Samples of milk from 1501 cows with mastitis were negative for Campylobacter jejuni. The faeces of 74 healthy Friesian cows were screened for C. jejuni: 13% of the samples were positive during the summer when the cows were on pasture, and 51% were positive in the winter when the cows were housed. Positive samples contained on average 1 × 104 campylobacters per g faeces.

It is concluded that faecal contamination rather than udder infection is the means by which campylobacters enter milk and thereby infect man.

Bacteriocin production (P)-typing of 75 M-type 49 group-A streptococci obtained from a variety of epidemiological incidents in different countries gave no evidence of production under the usual aerobic test conditions. However, with anaerobic incubation, 28% of the strains gave a pattern of inhibitory activity against the indicator strains which was indistinguishable from that previously attributed to the bacteriocin, streptococcin A-FF22 (SA-FF22). Isolation and partial purification of the M type 49 bacteriocin (SA-M49) by freeze–thaw elution from anaerobically grown lawn cultures, followed by ammonium sulphate precipitation and Sephadex chromatography, showed the activity to be associated with a heat-stable proteinaceous molecule of molecular weight approximately 8000 – properties similar to those of SA-FF22. SA-FF22 and SA-M49 were found to have identical inhibitory spectra including immunity of the producer strains to the inhibitory activity of both the homologous and heterologous bacteriocin preparations. SA-M49 production occurred in some strains of phage subtypes II, III and provisional VI and. since it was a consistent property for all isolates from single outbreaks of infection, it provides a means of discriminating between strains of each of these three phage subtypes. There was no evidence of any increased incidence of SA-M49 production in M-type 49 strains associated with nephritic sequelae

Sera from patients with Crohn's disease more often than those from other subjects contain agglutinins against anaerobic coccoid rods, identified as Peptostreptococcus productus, Eubacterium contortum (two strains) and Coprococcus comes. The presence of antigens of the four coccoid rods in faeces of patients with Crohn's disease and healthy subjects was investigated by inoculation of rats with faecal suspensions. Antigens of the coccoid rods were detected in faeces from both patients with Crohn's disease and healthy subjects.

Routine examination of the water system in an establishment where showers were used by staff after work or leisure activities revealed the presence of Legionella pneumophila. Descaling and steaming cleared the system but six months later recolonization was found to have occurred. L. pneumophila was isolated from air samples collected in the shower room whilst the shower was in operation. No clinical cases have occurred. Serological examination of those using the showers throughout the six month period together with a control group showed no evidence of infection.

Klebsiella vaccine was prepared from strains of Klebsiella aerogenes with capsular types Kl, K36, K44 and K Cross (a type which cross-reacts in vitro with sera from many klebsiella capsular types). The vaccine was extracted by dialysis and ultrafiltration from capsular material released during growth of the bacteria in a five-day batch culture.

Mice given one dose of vaccine from K1a (l·0 μg/mouse) survived lethal intraperitoneal challenge of 11/11 homologous klebsiella strains four days after vaccination; 14 days after vaccination protection against the same challenge strains had declined to 5/11 strains. Vaccines from Kla, b, c, K3G, K44 and K Cross induced homologous protection and protected mice against different ranges of heterologous klebsiella capsular types.

The protective response of the mice was greatly enhanced by administering three doses of the vaccines. Vaccines from Kl, K36, K44 and K Cross protected mice against 14/20, 11/20, 10/20 and 9/20 homologous and heterologous klebsiella challenge strains respectively.

None of the klebsiella vaccines was toxic for mice at the immunizing dose (l·0 μg/mouse). Vaccine from K36 was the most lethal, killing mice at 103 immunizing doses. The least toxic vaccine was from K44, which killed mice at 104 immunizing doses.

A study of cleaning and disinfection methods in a variety of types of catering premises has been carried out. The level of bacterial contamination of the hands and of equipment was related to cleaning methods and to the type of catering establishment. Wiping cloths were frequently contaminated with Escherichia coli, and these may be important reservoirs of bacteria for contamination of the hands of catering staff. Regular and efficient cleaning of food surfaces and equipment was found to be more important than the use of a disinfectant as part of the cleaning process. Methods for reducing the risks of cross-contamination in catering premises are discussed.

Thirty six people suffered from severe vomiting and diarrhoea 15 min to 3 h after eating vanilla slices from the same bakery. Five patients were admitted to hospital, and one developed unusual skin lesions after admission. Staphylococcus aureus was isolated in large numbers from vanilla slices of the same batch as those giving rise to symptoms, and from five faecal specimens obtained from affected persons. Bacillus cereus and Bacillus subtilis were also isolated from the slices. Unbaked custard provides an ideal environment for bacterial multiplication, especially when (as on this occasion) the ambient temperature is persistently high.

This investigation was designed to determine the prevalence of Corynebacterium suis in the preputial diverticulum of pigs of various age groups, located in different parts of the U.K., and to demonstrate whether the organism is transmissible between male pigs.

C. suis was isolated from almost 90% of 224 adult males, distributed among 25 pig units in widely separated regions of the country and in 96 % of 66 pigs aged 5–6 months originating from six different herds in East Anglia. The rate of isolation of C. suis from younger pigs depended, at least in part, on the system of husbandry practised. Thus, in one herd, A, in which young pigs were maintained in comparative isolation, none of 26 pigs aged 5–8 weeks harboured C. suis; however, in the same herd, the organism was isolated from 77 % of 64 pigs aged 9–15 weeks which were in close contact with male pigs aged up to 6 months. In another herd, B, in which individual litters were housed in the same pen from birth to 5 months of age, C. suis was isolated once from only one of 36 pigs in the age range 5–17 weeks, sampled on two occasions, with an interval of 5 weeks between each sampling. In a third herd, C, in which adult males had never been present, C. suis was not isolated from any of 26 pigs aged 4 months.

In each of two herds at the Royal Veterinary College colonization of the preputial diverticulum by C. suis was shown to have occurred by the age of 5 weeks in all of 38 pigs examined in a Large White herd and in all of 29 pigs in a Göttingen miniature pig herd.

Transmission experiments clearly demonstrated the ease and rapidity with which the preputial diverticulum became colonized with C. suis when non-infected pigs were placed in close contact with pigs which harboured the organism.

The efficacy of five rodenticides for use in bait against the golden hamster (Mesocricetus auratus Waterhouse) was investigated in the laboratory. The species proved to be resistant to warfarin (up to 0·5%) and difenacoum (0·005%), but brodifacoum (0·005%) gave complete mortality after three days' feeding. Calciferol (0·1%), though toxie, was significantly unpalatable. Zinc phosphide (5·0%) presented in a choice test for two days against unpoisoned feed gave 100% mortality, and appears to be the most suitable of these compounds for the control of M. auratus in the field.