Campylobacter bacteraemia in England and Wales, 1981-91.

Routine surveillance of infection in England and Wales detected 394 cases of campylobacter bacteraemia in 11 years. This represented an average incidence of 1.5 per 1000 intestinal campylobacter infections, with a range of 0.3/1000 in children aged 1-4 years to 5.9/1000 in patients aged 65 years or more. Definitive identification of 257 isolates showed that 89% were Campylobacter jejuni or C. coli; other species were C. fetus (8.6%), C. lari (0.8%), C. upsaliensis (0.8%), Helicobacter (Campylobacter) fennelliae (0.8%), and Helicobacter (Campylobacter) cinaedi (0.4%). Most (71%) of the C. jejuni/C. coli bacteraemias were in patients with acute enteritis. Of the patients with C. fetus bacteraemia only 27% had diarrhoea; they were older than patients with C. jejuni or C. coli bacteraemia (54.1 v. 45.9 years) and proportionally more of them were male (M:F ratio 2.7:1 v. 1.9:1); 41% had endovascular pathology or cellulitis. There was a higher proportion of C. jejuni serogroup O 4 (Penner) and O 18 strains among blood than faecal isolates, which suggests that they were unusually serum resistant and/or invasive.

Epidemiology of Campylobacter enteritis.

Campylobacter enteritis is the commonest form of infective diarrhoea in most developed countries of the world. In England and Wales laboratory reports indicate an annual incidence of about 85/100,000, but the true rate is probably nearer 1100/100,000. Measured costs run to many millions of pounds per year. Most infections are sporadic and believed to be foodborne; large outbreaks are infrequent and mostly due to the consumption of raw milk or unchlorinated water. Raw meats and animal products, notably broiler chickens, are the main source of campylobacters in food. A case-control study in the U.S.A., where eating habits are similar to those in Europe, attributed about one-half of human Campylobacter infections to the consumption of chickens. The production of Campylobacter-free chickens is not yet practicable, but considerable progress could be made to this end with sufficient motivation and resources from government and the poultry industry.

Lectin typing of Campylobacter isolates.

Isolates of Campylobacter jejuni, C coli, C fetus and C laridis were tested for agglutination reactions with a panel of five lectins: Arachis hypogaea, Bauhinia purpurea, Solanum tuberosum, Triticum vulgaris and Wisteria floribunda. Twenty three patterns of agglutination (lectin types) were recorded among 376 isolates. Patterns were consistent and reproducible. Only 4.5% of isolates were untypable because of autoagglutination. Some lectin types were found exclusively or predominantly in a species, but others were shared between species. Forty two per cent of C jejuni and 35% of C coli isolates belonged to lectin type 4. There was no apparent correlation between lectin type and serotype; different lectin types were found among strains of single Penner and Lior serotypes. Lectin typing is a simple and economical procedure suitable for use in non-specialist laboratories, either as an adjunct to serogrouping or, after further development, as a sole typing scheme.

A demographic survey of campylobacter, salmonella and shigella infections in England. A Public Health Laboratory Service Survey.

Five laboratories serving a population of 1.5 million participated in a 2-year survey of campylobacter, salmonella and shigella infections in patients suffering from gastrointestinal symptoms. In total, 33,857 faecal specimens were examined of which 5.5% yielded campylobacters, 3.4% salmonellas and 0.8% shigellas; incidence of infection (per 100,000 population per year) was 58, 38 and 9 respectively. Peak incidences occurred at different ages for each organism: campylobacter, 1-4 years (183); salmonella, less than 1 year (181); shigella, 1-4 years (17). There was a secondary peak in campylobacter incidence in patients aged 15-24 years (87), which was not seen with salmonella or shigella infections. By recording the age and sex of all patients submitting faecal specimens, it was shown that sampling rates were disproportionately high in infants aged less than 1 year (12:1 relative to other ages). Thus the percentage of faecal samples positive in infants--in sharp contrast to incidence values--was the lowest of any age group for all three organisms. By taking the numbers of faecal specimens tested as denominators in this way, the highest campylobacter isolation rates were in young adults, with a notable male predominance in the 15-24 year (1.7:1) and 45-54 year (1.6:1) age groups. This male predominance was accentuated during the summer (2.1:1) when incidence was generally high. The maximum percentage isolation recorded by any laboratory was 32.5% in males aged 15-24 years in June. The reasons for this pattern of campylobacter infection are unknown, but the similarity of the results between laboratories and the regularity of the seasonal fluctuations recorded over the last 6 years indicate that the sources and routes of infection are geographically similar and stable, yet different from those of salmonellosis.

Campylobacter enteritis associated with the consumption of free school milk.

A large outbreak of campylobacter enteritis associated with the consumption of free school milk is described. The outbreak had an abrupt onset, and lasted for about 3 weeks; it involved mainly school children in the 2-4 and 5-7 year old age groups. During this period it was established from epidemiological and microbiological data that some 2500 children were infected. The source of the epidemic was almost certainly contaminated milk, although bacteriological proof could not be obtained. Biotyping of isolates was of considerable epidemiological value and showed the involvement of two distinct strains, one of which was dominant. Epidemiological evidence of limited person to person transmission of the infection was obtained; febrile convulsions as a prodromal sign of the illness was recognized for the first time. Strains of Campylobacter jejuni, and samples of patients' serum collected during this outbreak have enabled subsequent studies to be initiated on the serotyping of the responsible organism, on the serological response of patients infected with the organism, and on experimental infection of the bovine udder which demonstrated its potential as a source of C. jejuni in raw milk. A careful search of the literature suggests that this is the largest documented outbreak of campylobacter enteritis.

Campylobacter enteritis in dogs and cats: a 'new' zoonosis.

The subject is introduced by a brief historical resumé and account of campylobacter enterocolitis in man. Published figures on the prevalence of campylobacters in normal dogs and cats show a wide range. It is highest (49% dogs, 45% cats) in immature animals, particularly strays or those living in kennels, and lowest (less than 1.6% dogs and cats) in adult animals living in households. Several studies have shown no significant difference between the prevalence in normal animals and those suffering from diarrhoea, but two surveys did show such a difference. It seems that while most animals are unaffected by infection with campylobacters, a few suffer an illness like that seen in man. Longitudinal studies to determine incidence--as opposed to prevalence--of infection are required. A small proportion of human infections are acquired from dogs. These are usually puppies that are themselves suffering from diarrhoea. Only four infections associated with cats (all kittens with diarrhoea) have been reported. Contact is invariably close and the victims are often small children. The application of simple hygienic measures should prevent such infections.

'1001' Campylobacters: cultural characteristics of intestinal campylobacters from man and animals.

The cultural characteristics of 1220 Campylobacter strains from a variety of sources are described. Forty-two were identified as Campylobacter fetus ssp. fetus (Véron & Chatelain, 1973), 1120 as members of the C. jejuni/C. coli group, and 58 did not conform to any known description. Sixteen of the latter strains had the basic characteristics of C. fetus but were atypical in certain other respects. The other 42 strains had the thermophilic characteristics of the jejuni/coli group, but were resistant to nalidixic acid and had other features in common; it is possible that they represent a new species. They were isolated from 19% of locally caught wild seagulls but only occasionally from other animals and man.Growth at 25 degrees C clearly distinguished strains of C. fetus from those of the jejuni/coli and the nalidixic acid-resistant thermophilic (NARTC) groups. Maximum growth temperature was less reliable for this purpose, and 43 degrees C was found to be better than the traditional 42 degrees C. By arranging the results of three tests (tolerance to 2,3,5-triphenyltetrazolium chloride, growth at 30.5 and 45.5 degrees C) serially in the form of a schema comprising nine categories, the jejuni/coli strains fell into two main groups resembling the Institute Pasteur C. jejuni and C. coli type strains, but these groups could not be clearly defined owing to the existence of strains with intermediate characteristics.Most of the strains from cattle resembled C. jejuni, whereas those from pigs resembled C. coli; poultry strains occupied a more intermediate position. Strains from man and other animals were of mixed types, but most human strains resembled C. jejuni rather than C. coli. The type distribution pattern that most nearly matched that of human indigenous strains was given by a half-and-half mixture of strains from cattle and poultry.