under the age of 18 months presenting with acute gastroenteritis were given an electrolyte mixture with added sucrose or glucose in a randomized double-blind trial. The time taken to recovery in those successfully treated as out-patients was identical. However, of the 34 who received glucose, 11 (32%) required admission compared with 7 (18%) of the 39 who received sucrose. There was a wide range of osmolality of the made-up feeds, indicating inaccuracy in diluting the solutions as prescribed, but this did not in general correlate with need for admission.

Sucrose-electrolyte solution is at least as effective as a glucose-electrolyte solution for the out-patient management of acute gastroenteritis in infancy. The cheapness and easy availability of sucrose commends its use in developed and developing countries.

When fresh urine from LCM tolerantly infected mice was applied to small areas of excoriated skin of guinea-pigs undiluted or diluted 10−1, a high LCM infectivity developed in the local dermal tissue within 3 days and quickly spread to the lymphatic system. The skin at this site of infection became erythematous 10–12 days after infection and a few days later a rash was often seen in the hairless skin around the mammary teats. A viraemia was first detected at about 8 days after infection and persisted for at least 8 days, during which time a high infectivity titre in skin not only at the infection site but also distal to it suggested that there was a generalized active infection of the dermis. Infectivity in the tongue was simultaneously high and probably associated with erosions of the tongue tip seen a day or two later than the teat rash.

In similar experiments in hamsters and rabbits, indications were again that lightly injured dermis was a primary site of virus replication. These observations should lead to the dermal route receiving greater attention as a potential route of infection of man when exposed to infectious excretions of reservoir hosts of arena-viruses.

A 14-month survey was undertaken in a diagnostic bacteriology laboratory to determine the incidence of Serratia spp. in routine clinical specimens. Gram-negative organisms with enterobacteria-like colonies were tested by a simple screening procedure. Fifty-eight strains of S. marcescens and two strains of S. liquefaciens were isolated from 59 patients. The strains were usually nonpigmented and exhibited multiple antibiotic resistance. Serotyping and determination of bacteriocine sensitivity patterns revealed that the majority of infections were sporadic, although episodes of cross-infection did occur.

S. marcescens was considered to contribute significantly to morbidity and mortality in 53% of patients and appears to be of increasing importance in hospital-acquired infections.

The results of experiments to investigate antibody to ‘virus infection associated’ (VIA) antigen in cattle repeatedly vaccinated with formalin- or acetylethyleneimine- (AEI) inactivated foot-and-mouth disease (FMD) vaccines under laboratory conditions are reported. Results are also presented from some vaccinated animals subsequently exposed to FMD infection.

Antibody against VIA was not detected before and after the first vaccination with formalin or AEI-inactivated vaccine but did develop in all animals after the second formalin vaccination and persisted throughout the experiment. After the second AEI vaccination, 4 of 12 animals developed antibody which persisted for at least 37 days. This transient response in some cattle was repeated after successive vaccinations but, in general, more animals responded as the number of vaccinations increased.

After exposure to infection, a transient VIA antibody response was occasionally observed in immune AEI-vaccinated animals. Some immune repeatedly AEI-vaccinated cattle did not develop detectable VIA antibody after challenge despite the persistence of virus in oesophageal–pharyngeal (O/P) fluid.

The presence of antibody to VIA antigen is not conclusive proof that vaccinated animals have been exposed to infection and field data must be interpreted with caution.

The anti-haemagglutinin antibody response in adult human volunteers to inactivated whole virus or tween ether split influenza A/Victoria/75 (H3N2) and A/Scotland/74 (H3N2) virus vaccines was investigated using antibody adsorption and single-radial-haemolysis (SRH) techniques. The concentrations of haemagglutinin (HA), nucleoprotein (NP) and matrix (M) antigens measured by single radial diffusion (SRD) and rocket immunoelectrophoresis were similar for both the whole virus and split vaccines. Whole virus and split vaccines induced cross-reactive (CR) antibody in 87% of vaccinees. Strain specific (SS) antibody to A/Hong Kong/1/68 or the homologous virus was induced less frequently than CR antibody. Higher anti-haemagglutinin antibody titres were detected in persons receiving the split virus vaccines than in those receiving the whole virus vaccines. No antibody to the type-specific matrix protein was detectable, but 33% of volunteers developed an antibody rise to type-specific nucleoprotein antigen.

The specificity of the anti-haemagglutinin antibody response in human adults to natural infection with A/Port Chalmers/73 (H3N2) virus was similar to that induced by inactivated vaccines in that a high proportion of subjects developed CR anti-haemagglutinin antibody, which reacted with A/Hong Kong/68 virus and the homologous A/Port Chalmers/73 virus, and SS antibody for A/Hong Kong/68 virus but SS antibody for A/Port Chalmers/73 virus was infrequently stimulated by natural infection.

A collection of 346 strains of Streptococcus milleri from a variety of human sources was examined culturally and biochemically, and for the presence of Lancefield group antigens. Most of the strains were non-haemolytic and ungroupable, but 25% were β haemolytic and 19% were α haemolytic; 28% possessed a group antigen (A, 5%; C, 6%, F, 14%, G, 3%). These antigens were present in 69% of β-haemolytic but in only 13% of α-haemolytic or non-haemolytic strains; β haemolysis occurred in 82% of group-F strains, 43% of other groupable strains and 11% of ungroupable strains.

The following reactions were given by > 80% of S. milleri strains: hydrolysis of arginine and aesculin, a positive Voges–Proskauer reaction, and acidification of trehalose, lactose, salicin and sucrose. A minority of strains showed enhancement of growth by CO2, bile tolerance, NaCl tolerance, and ability to acidify other sugars, notably mannitol, raffinose and melibiose. Departures from the modal pattern of biochemical reactions showed a weak correlation with the type of haemolysis and the presence or absence of a group antigen but were not sufficiently systematic for clear-cut subdivisions to be recognized within the species.

S. milleri therefore appeared to comprise a ‘central’ group of non-haemolytic strains that rarely formed a Lancefield-group antigen, in which the aesculin reaction was nearly always positive, lactose was usually acidified, and a considerable minority showed enhancement of growth by CO2 and bile tolerance. Deviations from this pattern were of two main types. (1) ‘Loss’ of one or more of these reactions, which tended to be associated with β-haemolysis and presence of a group antigen. In these respects, α-haemolytic strains tended to occupy an intermediate position. (2) ‘Gain’ of the ability to acidify additional sugars, notably raffinose and melibiose or mannitol; this occurred mainly among otherwise typical non-haemolytic strains that were rarely groupable.

Only 12% of isolations from the bloodstream of patients suffering from systemic infections were β haemolytic and only 18% possessed a group antigen, but a considerably greater proportion of those from visceral abscesses were β haemolytic (28%). Among isolations from superficial lesions in some body sites there were considerably greater proportions of β-haemolytic and groupable strains; thus, nearly one-half of those isolated from the abdomen other than the female genital tract were β-haemolytic and over one-half were groupable. On the other hand, strains from the teeth and gums were nearly always non-haemolytic and ungroupable, and most vaginal isolations were of non-haemolytic strains with a wide sugar-fermentation pattern.

Re-evaluation of recently published figures comparing the tuberculin Tine Test+ and the Mantoux showed that, contrary to original opinion, the Tine Test+ did perform satisfactorily, the reason for the apparent ineffectiveness lying in the original interpretation of the results.

During the H1N1 outbreak of 1977/8, the virus was isolated in embryonated eggs from 59 out of 76 patients (78%) with the serologically confirmed infection. A similar isolation frequency has been achieved during a period of six H3N2 outbreaks since 1972/3. The H1N1 strains were isolated less frequently from late specimens (collected 4–6 days from the onset of illness) and more often only in the second passage compared with the H3N2 viruses. The new H1N1 strains resembled those prevalent in the 1950s with respect to their ability to agglutinate erythrocytes of certain laboratory animals and to be eluted from these, and thus differed from the H3N2 viruses.

Three detergent preparations (bar soap, ‘Hibiscrub’ base and ‘LIC 76’), two antiseptic preparations (0·5% chlorhexidine in 95% ethyl alcohol and an alcohol jelly, ‘Alcogel’), and one antiseptic-detergent solution (4% chlorhexidine gluconate in a detergent base, ‘Hibiscrub’) were compared for their effectiveness, on a single use, in reducing the yield of bacteria from the hands of volunteers. The antiseptic and antiseptic-detergent preparations were more effective than the detergents, with a mean reduction in yield of skin bacteria of 96·0% after use of alcoholic chlorhexidine and of 81·2% after use of Hibiscrub. One of the detergents, LIC 76, appeared more effective than the others, causing a mean reduction in the yield of skin bacteria of 41·5%, compared with reductions of 4·6% by the Hibiscrub detergent base and an increase of 3·2% with bar soap; unlike the other detergents, LIC 76 was found to have appreciable bacteristatic and bactericidal properties.

Salmonella dublin is primarily adapted to bovines and is a relatively rare cause of human illness. An outbreak is described in which it was estimated that at least 700 persons were infected from milk which had not been subjected to heat treatment. Although the organism was isolated from retail samples of milk, investigations at the dairy farm were inconclusive and a number of questions are posed. Attention is drawn to the value of inter-disciplinary cooperation in the investigation of the outbreak.

The flora of both faeces and small bowel lumen was studied in children with gastroenteritis from London, England, and Kingston, Jamaica.

Clinical and laboratory differences between these two groups are described.

All bacterial groups in the faeces were greatly altered during gastroenteritis and this particularly affected anaerobic organisms. These changes generally reverted rapidly to normal after the illness.

The small bowel flora was also altered during gastroenteritis; there was a tendency for a wider range of organisms including anaerobes to be isolated from the children in Jamaica than from those in England.

The jejunal and stool flora of children with gastroenteritis in London and in Jamaica was examined. Although bacterial colonization of the small bowel was commonly detected, it was unusual to find the same serotype of E. coli in both jejunum and stool, and none of the jejunal strains of E. coli produced either heat-labile or heat-stable enterotoxin. Some strains of E. coli causing infant gastroenteritis are neither toxigenic nor invasive, and other mechanisms must be sought to account for their pathogenicity.

A study was made of the growth of three strains of non-cholera vibrio in a range of foodstuffs and of the effect of temperature and pH on their ability to grow.

Growth was tested at 4°, 10°, 22°, 30°, 37° and 43 °C in a range of foods likely to be incorporated into cold hors d'oeuvres, e.g. egg, cream, rice, cold meat, seafood, aspic and mayonnaise. Non-cholera vibrios grew well in all these foods except mayonnaise, the rate of growth increasing with increased temperature of storage.

At acid pH values the organisms died or grew very poorly but growth improved as the pH became more alkaline. None of the three strains showed any resistance to heat, an initial inoculum of > 107 organisms/g was reduced to < 100 organisms/g in 2–3 mm at 55°C.

During commercial processing of broiler chickens, injection of polyphosphate (Puron 604 or 6040) resulted in microorganisms being added to the deep breast muscle. The level of contamination was related to the microbiological condition of the injection solution.

Injection of polyphosphate had no effect on the shelf-life of fresh chilled carcasses held at 1° or 10°C but changes were observed in the growth rate of microorganisms in the deep muscle and in the composition of the muscle microflora following storage.

Cross-contamination of carcasses and the transfer of organisms from the skin to the deep muscle during injection was demonstrated with a marker strain of Clostridium perfringens. However, both processes were influenced by the number of marker organisms applied initially to the skin.

The above findings are discussed in relation to the possible behaviour of any food poisoning bacteria present.

The distribution of phage types was studied among 577 strains of Salmonella typhi from Indonesia. Chemotype, colicinogeny, and tetrathionate reductase activity were also studied for most of these strains. The current phage type formula for Java was determined to be: A, D2, D6, E1a, E2, M1, and 46, but two other large groups of strains were also found, I +IV and degraded Vi + strains. Significant differences in S. typhi strain distributions were noted between two localities on Java with respect to phage type and tetrathionate reductase activity. Comparisons were made with past phage typing studies in Jakarta as well as with more recent studies in other parts of south-east Asia. Phage types A, Dl, D2, and El persisted at a rather steady level in Jakarta for 28 years. Evidence was found for epidemiological links to European and Asian areas. Antibiotic resistance among these Indonesian S. typhi strains was rare.

The history of the Brown Animal Sanatory Institution was intended originally to be published in book form, and was therefore divided into chapters. For the sake of convenience this division has been continued, even though it is unusual for the term to be employed in scientific periodicals. The history will be published serially in four consecutive issues of the Journal of Hygiene. References have presented a difficulty. In two instances the title of the paper referred to has had to be omitted, because no copy of the original journal in which the article appeared has been obtainable. More important, however, is the failure to give references, beyond the date, to a number of statements in the text, because the information in question has been abstracted from sources that are not available to the general reader.