Risk factors for antibiotic resistance in Campylobacter spp. isolated from raw poultry meat in Switzerland

BACKGROUND: The world-wide increase of foodborne infections with antibiotic resistant pathogens is of growing concern and is designated by the World Health Organization as an emerging public health problem. Thermophilic Campylobacter have been recognised as a major cause of foodborne bacterial gastrointestinal human infections in Switzerland and in many other countries throughout the world. Poultry meat is the most common source for foodborne cases caused by Campylobacter. Because all classes of antibiotics recommended for treatment of human campylobacteriosis are also used in veterinary medicine, in view of food safety, the resistance status of Campylobacter isolated from poultry meat is of special interest. METHODS: Raw poultry meat samples were collected throughout Switzerland and Liechtenstein at retail level and examined for Campylobacter spp. One strain from each Campylobacter-positive sample was selected for susceptibility testing with the disc diffusion and the E-test method. Risk factors associated with resistance to the tested antibiotics were analysed by multiple logistic regression. RESULTS: In total, 91 Campylobacter spp. strains were isolated from 415 raw poultry meat samples. Fifty-one strains (59%) were sensitive to all tested antibiotics. Nineteen strains (22%) were resistant to a single, nine strains to two antibiotics, and eight strains showed at least three antibiotic resistances. Resistance was observed most frequently to ciprofloxacin (28.7%), tetracycline (12.6%), sulphonamide (11.8%), and ampicillin (10.3%). One multiple resistant strain exhibited resistance to five antibiotics including ciprofloxacin, tetracycline, and erythromycin. These are the most important antibiotics for treatment of human campylobacteriosis. A significant risk factor associated with multiple resistance in Campylobacter was foreign meat production compared to Swiss meat production (odds ratio = 5.7). CONCLUSION: Compared to the situation in other countries, the data of this study show a favourable resistance situation for Campylobacter strains isolated from raw poultry meat produced in Switzerland. Nevertheless, the prevalence of 19% ciprofloxacin resistant strains is of concern and has to be monitored. "Foreign production vs. Swiss production" was a significant risk factor for multiple resistance in the logistic regression model. Therefore, an adequate resistance-monitoring programme should include meat produced in Switzerland as well as imported meat samples

Antimicrobial resistance monitoring in Swiss pork production

An optimized national resistance monitoring program should deliver a precise estimate of the resistance situation for a given combination of bacteria and antimicrobial at a low cost. In order to achieve this, decisions need to be made on the number of samples to be collected at each of different possible sampling points along the food production line.</p

Prevalence of Salmonella in fattening pigs and pork from animal friendly farms

The objective of this project is to compare the prevalence of Salmonella spp, Campylobacter coli/jejuni and Yersinia spp in pigs and in pork from traditional housing systems to new animal friendly systems. On a representative sample of 50 traditional and 50 animal-friendly farms, faecal samples are collected. Faecal culture is performed for all three micro-organisms; isolated strains are further characterised. From a batch of pigs of each farm, meat samples are collected at the slaughterhouse and presence of anti-Salmonella spp antibodies is tested by meat juice analysis. Additionally, fresh pork cuts from animal friendly and conventional production are collected from 300 retailers. Analysis results from farm, slaughterhouse and retail level are compared. The influence of the production systems is assessed using regression analysis, correcting for other possible risk factors. The outcome of this study will be used as a basis for the development of new control strategies for zoonotic pathogens on Swiss fattening farms.</p

Cohort profile of a study on outcomes related to tuberculosis and antiretroviral drug concentrations in Uganda: design, methods and patient characteristics of the SOUTH study

PURPOSE: Tuberculosis (TB) is a leading cause of death among people living with HIV in sub-Saharan Africa. Several factors influence the efficacy of TB treatment by leading to suboptimal drug concentrations and subsequently affecting treatment outcome. The aim of this cohort is to determine the association between anti-TB drug concentrations and TB treatment outcomes. PARTICIPANTS: Patients diagnosed with new pulmonary TB at the integrated TB-HIV outpatient clinic in Kampala, Uganda, were enrolled into the study and started on first-line anti-TB treatment. FINDINGS TO DATE: Between April 2013 and April 2015, the cohort enrolled 268 patients coinfected with TB/HIV ; 57.8% are male with a median age of 34 years (IQR 29-40). The median time between the diagnosis of HIV and the diagnosis of TB is 2 months (IQR 0-22.5). The majority of the patients are antiretroviral therapy naive (75.4%). Our population is severely immunosuppressed with a median CD4 cell count at enrolment of 163 cells/µL (IQR 46-298). Ninety-nine per cent of the patients had a diagnosis of pulmonary TB confirmed by sputum microscopy, Xpert/RIF or culture and 203 (75.7%) have completed TB treatment with 5099 aliquots of blood collected for pharmacokinetic analysis. FUTURE PLANS: This cohort provides a large database of well-characterised patients coinfected with TB/HIV which will facilitate the description of the association between serum drug concentrations and TB treatment outcomes as well as provide a research platform for future substudies including evaluation of virological outcomes. TRIAL REGISTRATION NUMBER: NCT01782950; Pre-results

Delayed Sputum Culture Conversion in Tuberculosis-Human Immunodeficiency Virus-Coinfected Patients With Low Isoniazid and Rifampicin Concentrations

Background The relationship between concentrations of anti-tuberculosis (TB) drugs, sputum conversion and treatment outcome remains unclear. We sought to determine the association between anti-TB drug concentrations and sputum conversion among TB-HIV co-infected patients on first-line anti-TB drugs. Method We enrolled HIV-infected Ugandans with pulmonary TB. Estimation of first-line anti-TB drug concentrations was performed 1, 2, and 4 hours after drug intake at 2, 8, and 24 weeks of TB treatment. Serial sputum cultures were performed at each visit. Time-to-event analysis was used to determine factors associated with sputum culture conversion. Results We enrolled 268 HIV-infected patients. Patients with low isoniazid and rifampicin concentrations were less likely to have sputum culture conversion before the end of TB treatment or by the end of follow-up; Hazard ratio (HR) 0.54: 95% confidence interval (CI): 0.37-0.77, P=0.001 and HR: 0.61, 95% CI: 0.44-0.85, P=0.003, respectively. Patients in the highest AUC quartile for rifampicin and isoniazid were approximately two times more likely to experience sputum conversion. Rifampicin and isoniazid concentrations below the thresholds and being in a weight band <55kg were both risk factors for unfavorable TB treatment outcomes. Only 4.4% of the participants had treatment failure. Conclusion Although low anti-TB drug concentrations did not translate to a high proportion of patients with treatment failure, the association between low concentrations of rifampicin and isoniazid and delayed culture conversion may have implications on TB transmission

Delayed sputum culture conversion in tuberculosis-human immunodeficiency virus-coinfected patients with low isoniazid and rifampicin concentrations

Background. The relationship between concentrations of antituberculosis drugs, sputum culture conversion, and treatment outcome remains unclear. We sought to determine the association between antituberculosis drug concentrations and sputum conversion among patients coinfected with tuberculosis and human immunodeficiency virus (HIV) and receiving first-line antituberculosis drugs. Methods. We enrolled HIV-infected Ugandans with pulmonary tuberculosis. Estimation of first-line antituberculosis drug concentrations was performed 1, 2, and 4 hours after drug intake at 2, 8, and 24 weeks of tuberculosis treatment. Serial sputum cultures were performed at each visit. Time-to-event analysis was used to determine factors associated with sputum culture conversion. Results. We enrolled 268 HIV-infected patients. Patients with low isoniazid and rifampicin concentrations were less likely to have sputum culture conversion before the end of tuberculosis treatment (hazard ratio, 0.54; 95% confidence interval, .37–.77; P = .001) or by the end of follow-up (0.61; .44–.85; P = .003). Patients in the highest quartile for area under the rifampicin and isoniazid concentration-time curves for were twice as likely to experience sputum conversion than those in the lowest quartile. Rifampicin and isoniazid concentrations below the thresholds and weight <55 kg were both risk factors for unfavorable tuberculosis treatment outcomes. Only 4.4% of the participants had treatment failure. Conclusion. Although low antituberculosis drug concentrations did not translate to a high proportion of patients with treatment failure, the association between low concentrations of rifampicin and isoniazid and delayed culture conversion may have implications for tuberculosis transmission