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Measurements were made of the susceptibility to six commonly prescribed antibiotics, including erythromycin, tetracycline and ciprofloxacin, of 130 isolates of Campylobacterjejuni and 15 isolates of Campylobacter coli cultured from human and poultry sources during 2000. The results were compared with the results from a collection of strains isolated between 1996 and 1998. The levels of resistance to erythromycin remained low, 2 per cent and 4.4 per cent for the human and poultry isolates, respectively. Resistance to tetracycline had increased to 31 per cent and 24.4 per cent from 13.9 per cent and 18.8 per cent for the human and poultry isolates, respectively. However, the resistance to ciprofloxacin of the strains isolated during 2000 had increased to 30 per cent, whereas between 1996 and 1998 there had been no resistance to this agent among human isolates, and only 3.1 per cent resistance among poultry isolates. The molecular basis for this resistance has been shown to be the result of a single amino acid substitution, Thr-86-Ile, in the gyrA subunit of DNA gyrase in Cjejuni. A subset of 59 isolates was tested by molecular methods and all of the 25 phenotypically resistant isolates possessed this substitution. None of the human isolates had been treated with ciprofloxacin before their laboratory isolation.

Shigella sonnei is a significant cause of gastroenteritis in both developing and industrialized countries. Definition of the diversity and antimicrobial susceptibility of S. sonnei isolates may be helpful in the management of individual cases and outbreaks. Antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE) were performed with 67 isolates of S. sonnei predominantly (n ‫؍‬ 59) from three counties in the west of Ireland. Phage typing (n ‫؍‬ 17), plasmid profiling (n ‫؍‬ 28), and integron analysis (n ‫؍‬ 24) were performed with subsets of strains. PFGE typing permitted recognition of two major clusters: PFGE type A (n ‫؍‬ 53) and PFGE type B (n ‫؍‬ 14). PFGE type A was associated with resistance to ampicillin, streptomycin, and sulfonamides (51 of 53 isolates), and those that were phage typed (n ‫؍‬ 6) were phage type 3. PFGE type B was associated with resistance to streptomycin, sulfonamides, tetracycline, and trimethoprim (11 of 14 isolates) and phage type 6 (9 of 11 isolates). Fifteen different plasmid profiles were identified among the 28 isolates analyzed. A class 2 integron was present in all 14 PFGE type B isolates. One of these isolates also contained a class 1 integron and showed a unique variant of the PFGE type B pattern. Sequence analysis of the gene cassette structures contained within these integrons identified distinct open reading frames that encoded determinants of resistance to trimethoprim, streptomycin, and streptothricin. Our data demonstrate two predominant PFGE types among S. sonnei isolates circulating in this region. The limited diversity of the S. sonnei isolates in this region means that detection of isolates indistinguishable by PFGE and according to their antibiograms in two or more patients is not persuasive evidence of a common-source food-or waterborne outbreak. Indistinguishable plasmid profiles in addition to indistinguishable PFGE and antibiogram types may be more suggestive of an epidemiologically relevant link between cases.

Two hundred and thirty fecal specimens were collected from children (up to 5 years of age) admitted with suspected rotaviral gastroenteritis at four Irish hospitals (Cork University Hospital, Mercy Hospital, Cork, Waterford Regional Hospital, and Kerry General Hospital) in the southern region of Ireland, between 2001 and 2004. Following laboratory confirmation of the aetiological agent, the rotavirus G-type was determined in all positive samples by reverse transcriptase-polymerase chain reaction (RT-PCR). The distribution of the G-types (n=230) over the 3 year period was G1 (31%), G9 (21.8%), G3 (8.7%), G4 (6.5%), and G2 (3.5%). There were many mixed infections which accounted for 28.5% of the collection. G9 emerged as the most prevalent G type (30.1%) in 2001-2002, whilst G3 first emerged in 2002-2003 and accounted for 15.8% of the collection. Notably, G2 strains were present at a very low frequency (3.5%) during 2001-2004, compared to an earlier study (1997-1999), where they accounted for 28.5% of the specimens. A smaller subset of the study collection was similarly P-typed (n=139). P[8]-type was identified as the most prevalent P-type, accounting for 97.4% (n=186), while P[4] accounted for just 2.6% (n=5) of the collection. The low frequency of P[4] coincided with the decrease in G2 strains in circulation. The key finding in this study was the emergence of G3- and G9-serotypes as epidemiologically important rotavirus strains since 1999, and the low prevalence of the previously common G2 strains in Ireland. The profile of rotavirus is changing continuously in Ireland and the implications for a successful vaccination program are discussed.

Volume 41, no. 5, p. 1919Volume 41, no. 5, p. -1924. In our paper, we described the characterization of a gene cassette-encoding region from a class 1 integron of Shigella sonnei isolate 1778 and identified a variable cassette region encoding sat-aadA genes. With reference to the letter of Partridge and Hall (J. Clin. Microbiol. 43:4298-4300, 2005), we have revised our sequence data and acknowledge that the sequence we originally identified as sat should be designated estX. Our GenBank entry (accession no. AY090896) has been modified accordingly. 4309on May 11, 2018 by guest