Trends in fluoroquinolone resistance in Campylobacter

Members of the genus Campylobacter remain a leading cause of bacterial gastroenteritis worldwide. Infection is usually self-limiting but in severe cases may require antibiotic treatment. In a recent statement by the World Health Organization (WHO) Campylobacter was named as one of the 12 bacteria that pose the greatest threat to human health because they are resistant to antibiotics. In this mini review we describe recent trends in fluoroquinolone (FQ) (particularly ciprofloxacin) resistance in strains of members of the genus Campylobacter isolated from livestock and clinical samples from several countries. Using evidence from phenotyping surveys and putative resistance prediction from DNA sequence data, we discuss the acquisition and spread of FQ resistance and the role of horizontal gene transfer and describe trends in FQ-resistance in samples from livestock and clinical cases. This review emphasises that FQ resistance remains common among isolates of members of the genus Campylobacter from various sources

Elucidating the aetiology of human Campylobacter coli infections

Peer reviewedPublisher PD

Predicting the onset and persistence of episodes of depression in primary health care. The predictD-Spain study: Methodology

Background: The effects of putative risk factors on the onset and/or persistence of depression remain unclear. We aim to develop comprehensive models to predict the onset and persistence of episodes of depression in primary care. Here we explain the general methodology of the predictD-Spain study and evaluate the reliability of the questionnaires used. Methods: This is a prospective cohort study. A systematic random sample of general practice attendees aged 18 to 75 has been recruited in seven Spanish provinces. Depression is being measured with the CIDI at baseline, and at 6, 12, 24 and 36 months. A set of individual, environmental, genetic, professional and organizational risk factors are to be assessed at each follow-up point. In a separate reliability study, a proportional random sample of 401 participants completed the test-retest (251 researcher-administered and 150 self-administered) between October 2005 and February 2006. We have also checked 118,398 items for data entry from a random sample of 480 patients stratified by province. Results: All items and questionnaires had good test-retest reliability for both methods of administration, except for the use of recreational drugs over the previous six months. Cronbach's alphas were good and their factorial analyses coherent for the three scales evaluated (social support from family and friends, dissatisfaction with paid work, and dissatisfaction with unpaid work). There were 191 (0.16%) data entry errors. Conclusion: The items and questionnaires were reliable and data quality control was excellent. When we eventually obtain our risk index for the onset and persistence of depression, we will be able to determine the individual risk of each patient evaluated in primary health care.The research in Spain was funded by grants from the Spanish Ministry of Health (grant FIS references: PI04/1980, PI0/41771, PI04/2450, and PI06/1442), Andalusian Council of Health (grant references: 05/403, 06/278 and 08/0194), and the Spanish Ministry of Education and Science (grant reference SAF 2006/07192). The Malaga sample, as part of the predictD-International study, was also funded by a grant from The European Commission (reference QL4-CT2002-00683)

Ruminant reservoirs and invertebratevectors for transfer of human pathogens to vegetable crops and ready-to-eat foods

This was a study to determine if invertebrate vectors (i.e. flies and slugs) were able to acquire human pathogens from local ruminant faeces and potentially transfer them to vegetables or ready-to-eat food. A field survey revealed that slugs are able to acquire pathogenic strains of E. coli O.157 that were indistinguishable from those isolated from local sheep faeces. Laboratory experiments demonstrated that commensal E. coli had relatively long survival rates on and in slugs, where the slugs were able to transfer E. coli by direct contact or excretion. Escherichia coli had a slow decline rate in excreted slug faeces with a decimal reduction time of 13.9 days. The results suggest that slugs have the potential to transfer pathogenic E. coli to vegetables. The second part of this work aimed at identifying temporal or host related relationships in the Campylobacter population of cattle and sheep. The Multi-locus sequence typing (MLST) technique was used in addition to quantifying the prevalence and concentrations of Campylobacter excreted by cattle and sheep present on the same farm. Statistically significant temporal variations were identified in addition to differences between the two hosts. During the faecal sampling, flies were also collected. Flies were found to carry identical sequence types (STs) to those present in local ruminant faecal samples. However, despite the relatively low Campylobacter prevalence in flies, certain STs were over represented, suggesting some degree of host restriction. A low number of slugs were also sampled where the Campylobacter ST isolated, had not been identified on this farm or elsewhere. Flies and slugs are able to acquire E. coli O157 and Campylobacter strains, thus posing a potential risk of transfer to vegetable crops.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Temporal Variation and Host Association in the Campylobacter Population in a Longitudinal Ruminant Farm Study▿

Campylobacter jejuni and C. coli were quantified and typed, using multilocus sequence typing (MLST), from fecal samples collected from a mixed cattle and sheep farm during summer. Cattle had a significantly higher prevalence than sheep (21.9% [74/338] and 14.0% [30/214], respectively), but both decreased over time. There were no differences in the average Campylobacter concentrations shed by cattle (600 CFU g−1) and sheep (820 CFU g−1), although sheep did show a significant temporal reduction in the number of Campylobacter organisms shed in their feces. A total of 21 different sequence types (STs) (97.7% C. jejuni, 2.3% C. coli) were isolated from cattle, and 9 different STs were isolated from sheep (40.6% C. jejuni, 59.4% C. coli). The Campylobacter population in cattle was relatively stable, and the frequencies of genotypes isolated showed little temporal variation. However, the composition of subtypes isolated from sheep did show significant temporal differences. The cattle and sheep consistently showed significant differences in their carriage of Campylobacter species, STs, and CCs despite the fact that both were exposed to the same farming environment. This work has highlighted the patterns of a Campylobacter population on a ruminant farm by identifying the existence of both temporal and between-host variations

Results of the logistic regression for the case-case studies.

<p>(A) Odd ratios and their associated P–value for all the selected cases in the univariate models. Factors with P<0.05 are considered as significant (*). Factors with a P<0.25 are entered in the multivariate model (†).</p><p>(B) Odd ratios and p-values for the final multivariate models. Previous steps, consisting in removing one by one the factors with the highest p-Value at each step, are not shown. The program used to execute the analysis gave P = 0.0060 for the overall model fit for the chicken versus non chicken case-case study, and P = 0.0006 for the <i>C. coli</i> versus <i>C. jejuni</i> case-case study. Because gender is the only factor kept at the end of the multivariate model in the chicken versus non chicken study, odd ratio and P-Value are the same as in the univariate gender model.</p>a<p>Animals are grouped into four density groups (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0064504#pone.0064504.s001" target="_blank">File S1</a>) and the odds ratio indicates the relative amount by which the odds of the outcome changes when the value of the predictor value is increased by 1.0 unit.</p

A, ClonalFrame tree of <i>C. coli</i> by host (brown – cattle, green – sheep, pink – pigs, yellow – chicken and red – human clinical.

<p>B, probabilistic assignment of the host of human <i>C. coli</i> infections using structure attribution model (four equal sized columns would be expected in the absence of any genetic differentiation by host). C, Simpson’s index of diversity by host.</p