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First report of a mycolactone-producing Mycobacterium infection in fish agriculture in Belgium [research letter]
No full textIn the past few years, a mycolactone-producing subgroup of the Mycobacterium marinum complex has been identified and analyzed. These IS2404-positive species cause pathology in frogs and fish. A recently isolated mycobacterial strain from a fish in Belgium was analyzed using a variety of molecular methods and the results were identical to those obtained from a mycolactone-producing M. marinum from Israel
Rapid detection of multidrug-resistant Mycobacterium tuberculosis in Cotonou (Benin) using two low-cost colorimetric methods: resazurin and nitrate reductase assays
No full textWe have evaluated two simple, rapid and low-cost colorimetric methods for the detection of multidrug-resistant Mycobacterium tuberculosis. A total of 151 M. tuberculosis strains were tested for resistance to rifampicin (RMP) and isoniazid by resazurin microplate assay (REMA) and nitrate reductase assay (NRA) in comparison with the conventional proportion method (PM) on Löwenstein-Jensen medium. A complete agreement was found between NRA and PM, while one false RMP-susceptible result was found by REMA. REMA and NRA tests are rapid and inexpensive, and could be good alternatives to the conventional PM in low-resource countries
Development and application of assays for monitoring drug resistance in HIV-2 infected patients on antiretroviral therapy
No full textMaking HIV prevention programmes work
No full textEven after 25 years of experience, HIV prevention programming remains largely deficient. We identify four areas that managers of national HIV prevention programmes should reassess and hence refocus their efforts-improvement of targeting, selection, and delivery of prevention interventions, and optimisation of funding. Although each area is not wholly independent from one another, and because each country and epidemic context will require a different balance of time and funding allocation in each area, we present the current state of each dimension in the global HIV prevention arena and propose practical ways to remedy present deficiencies. Insufficient data for intervention effectiveness and country-specific epidemiology has meant that programme managers have operated, and continue to operate, in a fog of uncertainty. Although priority must be given to the improvement of prevention methods and the capacity for the generation and use of evidence to improve programme planning and implementation, uncertainty will remain. In the meantime, however, we argue that prevention programming can be made much more effective by use of information that is readily available
A Bayesian evaluation of three diagnostic assays for the detection of Giardia duodenalis in symptomatic and asymptomatic dogs
No full textA Bayesian approach was used to evaluate three commonly used diagnostic assays for the detection of Giardia duodenalis in dogs: microscopical examination (ME), a commercial immunofluorescence assay (IFA: MerifluorGiardia test) and a commercial immunochromatographic assay (SNAP: Idexx SNAPGiardia test). These assays were evaluated for use in two different settings: in a cross-sectional epidemiological survey in household dogs and in a clinical survey, both conducted in the northern part of Belgium. A total of 272 faecal samples from household dogs and 141 faecal samples from clinically affected dogs were examined using these three diagnostic assays. The Bayesian analysis indicated that all tests were highly specific (specificity above 90%), and that the IFA is more sensitive than SNAP and ME, both in an epidemiological and in a clinical setting. For all three tests, the estimated sensitivity values were higher in the clinical compared to the epidemiological survey, whereas the specificity values were comparable in both studies. The results of the present study indicate that IFA is a highly specific and sensitive technique for the detection of G. duodenalis cysts, both for use in an epidemiological or clinical survey. The SNAP is a specific and fairly sensitive technique for the diagnosis of Giardia in clinically affected dogs. Overall, the ME was found to be a specific diagnostic technique, although lacking sensitivity
Male circumcision for HIV prevention in sub-Saharan Africa: who, what and when?
No full textNot the final published versionBACKGROUND AND OBJECTIVE: Male circumcision (circumcision) reduces HIV incidence in men by 50-60%. The United Nations Joint Programme on HIV/AIDS (UNAIDS) recommends the provision of safe circumcision services in countries with high HIV and low circumcision prevalence, prioritizing 12-30 years old HIV-uninfected men. We explore how the population-level impact of circumcision varies by target age group, coverage, time-to-scale-up, level of risk compensation and circumcision of HIV infected men. DESIGN AND METHODS: An individual-based model was fitted to the characteristics of a typical high-HIV-prevalence population in sub-Saharan Africa and three scenarios of individual-level impact corresponding to the central and the 95% confidence level estimates from the Kenyan circumcision trial. The simulated intervention increased the prevalence of circumcision from 25 to 75% over 5 years in targeted age groups. The impact and cost-effectiveness of the intervention were calculated over 2-50 years. Future costs and effects were discounted and compared with the present value of lifetime HIV treatment costs (US$ 4043). RESULTS: Initially, targeting men older than the United Nations Joint Programme on HIV/AIDS recommended age group may be the most cost-effective strategy, but targeting any adult age group will be cost-saving. Substantial risk compensation could negate impact, particularly if already circumcised men compensate. If circumcision prevalence in HIV uninfected men increases less because HIV-infected men are also circumcised, this will reduce impact in men but would have little effect on population-level impact in women. CONCLUSION: Circumcision is a cost-saving intervention in a wide range of scenarios of HIV and initial circumcision prevalence but the United Nations Joint Programme on HIV/AIDS/WHO recommended target age group should be widened to include older HIV-uninfected men and counselling should be targeted at both newly and already circumcised men to minimize risk compensation. To maximize infections-averted, circumcision must be scaled up rapidly while maintaining quality
Rational use of antiretroviral therapy in low-income and middle-income countries: optimizing regimen sequencing and switching
No full textNot the final published versio
Episodic antiretroviral therapy increases HIV transmission risk compared with continuous therapy: results of a randomized controlled trial
No full textNot the final published versionOBJECTIVE: To compare the HIV transmission risk among patients randomized to episodic versus continuous antiretroviral therapy. DESIGN: This was a substudy of the Strategies of Management of Antiretroviral Therapy study, in which patients were randomized to continuous versus CD4-guided episodic antiretroviral therapy. Participants were surveyed about sexual activity and needle sharing and had laboratory testing for gonorrhea, chlamydia, and syphilis. RESULTS: A total of 883 patients were enrolled in this study, the mean age of the patients was 45 years, 25% were women, and 78% were on antiretroviral therapy. At baseline, 136 participants (15.4%) had high-risk behavior (vaginal or anal sex without a condom, needle sharing, or incident bacterial sexually transmitted infection). After randomization, the proportion of participants reporting high-risk behavior was stable and did not differ by randomized arm (P = 0.39). Among participants off therapy at baseline, high-risk behavior was less common 4 months after randomization among those who were randomized to start antiretroviral therapy (P = 0.03). HIV transmission risk (high-risk behavior while HIV RNA level >1500 copies/mL) with partners perceived to be HIV uninfected was higher in the episodic therapy arm (P = 0.02). CONCLUSIONS: Patients on episodic antiretroviral therapy did not decrease high-risk behavior, and because HIV RNA levels were higher, this strategy may result in increased HIV transmission
Occurrence of free-living amoebae in communities of low and high endemicity for Buruli ulcer in southern Benin
No full textBuruli ulcer or Mycobacterium ulcerans disease occurs mainly in areas in proximity to standing or slowly running freshwater, habitats in which free-living amoebae occur. For this reason, a possible link between the habitat of M. ulcerans and free-living amoebae was investigated. Free-living amoebae and mycobacteria were isolated from water and biofilm specimens taken from protected and unprotected sources of water in villages known to have either high or low endemicity for Buruli ulcer in Benin. Amoebae were isolated from 78.8% of samples. A greater proportion of water bodies in areas of high endemicity had amoebae than in areas of low endemicity (83.3% versus 66.7%). Protected sources of water were significantly more likely to contain amoebae in areas of high endemicity than in areas of low endemicity (88.0% versus 11.1%). Several pathogenic free-living amoebae and mycobacteria were isolated. However, no M. ulcerans was isolated and no specimen was positive for IS2404 PCR. Our results show that the study area has a water hygiene problem, which is greater in areas of high Buruli ulcer endemicity than in areas of low endemicity. Our observations indicate that additional studies are required to explore the possible link between free-living amoebae and mycobacteria