Short report: molecular markers associated with Plasmodium falciparum resistance to sulfadoxine-pyrimethamine in the Democratic Republic of Congo.

Sulfadoxine-pyrimethamine (SP) is the first line antimalarial treatment in the Democratic Republic of Congo. Using polymerase chain reaction, we assessed the prevalence of mutations in the dihydrofolate reductase (dhfr) (codons 108, 51, 59) and dihydropteroate synthase (dhps) (codons 437, 540) genes of Plasmodium falciparum, which have been associated with resistance to pyrimethamine and sulfadoxine, respectively. Four hundred seventy-four patients were sampled in Kilwa (N = 138), Kisangani (N = 112), Boende (N = 106), and Basankusu (N = 118). The proportion of triple mutations dhfr varied between sites but was always > 50%. The proportion of dhps double mutations was < 20%, with some sites as low as 0.9%. A quintuple mutation was present in 12.8% (16/125) samples in Kilwa; 11.9% (13/109) in Kisangani, 2.9% (3/102) in Boende, and 0.9% (1/112) in Basankusu. These results suggest high resistance to pyrimethamine alone or combined with sulfadoxine. Adding artesunate to SP does not seem a valid alternative to the current monotherapy

Spatial targeted vector control is able to reduce malaria prevalence in the highlands of Burundi.

In a highland province of Burundi, indoor residual spraying and long-lasting insecticidal net distribution were targeted in the valley, aiming also to protect the population living on the hilltops. The impact on malaria indicators was assessed, and the potential additional effect of nets evaluated. After the intervention--and compared with the control valleys--children 1-9 years old in the treated valleys had lower risks of malaria infection (odds ratio, OR: 0.55), high parasite density (OR: 0.48), and clinical malaria (OR: 0.57). The impact on malaria prevalence was even higher in infants (OR: 0.14). Using nets did not confer an additional protective effect to spraying. Targeted vector control had a major impact on malaria in the high-risk valleys but not in the less-exposed hilltops. Investment in targeted and regular control measures associated with effective case management should be able to control malaria in the highlands

The role of leadership in people-centred health systems: a sub-national study in The Gambia

Recently, increasing attention has been given to behavioural and relational aspects of the people who both define and shape health systems, placing them at the core. A growing refrain includes the assertion that important decisions determining health system performance, including agenda setting, policy formulation and policy implementation, are made by people. Within this actor-oriented approach, good leadership has been identified as a key contributing factor in health systems strengthening. However, leadership remains ill-defined and under-researched, especially in resource-limited settings, and understanding the links between leadership and health outcomes remains a challenge. We explore the concept and practice of healthcare leadership at sub-national level in a low-income country setting, using a people-centric research methodology. In June and July 2013, 15 in-depth interviews were conducted with key informants in formal healthcare leadership roles across urban, peri-urban and rural settings of The Gambia, West Africa. Participants included the entire spectrum of Regional Health Team (RHT) Directors and Chief Executive Officers of all government hospitals, as well as one clinical officer-in-charge in a secondary-level major health centre. We found reference to several important aspects of, and approaches to, leadership, including (i) setting a clear vision; (ii) engendering shared leadership; and (iii) paying attention to human relations in management. Participants described attending to constituencies in government, international development agencies and civil society, as well as to the populations they serve. By illuminating the multi-polar networks within which these leaders are embedded, and through which they operate, we provide insight into the complex ‘organizational ecology’ of the Gambian health system. There is a need to further research and develop healthcare leadership across all levels, within various political, socio-economic and cultural contexts, in order to better work with a range of health actors and to engage them in identifying and acting upon opportunities for health systems strengthening

Gains in awareness, ownership and use of insecticide-treated nets in Nigeria, Senegal, Uganda and Zambia

Abstract Background In April 2000, the Roll Back Malaria (RBM) "Abuja Summit" set a target of having at least 60% of pregnant women and children under five use insecticide-treated nets (ITNs). Thereafter, programmes were implemented to create demand, reduce taxes and tariffs, spur the commercial market, and reach vulnerable populations with subsidized ITNs. Using national ITN monitoring data from the USAID-sponsored AED/NetMark project, this article examines the extent to which these activities were successful in increasing awareness, ownership, and use of nets and ITNs. Methods A series of surveys with standardized sampling and measurement methods was used to compare four countries at two points in time. Surveys were conducted in 2000 and again in 2004 (Nigeria, Senegal, Zambia) or 2006 (Uganda). They contained questions permitting classification of each net as untreated, ever-treated or currently-treated (an ITN). Household members as well as nets owned were enumerated so that households, household members, and nets could be used as units of analysis. Several measures of net/ITN ownership, plus RBM ITN use indicators, were calculated. The results show the impact of ITN activities before the launch of massive free net distribution programmes. Results In 2000, treated nets were just being introduced to the public, but four to six years later the awareness of ITNs was nearly universal in all countries but Nigeria, where awareness increased from 7% to 60%. By any measure, there were large increases in ownership of nets, especially treated nets, in all countries. All countries but Nigeria made commensurate gains in the proportion of under-fives sleeping under a net/ITN, and in all countries the proportion of pregnant women sleeping under a net/ITN increased greatly. Conclusion A mix of demand creation, a strengthened commercial sector, reduced taxes and tariffs, and programmes making ITNs available at reduced prices resulted in impressive gains in awareness, ownership, and use of nets and ITNs in Nigeria, Senegal, Zambia, and Uganda between 2000 and 2004–2006. None of the countries reached the ambitious Abuja targets for ITN use, but they made substantial progress towards them.</p

Implementing Quantum Gates using the Ferromagnetic Spin-J XXZ Chain with Kink Boundary Conditions

We demonstrate an implementation scheme for constructing quantum gates using unitary evolutions of the one-dimensional spin-J ferromagnetic XXZ chain. We present numerical results based on simulations of the chain using the time-dependent DMRG method and techniques from optimal control theory. Using only a few control parameters, we find that it is possible to implement one- and two-qubit gates on a system of spin-3/2 XXZ chains, such as Not, Hadamard, Pi-8, Phase, and C-Not, with fidelity levels exceeding 99%.Comment: Updated Acknowledgement

Maternal pneumococcal nasopharyngeal carriage and risk factors for neonatal carriage after the introduction of pneumococcal conjugate vaccines in The Gambia.

OBJECTIVES: Pneumococcal nasopharyngeal carriage occurs early in life. However, the role of vertical transmission is not well understood. The aims of this study were to describe carriage among mothers and their newborns, and to assess for risk factors for neonatal carriage. METHODS: In a nested retrospective cohort study, we analysed data from the control arm of a randomized controlled trial conducted in The Gambia 2 to 3 years after introduction of pneumococcal conjugate vaccine (PCV) 13. Nasopharyngeal swabs were collected from 374 women and their newborns on the day of delivery, then 3, 6, 14 and 28 days later. Pneumococci were isolated and serotyped using conventional microbiologic methods. RESULTS: Carriage increased from 0.3% (1/373) at birth to 37.2% (139/374) at day 28 (p <0.001) among neonates and from 17.1% (64/374) to 24.3% (91/374) (p 0.015) among women. In both groups, PCV13 vaccine-type (VT) serotypes accounted for approximately one-third of the pneumococcal isolates, with serotype 19A being the most common VT. Maternal carriage (adjusted odds ratio (OR) = 2.82; 95% confidence interval (CI), 1.77-4.80), living with other children in the household (adjusted OR = 4.06; 95% CI, 1.90-8.86) and dry season (OR = 1.98; 95% CI, 1.15-3.43) were risk factors for neonatal carriage. Over half (62.6%) of the neonatal carriage was attributable to living with other children in the same household. CONCLUSIONS: Three years after the introduction of PCV in The Gambia, newborns are still rapidly colonized with pneumococcus, including PCV13 VT. Current strategies for pneumococcal control in Africa do not protect this age group beyond the herd effect

Maternal colonization with Staphylococcus aureus and Group B streptococcus is associated with colonization in newborns.

OBJECTIVES: Although Staphylococcus aureus and Group B streptococcus (GBS) are major causes of neonatal sepsis in sub-Saharan Africa, it is unclear how these bacteria are transmitted to the neonate. METHODS: In a cohort of 377 Gambian women and their newborns, nasopharyngeal swabs were collected at delivery (day 0), and 3, 6, 14 and 28 days later. Breast milk samples and vaginal swabs were collected from the mother. Staphylococcus aureus and GBS were isolated using conventional microbiological methods. RESULTS: Most women were carriers of S. aureus (264 out of 361 with all samples collected, 73.1%) at some point during follow up and many were carriers of GBS (114 out of 361, 31.6%). Carriage of S. aureus was common in all three maternal sites and GBS was common in the vaginal tract and breast milk. Among newborns, carriage of S. aureus peaked at day 6 (238 out of 377, 63.1%) and GBS at day 3 (39 out of 377, 10.3%). Neonatal carriage of S. aureus at day 6 was associated with maternal carriage in the breast milk adjusted OR 2.54; 95% CI 1.45-4.45, vaginal tract (aOR 2.55; 95% CI 1.32-4.92) and nasopharynx (aOR 2.49; 95% CI 1.56-3.97). Neonatal carriage of GBS at day 6 was associated with maternal carriage in the breast milk (aOR 3.75; 95% CI 1.32-10.65) and vaginal tract (aOR 3.42; 95% CI 1.27-9.22). CONCLUSIONS: Maternal colonization with S. aureus or GBS is a risk factor for bacterial colonization in newborns

Glutaraldehyde-based desensitizers’ influence on bonding performances and dentin enzymatic activity of universal adhesives

Objectives: To evaluate the influence of two glutaraldehyde-based desensitizers (L: GLUMA Desensitizer, Heraeus Kulzer and G: GLUMA Desensitizer PowerGel) prior to the adhesive procedures on microtensile bond strength (μTBS) to dentin and endogenous enzymatic activity. Methods: Noncarious human third molars (N = 48) were cut to expose middle coronal dentin. Six experimental groups were formed according to the dentin pre-treatment (L or G) and the universal adhesives (IBU - iBond universal, Kulzer or AU - Adhese Universal, Ivoclar Vivadent) used in the self-etch mode (n = 8): 1) L/IBU; 2) G/IBU; 3) IBU; 4) L/AU; 5) G/AU; 6) AU. Specimens were cut into sticks and stressed until failure after 24 h (T0) or 1 yr of aging (T12). Additional 4 teeth were used for in situ zymography evaluation and data were statistically analyzed (α = 0.05). Results: Dentin pre-treatment, adhesive and aging statistically influenced bond strength and enzymatic activity (P&lt;0.001). AU demonstrated higher bond strength values than IBU (P&lt;0.001). The L resulted in higher bond strength compared to the G and control groups (P&lt;0.001). aging statistically influenced bonding performance, especially when no dentin pre-treatment was performed (P&lt;0.001). In situ zymography revealed that at baseline the control groups exhibited lower interfacial fluorescence compared to the experimental groups, irrespective of the adhesive used (P&lt;0,001). However, after 1 yr of artificial storage, no differences were found among the groups (P&gt;0.05). Conclusions: : Glutharldeadeyde-based products increased bond strength and determined a stabilization of the adhesive interface over time apparently not related to the MMPs inhibition. Clinical Significance: The results of this in vitro study suggest that the application of glutaraldehyde-based desensitizers prior to the adhesive procedures when associated with universal adhesives could result in increased bond strength and stabilization of the adhesive interface over time

Mass Drug Administration With Dihydroartemisinin-piperaquine and Malaria Transmission Dynamics in The Gambia: A Prospective Cohort Study

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