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18 result(s)
Journal Article > ResearchFull Text

Seasonal malaria chemoprevention in a context of high presumed sulfadoxine-pyrimethamine resistance: malaria morbidity and molecular drug resistance profiles in South Sudan

Malar J. 10 November 2023; Volume 22 (Issue 1); 345.; DOI:10.1186/s12936-023-04740-x
Molina-de la Fuente I, Sagrado Benito MJ, Lasry E, Ousley J, García L,  et al.
Malar J. 10 November 2023; Volume 22 (Issue 1); 345.; DOI:10.1186/s12936-023-04740-x
BACKGROUND
Seasonal malaria chemoprevention (SMC) using sulfadoxine-pyrimethamine plus amodiaquine (SP-AQ), is a community-based malaria preventive strategy commonly used in the Sahel region of sub-Saharan Africa. However, to date it has not been implemented in East Africa due to high SP resistance levels. This paper is a report on the implementation of SMC outside of the Sahel in an environment with a high level of presumed SP-resistance: five cycles of SMC using SPAQ were administered to children 3–59 months during a period of high malaria transmission (July–December 2019) in 21 villages in South Sudan.

METHODS
A population-based SMC coverage survey was combined with a longitudinal time series analysis of health facility and community health data measured after each SMC cycle. SMC campaign effectiveness was assessed by Poisson model. SPAQ molecular resistance markers were additionally analysed from dried blood spots from malaria confirmed patients.

RESULTS
Incidence of uncomplicated malaria was reduced from 6.6 per 100 to an average of 3.2 per 100 after SMC administration (mean reduction: 53%) and incidence of severe malaria showed a reduction from 21 per 10,000 before SMC campaign to a mean of 3.3 per 10,000 after each cycle (mean reduction: 84%) in the target group when compared to before the SMC campaign. The most prevalent molecular haplotype associated with SP resistance was the IRNGE haplotype (quintuple mutant, with 51I/59R/108N mutation in pfdhfr + 437G/540E in pfdhps). In contrast, there was a low frequency of AQ resistance markers and haplotypes resistant to both drugs combined (< 2%).

CONCLUSIONS
The SMC campaign was effective and could be used as an additional preventive tool in seasonal malaria settings outside of the Sahel, especially in areas where access to health care is unstable. Malaria case load reduction was observed despite the high level of resistance to SP.
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Journal Article > ResearchFull Text

AmBisome monotherapy and combination AmBisome - miltefosine therapy for the treatment of visceral leishmaniasis in patients co-infected with HIV in India: a randomised open label, parallel arm, phase 3 trial

Clin Infect Dis. 15 October 2022; Volume 75 (Issue 8); 1423-1432.; DOI:10.1093/cid/ciac127
Burza S, Mahajan R, Kazmi S, Alexander N, Kumar D,  et al.
Clin Infect Dis. 15 October 2022; Volume 75 (Issue 8); 1423-1432.; DOI:10.1093/cid/ciac127
BACKGROUND
Visceral leishmaniasis (VL) in patients living with Human-Immunodeficiency-Virus (HIV) present an increasingly important patient cohort in areas where both infections are endemic. Evidence for treatment is sparce, with no high-quality studies from the Indian sub-continent.

METHODS
This is a randomised open label, parallel arm phase-3 trial conducted within a single hospital in Patna, India. 150 patients aged =18 years with serologically confirmed HIV and parasitologically confirmed VL were randomly allocated to one of two treatment arms, either a total 40mg/kg intravenous liposomal amphotericin B(AmBisome) administered in 8 equal doses over 24-days, or a total 30mg/kg intravenous liposomal amphotericin B(AmBisome) administered in 6 equal doses given concomitantly with a total 1.4g oral miltefosine administered through two daily doses of 50mg over 14-days. The primary outcome was ITT relapse-free-survival at day-210, defined as absence of signs and symptoms of VL, or if symptomatic negative parasitological investigations.

FINDINGS
Among 243 patients assessed for eligibility, 150 were recruited between 2nd January 2017 and 5th April 2018, with no loss-to-follow-up. Relapse free survival at day-210 was 85%, (64/75; 95%CI 77-100) in the monotherapy arm, and 96%, (72/75;95%CI 90-100) in the combination arm. 19%(28/150) were infected with concurrent tuberculosis, divided equally between arms. Excluding those with concurrent tuberculosis, relapse free survival at day-210 was 90%, (55/61;95%CI 82-100) in the monotherapy and 97%, (59/61;95%CI 91-100) in the combination therapy arm. Serious adverse events were uncommon and similar in each arm.

CONCLUSIONS
Combination therapy appears to be safe, well tolerated and effective, and halves treatment duration of current recommendations.
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Conference Material > Slide Presentation

Prevalence of asymptomatic Leishmania infection in people living with HIV (PLHIV) and progression to symptomatic visceral leishmaniasis in Bihar, India

Mahajan R, Owen SI, Kumar S, Kazmi S, Das P,  et al.
MSF Scientific Days International 2021: Research. 19 May 2021
Conference Material > Abstract

Prevalence of asymptomatic Leishmania infection in HIV-positive people and progression to symptomatic visceral leishmaniasis in Bihar, India.

Mahajan R, Owen SI, Kumar S, Kazmi S, Das P,  et al.
MSF Scientific Days International 2021: Research. 19 May 2021
INTRODUCTION
People co-infected with visceral leishmaniasis and HIV (VL-HIV) typically present with advanced HIV disease and in poor clinical condition. The reasons for this are complex, but one major challenge relates to difficulties in ensuring early diagnosis of VL, a stage IV opportunistic infection, in the context of HIV. In VL-endemic areas, it is recognised that between 2 and 20% of the general population may harbour asymptomatic Leishmania infection (ALI), the vast majority of whom will not progress to symptomatic disease. However, similar data are absent for people living with HIV (PLHIV) in South Asia. Being able to diagnose ALI may provide a screen-and-treat opportunity to prevent progression to the fatal symptomatic form. We investigated the prevalence and determinants of ALI in PLHIV living in VL-endemic areas, and the risk of progression to symptomatic VL.

METHODS
We conducted a cross-sectional survey, enrolling PLHIV aged ≥18 with no diagnosis of or history of leishmaniasis symptoms, at three antiretroviral therapy centres within VL-endemic regions of Bihar, India. ALI was defined as a positive rK39 enzyme-linked immunosorbent assay (ELISA), rK39 rapid diagnostic test (RDT), and/or quantitative polymerase chain reaction (qPCR) result on blood. In addition, we tested for the Leishmania antigen in urine using ELISA as a novel non-invasive alternative. Participants were followed up at three-monthly intervals over 18 months to assess status and progression to symptomatic infection.

ETHICS
This study was approved by the ethics boards of the Rajendra Memorial Research Institute of Medical Sciences, Patna, India, and Liverpool School of Tropical Medicine, UK, and the MSF Ethics Review Board. Clinical Trial Registry-India number, CTRI/2017/03/008120.

RESULTS
1,296 PLHIV were included in the analysis. The baseline prevalence of ALI was 7.4% (n=96). All were found positive using rK39 ELISA, while 0.5% (n=6) and 0.4% (n=5) were positive using qPCR and rK39 RDT, respectively. 2.2% (n=28) patients were positive using urinary Leishmania antigen ELISA testing. Independent risk factors (p<0.05) for ALI were CD4 count <100 cells/mm3 (adjusted odds ratio, aOR, 3.1; 95%CI 1.2-7.6), and CD4 count between 100-199 cells/mm3 (aOR=2.1; 95%CI 1.1-4.0), as compared to CD4 ≥300 cells/mm3 and living in a household size ≥5 (aOR=1.8; 95%CI 1.1-3.2). Concordance between diagnostic tests was poor. A total of 109 asymptomatic patients were followed up prospectively, including 13 additional patients who were identified during pilot testing. Overall, 3.7% (n=4) patients converted from asymptomatic to symptomatic infection over the study period. Conversion rates of participants identified as positive using rK39 ELISA, rK39 RDT, qPCR, and urinary Leishmania antigen ELISA, were 3.7% (4/109), 40% (2/5), 57% (4/7), and 14% (4/29), respectively. Risk of all-cause mortality in those with ALI over 18 months’ follow-up was 6.4% (n=7), compared with 2.5% (n=30) in those without (risk ratio, 2.6, 95%CI 1.2-5.7, p=0.018).

CONCLUSION
PLHIV living in highly VL-endemic areas have a relatively high prevalence of ALI. Although progression rates to symptomatic infection appear low, all-cause mortality rates are higher and may reflect the impact of sub-clinical infection on HIV outcomes. The results may justify further studies investigating early treatment of ALI in PLHIV.
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Conference Material > Poster

Drivers of antibiotic prescription and use in three MSF projects in Africa

Eibs T, Koscalova A, Jimenez C, Lasry E, Kohler G,  et al.
MSF Scientific Days UK 2019: Research. 30 April 2019; DOI:10.7490/f1000research.1116694.1
Journal Article > ResearchFull Text

The duration of chemoprophylaxis against malaria after treatment with artesunate-amodiaquine and artemether-lumefantrine and the effects of pfmdr1 86Y and pfcrt 76T: a meta-analysis of individual patient data

BMC Med. 25 February 2020; Volume 18 (Issue 1); 47.; DOI:10.1186/s12916-020-1494-3.
Bretscher MT, Dahal P, Griffin J, Stepniewska K, Bassat Q,  et al.
BMC Med. 25 February 2020; Volume 18 (Issue 1); 47.; DOI:10.1186/s12916-020-1494-3.
BACKGROUND
The majority of Plasmodium falciparum malaria cases in Africa are treated with the artemisinin combination therapies artemether-lumefantrine (AL) and artesunate-amodiaquine (AS-AQ), with amodiaquine being also widely used as part of seasonal malaria chemoprevention programs combined with sulfadoxine-pyrimethamine. While artemisinin derivatives have a short half-life, lumefantrine and amodiaquine may give rise to differing durations of post-treatment prophylaxis, an important additional benefit to patients in higher transmission areas.

METHODS
We analyzed individual patient data from 8 clinical trials of AL versus AS-AQ in 12 sites in Africa (n = 4214 individuals). The time to PCR-confirmed reinfection after treatment was used to estimate the duration of post-treatment protection, accounting for variation in transmission intensity between settings using hidden semi-Markov models. Accelerated failure-time models were used to identify potential effects of covariates on the time to reinfection. The estimated duration of chemoprophylaxis was then used in a mathematical model of malaria transmission to determine the potential public health impact of each drug when used for first-line treatment.

RESULTS
We estimated a mean duration of post-treatment protection of 13.0 days (95% CI 10.7-15.7) for AL and 15.2 days (95% CI 12.8-18.4) for AS-AQ overall. However, the duration varied significantly between trial sites, from 8.7-18.6 days for AL and 10.2-18.7 days for AS-AQ. Significant predictors of time to reinfection in multivariable models were transmission intensity, age, drug, and parasite genotype. Where wild type pfmdr1 and pfcrt parasite genotypes predominated (<=20% 86Y and 76T mutants, respectively), AS-AQ provided ~ 2-fold longer protection than AL. Conversely, at a higher prevalence of 86Y and 76T mutant parasites (> 80%), AL provided up to 1.5-fold longer protection than AS-AQ. Our simulations found that these differences in the duration of protection could alter population-level clinical incidence of malaria by up to 14% in under-5-year-old children when the drugs were used as first-line treatments in areas with high, seasonal transmission.

CONCLUSION
Choosing a first-line treatment which provides optimal post-treatment prophylaxis given the local prevalence of resistance-associated markers could make a significant contribution to reducing malaria morbidity.
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Journal Article > ResearchFull Text

Malaria vector control tools in emergency settings: What do experts think? Results from a DELPHI survey

Confl Health. 20 December 2021; Volume 15 (Issue 1); 93.; DOI:10.1186/s13031-021-00424-y
Boete C, Burza S, Lasry E, Moriana S, Robertson W
Confl Health. 20 December 2021; Volume 15 (Issue 1); 93.; DOI:10.1186/s13031-021-00424-y
BACKGROUND
The use and implementation of novel tools for malaria control such as long lasting impregnated bednets (LLINs) and Indoor Residual Spraying (IRS) over the last decade has contributed to a substantial reduction in malaria burden globally. However numerous challenges exist particularly in relation to vector control in emergency settings. This study seeks to explore expert opinion on the utility of existing tools within the emergency context setting and to better understand the attitude towards emerging and innovative tools (including Genetically Modified Mosquitoes) to augment current approaches.

METHODS
80 experts in the field of malaria and vector control were invited to participate in a two-round Delphi survey. They were selected through a combination of literature (academic and policy publications) review and snowball sampling reflecting a range of relevant backgrounds including vector control experts, malaria programme managers and emergency response specialists. The survey was conducted online through a questionnaire including the possibility for free text entry, and concentrated on the following topics: 1. Utility and sustainability of current vector control tools, both in and outside emergency settings 2. Feasibility, utility and challenges of emerging vector control tools, both in and outside emergency settings 3. Current and unmet research priorities in malaria vector control and in malaria control in general.

RESULTS
37 experts completed the first round and 31 completed the second round of the survey. There was a stronger consensus about the increased utility of LLIN compared to IRS in all settings, while insecticide-treated covers and blankets ranked very high only in emergency settings. When considering the combination of tools, the ones deemed most interesting always involved LLINs and IRS regardless of the setting, and the acceptability and the efficacy at reducing transmission are essential characteristics. Regarding perceptions of tools currently under development, consensus was towards improvement of existing tools rather than investing in novel approaches and the majority of respondents expressed distrust for genetic approaches.

CONCLUSION
Malaria vector control experts expressed more confidence for tools whose efficacy is backed up by epidemiological evidence, hence a preference for the improvement rather than the combination of existing tools. Moreover, while several novel tools are under development, the majority of innovative approaches did not receive support, particularly in emergency settings. Stakeholders involved in the development of novel tools should involve earlier and raise awareness of the potential effectiveness amongst a wider range of experts within the malaria community to increase acceptability and improve early adoption once the evidence base is established.
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Journal Article > ResearchFull Text

Seasonal malaria chemoprevention with sulphadoxine-pyrimethamine and amodiaquine selects pfdhfr-dhps quintuple mutant genotype in Mali

PLOS One. 23 September 2016; Volume 11 (Issue 9); e0162718.; DOI:10.1371/journal.pone.0162718
Maiga H, Lasry E, Diarra M, Sagara I, Bamadio A,  et al.
PLOS One. 23 September 2016; Volume 11 (Issue 9); e0162718.; DOI:10.1371/journal.pone.0162718
BACKGROUND
Seasonal malaria chemoprevention (SMC) with sulphadoxine-pyrimethamine (SP) plus amodiaquine (AQ) is being scaled up in Sahelian countries of West Africa. However, the potential development of Plasmodium falciparum resistance to the respective component drugs is a major concern.

METHODS
Two cross-sectional surveys were conducted before (August 2012) and after (June 2014) a pilot implementation of SMC in Koutiala, Mali. Children aged 3-59 months received 7 rounds of curative doses of SP plus AQ over two malaria seasons. Genotypes of P. falciparum Pfdhfr codons 51, 59 and 108; Pfdhps codons 437 and 540, Pfcrt codon 76 and Pfmdr1codon 86 were analyzed by PCR on DNA from samples collected before and after SMC, and in non-SMC patient population as controls (November 2014).

RESULTS
In the SMC population 191/662 (28.9%) and 85/670 (12.7%) of children were P. falciparum positive by microscopy and were included in the molecular analysis before (2012) and after SMC implementation (2014), respectively. In the non-SMC patient population 220/310 (71%) were successfully PCR analyzed. In the SMC children, the prevalence of all molecular markers of SP resistance increased significantly after SMC including the Pfdhfr-dhps quintuple mutant genotype, which was 1.6% before but 7.1% after SMC (p = 0.02). The prevalence of Pfmdr1-86Y significantly decreased from 26.7% to 15.3% (p = 0.04) while no significant change was seen for Pfcrt 76T. In 2014, prevalence of all molecular markers of SP resistance were significantly higher among SMC children compared to the non-SMC population patient (p < 0.01). No Pfdhfr-164 mutation was found neither at baseline nor post SMC.

CONCLUSIONS
SMC increased the prevalence of molecular markers of P. falciparum resistance to SP in the treated children. However, there was no significant increase of these markers of resistance in the general parasite population after 2 years and 7 rounds of SMC.
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Protocol > Research Protocol

A multi-center, open-label trial to compare the efficacy and pharmacokinetics of Artemether-Lumefantrine in children with severe acute malnutrition versus children without severe acute malnutrition: study protocol for the MAL-NUT study

BMC Infect Dis. 12 June 2015; Volume 15 (Issue 1); DOI:10.1186/s12879-015-0963-3
Denoeud-Ndam L, Dicko A, Baudin E, Guindo O, Grandesso F,  et al.
BMC Infect Dis. 12 June 2015; Volume 15 (Issue 1); DOI:10.1186/s12879-015-0963-3
Malnutrition and malaria frequently coexist in sub-Saharan African countries. Studies on efficacy of antimalarial treatments usually follow the WHO standardized protocol in which severely malnourished children are systematically excluded. Few studies have assessed the efficacy of chloroquine, sulfadoxine-pyrimethamine and quinine in severe acute malnourished children. Overall, efficacy of these treatments appeared to be reduced, attributed to lower immunity and for some antimalarials altered pharmacokinetic profiles and lower drug concentrations. However, similar research on the efficacy and pharmacokinetic profiles of artemisinin-combination therapies (ACTs) and especially artemether-lumefantrine in malnourished children is currently lacking. The main objective of this study is to assess whether artemether-lumefantrine is less efficacious in children suffering from severe acute malnutrition (SAM) compared to non-SAM children, and if so, to what extent this can be attributed to a sub-optimal pharmacokinetic profile.More
Protocol > Research Protocol

Prediction of disease severity in young children presenting with acute febrile illness in resource-limited settings: a protocol for a prospective observational study

BMJ Open. 25 January 2021; Volume 11 (Issue 1); e045826.; DOI:10.1136/bmjopen-2020-045826
Chandna A, Aderie EM, Ahmad R, Arguni E, Ashley EA,  et al.
BMJ Open. 25 January 2021; Volume 11 (Issue 1); e045826.; DOI:10.1136/bmjopen-2020-045826
INTRODUCTION
In rural and difficult-to-access settings, early and accurate recognition of febrile children at risk of progressing to serious illness could contribute to improved patient outcomes and better resource allocation. This study aims to develop a prognostic clinical prediction tool to assist community healthcare providers identify febrile children who might benefit from referral or admission for facility-based medical care.

METHODS AND ANALYSIS
This prospective observational study will recruit at least 4900 paediatric inpatients and outpatients under the age of 5 years presenting with an acute febrile illness to seven hospitals in six countries across Asia. A venous blood sample and nasopharyngeal swab is collected from each participant and detailed clinical data recorded at presentation, and each day for the first 48 hours of admission for inpatients. Multianalyte assays are performed at reference laboratories to measure a panel of host biomarkers, as well as targeted aetiological investigations for common bacterial and viral pathogens. Clinical outcome is ascertained on day 2 and day 28.Presenting syndromes, clinical outcomes and aetiology of acute febrile illness will be described and compared across sites. Following the latest guidance in prediction model building, a prognostic clinical prediction model, combining simple clinical features and measurements of host biomarkers, will be derived and geographically externally validated. The performance of the model will be evaluated in specific presenting clinical syndromes and fever aetiologies.

ETHICS AND DISSEMINATION
The study has received approval from all relevant international, national and institutional ethics committees. Written informed consent is provided by the caretaker of all participants. Results will be shared with local and national stakeholders, and disseminated via peer-reviewed open-access journals and scientific meetings.

TRIAL REGISTRATION NUMBER NCT04285021.
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