1,684 research outputs found
Insecticide resistance and the future of malaria control in Zambia.
BACKGROUND: In line with the Global trend to improve malaria control efforts a major campaign of insecticide treated net distribution was initiated in 1999 and indoor residual spraying with DDT or pyrethroids was reintroduced in 2000 in Zambia. In 2006, these efforts were strengthened by the President's Malaria Initiative. This manuscript reports on the monitoring and evaluation of these activities and the potential impact of emerging insecticide resistance on disease transmission. METHODS: Mosquitoes were captured daily through a series of 108 window exit traps located at 18 sentinel sites. Specimens were identified to species and analyzed for sporozoites. Adult Anopheles mosquitoes were collected resting indoors and larva collected in breeding sites were reared to F1 and F0 generations in the lab and tested for insecticide resistance following the standard WHO susceptibility assay protocol. Annual cross sectional household parasite surveys were carried out to monitor the impact of the control programme on prevalence of Plasmodium falciparum in children aged 1 to 14 years. RESULTS: A total of 619 Anopheles gambiae s.l. and 228 Anopheles funestus s.l. were captured from window exit traps throughout the period, of which 203 were An. gambiae malaria vectors and 14 An. funestus s.s.. In 2010 resistance to DDT and the pyrethroids deltamethrin, lambda-cyhalothrin and permethrin was detected in both An. gambiae s.s. and An. funestus s.s.. No sporozoites were detected in either species. Prevalence of P. falciparum in the sentinel sites remained below 10% throughout the study period. CONCLUSION: Both An. gambiae s.s. and An. funestus s.s. were controlled effectively with the ITN and IRS programme in Zambia, maintaining a reduced disease transmission and burden. However, the discovery of DDT and pyrethroid resistance in the country threatens the sustainability of the vector control programme
Tuberculosis among older adults in Zambia: Burden and characteristics among a neglected group
BACKGROUND: The 2010 Global Burden of Disease estimates show that 57% of all TB deaths globally occurred among adults older than 50 years of age. Few studies document the TB burden among older adults in Southern Africa. We focused on adults older than 55 years to assess the relative TB burden and associated demographic factors. METHODS: A cross sectional nationally representative TB prevalence survey conducted of Zambian residents aged 15 years and above from 66 clusters across all the 10 provinces of Zambia. Evaluation included testing for TB as well as an in-depth questionnaire. We compared survey data for those aged 55 and older to those aged 15-54 years. Survey results were also compared with 2013 routinely collected programmatic notification data to generate future hypotheses regarding active and passive case finding. RESULTS: Among older adults with TB, 30/ 54 (55.6%) were male, 3/27 (11.1%) were HIV infected and 35/54 (64.8%) lived in rural areas. TB prevalence was higher in those aged ≥55 (0.7%) than in the 15-54 age group (0.5%). Males had higher rates of TB across both age groups with 0.7% (15-54) and 1.0% (≥55) compared with females 0.4% (15-54) and 0.6% (≥55). In rural areas, the prevalence of TB was significantly higher among older than younger adults (0.7% vs 0.3%), while the HIV infection rate was among TB patients was lower (11.1% vs 30.8%). The prevalence survey detected TB in 54/7484 (0.7%) of older adults compared to 3619/723,000 (0.5% ) reported in 2013 programmatic data. CONCLUSION: High TB rates among older adults in TB endemic areas justify consideration of active TB case finding and prevention strategies
Effect of CdSe quantum dots on hole transport in poly(3-hexylthiophene) thin films
This letter demonstrates the effect of cadmium selenide (CdSe) quantum dots on hole transport in poly(3-hexylthiophene) (P3HT) thin films. Current-voltage characteristics of P3HT and P3HT:CdSe thin films have been studied in the temperature range of 288–85 K, in hole only device configurations, i.e., indium tin oxide (ITO)/poly(ethylene-dioxthiophene):polystyrenesulphonate (PEDOT:PSS)/P3HT/Au and ITO/PEDOT:PSS/P3HT:CdSe/Au. The incorporation of CdSe quantum dots in P3HT results in the enhancement in hole current and switches the transport from dual conduction mechanism, viz., trap and mobility models to only trap model. This is attributed to the reduction in characteristic trap energy from 60 to 32 meV and trap density from 2.5×1018 to 1.7×1018 cm−3
Paediatric malaria case-management with Artemether-Lumefantrine in Zambia: a repeat cross-sectional study
BACKGROUND
Zambia was the first African country to change national antimalarial treatment policy to artemisinin-based combination therapy – artemether-lumefantrine. An evaluation during the early implementation phase revealed low readiness of health facilities and health workers to deliver artemether-lumefantrine, and worryingly suboptimal treatment practices. Improvements in the case-management of uncomplicated malaria two years after the initial evaluation and three years after the change of policy in Zambia are reported. 
METHODS
Data collected during the health facility surveys undertaken in 2004 and 2006 at all outpatient departments of government and mission facilities in four Zambian districts were analysed. The surveys were cross-sectional, using a range of quality of care assessment methods. The main outcome measures were changes in health facility and health worker readiness to deliver artemether-lumefantrine, and changes in case-management practices for children below five years of age presenting with uncomplicated malaria as defined by national guidelines. 
RESULTS. 
In 2004, 94 health facilities, 103 health workers and 944 consultations for children with uncomplicated malaria were evaluated. In 2006, 104 facilities, 135 health workers and 1125 consultations were evaluated using the same criteria of selection. Health facility and health worker readiness improved from 2004 to 2006: availability of artemether-lumefantrine from 51% (48/94) to 60% (62/104), presence of artemether-lumefantrine dosage wall charts from 20% (19/94) to 75% (78/104), possession of guidelines from 58% (60/103) to 92% (124/135), and provision of in-service training from 25% (26/103) to 41% (55/135). The proportions of children with uncomplicated malaria treated  with artemether-lumefantrine also increased from 2004 to 2006: from 1% (6/527) to 27% (149/552) in children weighing 5 to 9 kg, and from 11% (42/394) to 42% (231/547) in children weighing 10 kg or more. In both weight groups and both years, 22% (441/2020) of children with uncomplicated malaria were not prescribed any antimalarial drug. 
CONCLUSION
Although significant improvements in malaria case-management have occurred over two years in Zambia, the quality of treatment provided at the point of care is not yet optimal. Strengthening weak health systems and improving the delivery of effective interventions should remain high priority in all countries implementing new treatment policies for malaria.Zambian-Boston University Malaria Project; Health Systems & Services Project sub-contract to Boston University/CIHD by means of a cooperative agreement with USAID/Zambia (Contract number 690-C-00-04-00153-00); Wellcome Trust U
Removal of ecotoxicity of 17α-ethinylestradiol using TAML/peroxide water treatment
17α -ethinylestradiol (EE2), a synthetic oestrogen in oral contraceptives, is one of many pharmaceuticals found in inland waterways worldwide as a result of human consumption and excretion into wastewater treatment systems. At low parts per trillion (ppt), EE2 induces feminisation of male fish, diminishing reproductive success and causing fish population collapse. Intended water quality standards for EE2 set a much needed global precedent. Ozone and activated carbon provide effective wastewater treatments, but their energy intensities and capital/operating costs are formidable barriers to adoption. Here we describe the technical and environmental performance of a fast- developing contender for mitigation of EE2 contamination of wastewater based upon smallmolecule, full-functional peroxidase enzyme replicas called “TAML activators”. From neutral to basic pH, TAML activators with H2O2 efficiently degrade EE2 in pure lab water, municipal effluents and
EE2-spiked synthetic urine. TAML/H2O2 treatment curtails estrogenicity in vitro and substantially diminishes fish feminization in vivo. Our results provide a starting point for a future process in which tens of thousands of tonnes of wastewater could be treated per kilogram of catalyst. We suggest TAML/H2O2 is a worthy candidate for exploration as an environmentally compatible, versatile, method for removing EE2 and other pharmaceuticals from municipal wastewaters.Heinz Endowments, the Swiss National Science Foundation, the Steinbrenner Institute for a Steinbrenner
Doctoral Fellowship. NMR instrumentation at CMU was partially supported by NSF (CHE-0130903 and
CHE-1039870)
DH Brothers Industries (PTY) Limited vs. Olivine Industries (PTY) Limited (Appeal No. 74/2010) [2012] ZMSC 17
Effect of HIV self-testing on the number of sexual partners among female sex workers in Zambia: A randomized controlled trial
Objectives: To assess the effect of two health system approaches to distribute HIV selftests
on the number of female sex workers’ client and nonclient sexual partners.
Design: Cluster randomized controlled trial.
Methods: Peer educators recruited 965 participants. Peer educator–participant
groups were randomized 1 : 1 : 1 to one of three arms: delivery of HIV self-tests directly
from a peer educator, free facility-based delivery of HIV self-tests in exchange for
coupons, or referral to standard-of-care HIV testing. Participants in all three arms
completed four peer educator intervention sessions, which included counseling and
condom distribution. Participants were asked the average number of client partners
they had per night at baseline, 1 and 4 months, and the number of nonclient partners
they had in the past 12 months (at baseline) and in the past month (at 1 month and
4 months).
Results: At 4 months, participants reported significantly fewer clients per night in the
direct delivery arm (mean difference 0.78 clients, 95% CI 1.28 to 0.28, P ¼ 0.002)
and the coupon arm (0.71, 95% CI 1.21 to 0.21, P ¼ 0.005) compared with
standard of care. Similarly, they reported fewer nonclient partners in the direct delivery
arm (3.19, 95% CI 5.18 to 1.21, P ¼ 0.002) and in the coupon arm (1.84, 95% CI
3.81 to 0.14, P ¼ 0.07) arm compared with standard of care.
Conclusion: Expansion of HIV self-testing may have positive behavioral effects enhancing
other HIV prevention efforts among female sex workers in Zambia.
Trial Registration: ClinicalTrials.gov NCT02827240.
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Genomic epidemiology of Cryptococcus yeasts identifies adaptation to environmental niches underpinning infection across an African HIV/AIDS cohort
Emerging infections caused by fungi have become a widely recognized global phenomenon and are causing an increasing burden of disease. Genomic techniques are providing new insights into the structure of fungal populations, revealing hitherto undescribed fine-scale adaptations to environments and hosts that govern their emergence as infections. Cryptococcal meningitis is a neglected tropical disease that is responsible for a large proportion of AIDS-related deaths across Africa; however, the ecological determinants that underlie a patient's risk of infection remain largely unexplored. Here, we use genome sequencing and ecological genomics to decipher the evolutionary ecology of the aetiological agents of cryptococcal meningitis, Cryptococcus neoformans and Cryptococcus gattii, across the central African country of Zambia. We show that the occurrence of these two pathogens is differentially associated with biotic (macroecological) and abiotic (physical) factors across two key African ecoregions, Central Miombo woodlands and Zambezi Mopane woodlands. We show that speciation of Cryptococcus has resulted in adaptation to occupy different ecological niches, with C. neoformans found to occupy Zambezi Mopane woodlands and C. gattii primarily recovered from Central Miombo woodlands. Genome sequencing shows that C. neoformans causes 95% of human infections in this region, of which over three-quarters belonged to the globalized lineage VNI. We show that VNI infections are largely associated with urbanized populations in Zambia. Conversely, the majority of C. neoformans isolates recovered in the environment belong to the genetically diverse African-endemic lineage VNB, and we show hitherto unmapped levels of genomic diversity within this lineage. Our results reveal the complex evolutionary ecology that underpins the reservoirs of infection for this, and likely other, deadly pathogenic fungi
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