Cattle and sheep were housed with infected pigs for 11 days. Small amounts of virus were recovered intermittently from the pharynx, milk and rectal swabs of the cattle, but no evidence of subclinical infection was found. Some indication of virus growth in the sheep was obtained in that large amounts of virus were recovered from the pharyngeal region 4 to 7 days after exposure and six of the eight sheep developed significant titres of neutralizing antibody which were maintained in four animals for at least 6 weeks.

Two outbreaks of epidemic vomiting are described. One affected 107 students and staff at a college of education out of a total of 398 persons. The other affected 172 pupils and staff out of 357 at a secondary school. Evidence is presented that in both cases infection was acquired in the dining hall of the institution concerned but no specific item of food was found as a likely cause. The literature is reviewed. Possible mechanisms of spread are suggested.

Previous work showed that on the basis of O serotyping alone of Escherichia coli, the majority of babies acquired the same O serotype as was found in the stools of their respective mothers. Further characterization of the E. coli by H serotyping, determination of their antibiotic resistance and ability to ferment six carbohydrates showed that in the majority of cases the previous results were confirmed. In a minority of cases this further testing showed that the strains were not identical. In some instances a number of strains isolated from the same pair showed different combinations of the markers used.

Seven viruses isolated from outbreaks of swine vesicular disease in various countries between 1966 and 1973 were compared in pigs and infant mice. All produced a similar disease and virus excretion pattern in the pig, although the Italy/66 virus was considerably less virulent than the other viruses. The results of cross neutralization tests of convalescent pig sera and the response of 5-day-old mice to intraperitoneal inoculation indicated minor differences between some viruses. The Italy/66, Hong Kong/71 and France/73 viruses differed from each other and also from the Italy/72, England/72, Austria/73 and Poland/73 group of viruses.

A comparison of twelve strains of Mycoplasma dispar by the metabolism inhibition and indirect haemagglutination tests has shown them to form a serologically homogeneous group of micro-organisms. The twelve strains vary in their haemagglutinating activity against erythrocytes from different animal species, and certain of the strains can be distinguished by the erythrocytes they agglutinate. Haemagglutination may thus provide a method by which certain strains can be typed. The erythrocyte receptor site does not appear to contain sialic acid and is not sensitive to proteolytic enzymes. On the mycoplasma cell two attachment sites have been demonstrated. One, by which it attaches to sheep and bovine erythrocytes, is a protein or contains a protein moiety. The chemical nature of the other attachment site, by which M. dispar attaches to rabbit erythrocytes, is unknown.

The relative acceptance of various plain foods by wild house-mice (Mus musculus L.) was compared in laboratory choice tests. The palatability of glycerine and six oils, each included at 5% in pinhead oatmeal, was compared in a similar manner.

The most favoured food was found to be whole canary seed (Phalaris canariensis). Pinhead oatmeal and wheat were also comparatively well accepted. Glycerine, corn oil, arachis oil and mineral oil were more palatable than either olive, linseed or cod-liver oils.

The results of the choice tests are considered in relation to the use of poison baits for the control of free-living mice.

Children were immunized with a single batch of pertussis vaccine, either adsorbed on aluminium hydroxide or plain. With a primary course of three injections, adsorbed vaccine produced higher titres of pertussis agglutinins in the serum than did plain vaccine. There was no obvious difference in response between those who received the three doses at intervals of 1–2 months, starting at 3–4 months of age, and those in whom the third dose was delayed until about 6 months after the second, but the number of children in each group was small.

Pre- and post-vaccination serum samples from 278 volunteers, who were given live influenza vaccines, were tested by haemagglutination inhibition (HI) and single radial immunodiffusion tests (SRDT) for antibody to influenza A/Hong Kong/1/68 (H3N2) virus envelope antigens. Those with high antibody titres detected in both tests were less frequently infected, and 85% of the 159 infected showed rises by HI and 70% by SRDT. Similarly, 69 pairs were tested for antibody to Hong Kong (N2) neuraminidase by neuraminidase inhibition test (NI) and by SRD tests. Those with high titres in both tests resisted infection and those who were infected showed a rise in antibody detected both by NI and SRD tests. In general, SRDT was less sensitive than HI and NI in detecting antibody and antibody rises, but in some volunteers it did detect antibody rises which were not detected by conventional tests. Because of its simplicity and speed it appeared to be of use in evaluating such vaccines.

The indirect immunofluorescent technique has been used to study the specific immunoglobulin responses in the sera of 63 non-immune adult women who received either Cendehill rubella vaccine subcutaneously, RA27/3 rubella vaccine subcutaneously, or RA27/3 vaccine intranasally. IgG, IgA and IgM antibodies increased virtually simultaneously, starting about 2 weeks after vaccination. IgG antibody appeared in all subjects and reached maximum titres 4–6 weeks after vaccination. The mean IgG titres elicited by the three different methods of vaccination did not differ significantly. IgA and IgM antibodies reached their highest titres between 21 and 28 days after vaccination and then declined to low or undetectable titres within about 9 weeks. The maximum IgA titres observed after intranasal administration of RA27/3 vaccine were significantly higher than those which occurred when the same vaccine was given subcutaneously, but no significant difference in IgM titres was observed. When unfractionated sera were examined IgA antibody was detected in 57 cases (91%) and IgM in 51 (81%). Fluorescent examination of fractions obtained by centrifugation on sucrose density gradients frequently revealed small amounts of IgA and IgM antibody which could not be detected by staining unfractionated serum, and with the inclusion of these results IgA antibody was detected in 61 cases (97%) and IgM in 59 (94%).

When 39 adults with pre-existing serum antibody were challenged with vaccine a definite IgA response was detected in only one subject and in no case was there any evidence of the appearance of IgM antibody.

Nasal antibody, consisting of IgG or IgA or both, was detected in 17 out of 23 non-immune subjects (74%) who received RA27/3 vaccine, either subcutaneously or intranasally. Titres were much lower than those which occur in the natural disease and there was no evidence that nasal antibody was elicited more readily by intranasal than by subcutaneous vaccination.

Infant feeds, to be safe, must be free from potentially pathogenic organisms but not necessarily sterile. In-bottle terminal heating is the preferred means of producing such feeds and the advantages and disadvantages of high and low pressure heating methods, including the effect upon the food value of the feeds, are discussed. The safety of a low pressure method in use in Princess Alexandra Hospital, Harlow is described. The choice of method of provision of safe feeds; terminal heating in a central milk kitchen or obtaining a commercial supply should be decided on economic grounds. Hospitals using such commercial supplies, however, should make provision for training mothers in the hypochlorite method of disinfection of bottles and teats and also ensure that their trainee nurses and midwives still receive adequate instruction in the hygiene of feed preparation.

The four main serotypes of Bordetella pertussis (1, 2, 3; 1, 2; 1, 3; 1) undergo spontaneous variation involving loss or gain of antigen 2 or antigen 3. By serial subculture from single colonies on charcoal-blood-agar medium, we have detected loss-mutations from type 1, 2, 3 to 1, 2 or 1, 3, and from type 1, 2 to type 1. Likewise we have found gain-mutations from type 1 to 1, 2 or 1, 3, and from 1, 2 to 1, 2, 3.

These mutations apparently occur with a high frequency in some strains. Other strains have a lower mutation-rate and are more stable antigenically. We have not detected, by this method, either gain- or loss-mutations from the type 1, 3 strains that we have tested.

These findings offer an explanation for the changes in serotype that occur during the course of a pertussis infection in the child and in the marmoset. They also constitute a warning on the possible antigenic instability of laboratory strains, especially relevant in the production, absorption and testing of diagnostic antisera and in the preparation of pertussis vaccine.

A retrospective study of 258 children admitted to Ruchill Hospital, Glasgow, with croup between 1966 and 1972 indicated that the viruses most frequently associated with the syndrome were parainfluenza types 1 and 3 and influenza A. Most cases were admitted in the late autumn and winter months, with a small peak in May and June. This seasonal distribution mirrored the circulation of the main causative agents in the community, parainfluenza 1 being principally associated with the autumn cases, influenza A the winter cases and parainfluenza 3 the summer cases. Two of these ‘croup associated’ viruses showed regular periodicity, parainfluenza 1 occurring biennially in even years and influenza A in most years. The periodicity of parainfluenza 3 is as yet undetermined.

A fatal case of cutaneous anthrax, presenting many unusual features, is reported. No evidence of occupational or domestic exposure to the risk of infection was found.

In a maternity hospital in which the umbilicus and trunk of healthy newborn infants were treated with 0·33% hexachlorophane dusting powder, the hexachlorophane content of blood was measured in mothers before delivery, in infants' umbilical samples at birth, and at 8 days of age in capillary blood samples. One mother and her baby had rather high blood concentrations of hexachlorophane, probably derived from a toilet preparation used before admission to hospital. Hexachlorophane was absent or barely detectable in the other mothers' blood and in the infants' umbilical blood. The hexachlorophane concentrations in the blood of 8-day-old infants ranged from nil to 0·166 μg./ml. (mean 0·066 μg./ml.). These were much less than the concentrations reported to be toxic in animals.

In a previous trial now reported here, a dusting powder containing chlorhexidine instead of hexachlorophane was found to delay the separation of the umbilical cord.

Outbreaks of epidemic keratoconjunctivitis have occurred among workers in shipyards and other industrial concerns in the West of Scotland in 1956, 1967 and 1971–72. In the most recent episode 220 persons were known to be affected and those mainly involved were shipyard personnel working on the open decks of ships under construction; only a few non-industrial workers were affected. As in previous outbreaks adenovirus type 8 was shown to be the causal organism. It is likely that spread of the virus was probably facilitated in some of the patients by such procedures as first aid measures to remove foreign bodies from the eye. A survey of the family contacts of those affected in 1971–72 revealed that only 2% were secondarily infected. This was probably due to propaganda measures to discourage the use of communal face towels, etc.

Despite close virological surveillance over a period of 6 years of patients attending opthalmic clinics in the West of Scotland, there is as yet no clue to the whereabouts of adenovirus type 8 during interepidemic periods. It is suggested that travellers might be responsible for the introduction of the infection into an area.

A trial of influenza A vaccines in general practice is described. Five hundred and seven subjects were vaccinated with either inactivated monovalent A/Hong Kong vaccine, A/England vaccine or influenza B vaccine as control. Local reactions were noted in 24% and general reactions in 12% of patients. Antibody titres in serum were measured by haemagglutination inhibition (HI) and complement fixation (CF) tests in 465 subjects. The influenza vaccines produced substantial increases in both homologous and heterologous antibodies as measured by the HI test and a comparatively poor response as measured by the CF test. Although clinical influenza was confirmed in only a few cases, there was serological evidence of significant subclinical infection in the control group.