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The names Campylobacter laridis, Enterobacter intermedium, and “Flavobacterium branchiophila” are revised to Campylobacter lari, Enterobacter intermedius, and “Flavobacterium branchiophilum,” respectively, according to Rule 12c of the International Code of Nomenclature of Bacteria.

(2005). First isolation and molecular characterisation of a cryptic plasmid from urease-negative Campylobacter lari. British Journal of Biomedical Science: Vol. 62, No. 3, pp. 137-140.

SUMMARY. A surveillance study for thermophilic Campylobacter spp. in broiler flocks was carried out for the year 1998 in Denmark. The study included examinations of 4286 broiler flocks comprising samples from 57,000 birds. Overall, a flock prevalence of 46.0% was recorded. The species distribution was Campylobacter jejuni 86%, Campylobacter coli 11%, Campylobacter lari 1%, other not further diagnosed species 2%. The prevalence was significantly higher in the period from June to October (3.2 < odds ratio [OR]

SUMMARYThe cultural characteristics of 1220Campylobacterstrains from a variety of sources are described. Forty-two were identified asCampylobacter fetusssp.fetus(Véron & Chatelain, 1973), 1120 as members of theC. jejuni/C. coligroup, and 58 did not conform to any known description. Sixteen of the latter strains had the basic characteristics ofC. fetusbut were atypical in certain other respects. The other 42 strains had the thermophilic characteristics of the jejuni/coli group, but were resistant to nalidixie 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 °C clearly distinguished strains ofC. fetusfrom those of the jejuni/coli and the nalidixie acid-resistant thermophilic (NARTC) groups. Maximum growth temperature was less reliable for this purpose, and 43 °C was found to be better than the traditional 42 °C. By arranging the results of three tests (tolerance to 2,3,5-triphenyltetrazolium chloride, growth at 30·5 and 45·5 °C) serially in the form of a schema comprising nine categories, the jejuni/coli strains fell into two main groups resembling the Institute PasteurC. jejuniandC. colitype strains, but these groups could not be clearly defined owing to the existence of strains with intermediate characteristics.Most of the strains from cattle resembledC. jejuni, whereas those from pigs resembledC. coli; poultry strains occupied a more intermediate position. Strains from man and other animals were of mixed types, but most human strains resembledC. jejunirather thanC. 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.

Ten strains of the nalidixic acid-resistant thermophilicCampylobacter (NARTC) group, of which 2 were isolated from human feces, were compared with 12 reference strains representing various species ofCampylobacter. The NARTC strains were a homogeneous group with respect to their cell morphology and 28 physiological and biochemical characters. All were microaerophilic, motile (amphitrichate), gram-negative, curved, S-shaped or helical rods, and representative strains had mean DNA base compositions of 31 to 32 mol % G+C. Distinctive features of the 10 strains were resistance to nalidixic acid and anaerobic growth in the presence of trimethylamine N-oxide hydrochloride (TMAO). The latter feature may account for the common occurrence of NARTC strains in the fecal contents of seagulls. DNA-DNA hybridizations indicated high (≥76%) base sequence relatedness within the group and low (≤15%) relatedness to other species ofCampylobacter. The 10 strains were classified in the genusCampylobacter but they could not be assigned to any previously defined species. Therefore, a new species, with the nameCampylobacter laridis, is proposed for these 10 strains; the type strain is NCTC 11352.

Campylobacter laridis, a recently described thermophilic Campylobacter species found principally in seagulls, has not previously been linked to illness in humans. Six clinical isolates of this species were referred to the national campylobacter reference laboratory in 1982 and 1983. Each isolate was confirmed by biochemical characterization and by DNA relatedness studies. The six isolates were obtained during an illness: enteritis in four, severe crampy abdominal pain in one, and terminal bacteremia in an immunocompromised host in one. The infections occurred in persons 8 months to 71 years old. Neither the geographic distribution nor the reports of the patients suggest that seagulls played a direct role in the epidemiology of these infections. This potential human enteric pathogen appears to be clinically, epidemiologically, and microbiologically similar to Campylobacter jejuni and may be mistaken for it if nalidixic acid susceptibility screening is not routinely performed.

Urease-positive thermophilic campylobacters were isolated for the first time from the feces of two adults with diarrheal disease and from the appendix of a child with appendicitis. They were identified as Campylobacter laridis by a hybridization dot blot assay. Urease testing should be included in the tests used for the identification of campylobacters at the species level, even for those strains which are not of gastric origin.

A lack of knowledge of naturally occurring pathogens is limiting our ability to use the Antarctic to study the impact human-mediated introduction of infectious microorganisms have on this relatively uncontaminated environment. As no large-scale coordinated effort to remedy this lack of knowledge has taken place, we rely on smaller targeted efforts to both study present microorganisms and monitor the environment for introductions. In one such effort, we isolated Campylobacter species from fecal samples collected from wild birds in the Antarctic Peninsula and the sub-Antarctic island of South Georgia. Indeed, in South Georgia, we found Campylobacter lari and the closely related Campylobacter peloridis, but also distantly related human-associated multilocus sequence types of Campylobacter jejuni. In contrast, in the Antarctic Peninsula, we found C. lari and two closely related species, Campylobacter subantarcticus and Campylobacter volucris, but no signs of human introduction. In fact, our finding of human-associated sequence types of C. jejuni in South Georgia, but not in the Antarctic Peninsula, suggests that efforts to limit the spread of infectious microorganisms to the Antarctic have so far been successful in preventing the introduction of C. jejuni. However, we do not know how it came to South Georgia and whether the same mode of introduction could spread it from there to the Antarctic Peninsula.

The application of polymerase chain reaction (PCR) fingerprinting assays enables discrimination between species and strains of microorganisms. PCR primers aiming at arbitrary sequences in combination with primers directed against the repetitive extragenic palindrome (REP) or enterobacterial repetitive intergenic consensus (ERIC) motifs generate isolate-specific DNA banding patterns. Analysis of these PCR fingerprints obtained for 33 isolates of Campylobacter jejuni, 30 isolates of Campylobacter coli, and 8 isolates of Campylobacter lari revealed that besides generation of isolate-specific fragments, species-specific DNA fragments of identical size were synthesized. It appeared that these DNA fragments could be used as species-specific probes, since they are unique for the pattern which they are deriving from. The probes do not cross-react with amplified DNA originating from a large panel of nonrelated microorganisms. Moreover, these probes displayed species specificity, as they reacted with a single restriction fragment on Southern blots containing DNA from C. jejuni, C. coli, and C. lari and other Campylobacter species. This combination of PCR fingerprinting and probe hybridization results in a highly specific identification assay and provides an example of specific test development without the prior need for DNA sequence information. The principle of the procedure holds great promise for the rapid isolation of DNA probes which, in combination with a general PCR assay, may lead to efficient typing and detection procedures for a multitude of medically important nonviral microorganisms.