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1.
Malar J ; 23(1): 157, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773567

RESUMO

BACKGROUND: Perennial malaria chemoprevention (PMC) aims to protect children at risk from severe malaria by the administration of anti-malarial drugs to children of defined ages throughout the year. Sulfadoxine-pyrimethamine (SP) has been widely used for chemoprevention in Africa and a child-friendly dispersible tablet formulation has recently become available. METHODS: This qualitative non-interventional observational study was conducted in Benin, Côte d'Ivoire, and Mozambique between February and June 2022. Prototype blister packs, dispensing boxes and job aids designed to support dispersible SP deployment for PMC were evaluated using focus group discussions (FGD) and semi-structured in-depth individual interviews (IDI) with health authorities, health personnel, community health workers (CHWs) and caregivers. The aim was to evaluate knowledge and perceptions of malaria and chemoprevention, test understanding of the tools and identify gaps in understanding, satisfaction, user-friendliness and acceptability, and assess the potential role of CHWs in PMC implementation. Interviews were transcribed and imported to ATLAS.ti for encoding and categorization. Thematic content analysis used deductive and inductive coding with cross-referencing of findings between countries and participants to enrich data interpretation. Continuous comparison across the IDI and FGD permitted iterative, collaborative development of materials. RESULTS: Overall, 106 participants completed IDIs and 70 contributed to FGDs. Malaria was widely recognised as the most common disease affecting children, and PMC was viewed as a positive intervention to support child health. The role of CHWs was perceived differently by the target groups, with caregivers appreciating their trusted status in the community, whereas health authorities preferred clinic-based deployment of PMC by health professionals. Empirical testing of the prototype blister packs, dispensing boxes and job aids highlighted the context-specific expectations of respondents, such as familiar situations and equipment, and identified areas of confusion or low acceptance. A key finding was the need for a clear product identity reflecting malaria. CONCLUSION: Simple modifications profoundly affected the perception of PMC and influenced acceptability. Iterative quantitative investigation resulted in PMC-specific materials suited to the local context and socio-cultural norms of the target population with the aim of increasing access to chemoprevention in children most at risk of severe malaria.


Assuntos
Antimaláricos , Quimioprevenção , Combinação de Medicamentos , Malária , Pirimetamina , Moçambique , Benin , Malária/prevenção & controle , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Quimioprevenção/métodos , Quimioprevenção/estatística & dados numéricos , Humanos , Côte d'Ivoire , Pirimetamina/administração & dosagem , Pirimetamina/uso terapêutico , Sulfadoxina/administração & dosagem , Sulfadoxina/uso terapêutico , Pré-Escolar , Feminino , Masculino , Embalagem de Medicamentos/métodos , Lactente , Criança , Adulto
2.
J Infect ; 88(5): 106144, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574776

RESUMO

OBJECTIVE: The effectiveness of intermittent preventive treatment of malaria in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) is threatened by increasing SP-resistance in Africa. We assessed the level of SP-resistance markers, and the clinical and parasitological effectiveness of IPTp-SP in southern Mozambique. METHODS: P. falciparum infection, antimalarial antibodies and dhfr/dhps SP-resistance mutants were detected by quantitative polymerase chain reaction (qPCR), suspension array technology and targeted deep sequencing, respectively, among 4016 HIV-negative women in Maputo province (2016-2019). Univariate and multivariate regression models were used to assess the association between taking the recommended three or more IPTp-SP doses (IPTp3+) and parasitological and clinical outcomes. RESULTS: 84.3% (3385/4016) women received three or more IPTp-SP doses. The prevalence of quintuple mutants at first antenatal care (ANC) visit was 94.2%. IPTp3+ was associated with a higher clearance rate of qPCR-detected infections from first ANC visit to delivery (adjusted odds ratio [aOR]=5.9, 95% CI: 1.5-33.3; p = 0.012), lower seroprevalence at delivery of antibodies against the pregnancy-specific antigen VAR2CSADBL34 (aOR=0.72, 95% CI: 0.54-0.95; p = 0.022), and lower prevalence of low birth weight deliveries (aOR: 0.61, 95% CI: 0.41-0.90; p = 0.013). CONCLUSION: A sustained parasitological effect of IPTp-SP contributes to the clinical effectiveness of IPTp3+ in areas with high prevalence of SP-resistance markers.


Assuntos
Antimaláricos , Combinação de Medicamentos , Resistência a Medicamentos , Malária Falciparum , Plasmodium falciparum , Pirimetamina , Sulfadoxina , Humanos , Feminino , Sulfadoxina/uso terapêutico , Sulfadoxina/administração & dosagem , Pirimetamina/uso terapêutico , Pirimetamina/administração & dosagem , Gravidez , Antimaláricos/uso terapêutico , Adulto , Malária Falciparum/prevenção & controle , Malária Falciparum/epidemiologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Moçambique/epidemiologia , Adulto Jovem , Complicações Parasitárias na Gravidez/prevenção & controle , Complicações Parasitárias na Gravidez/tratamento farmacológico , Adolescente , Quimioprevenção/métodos
3.
Malar J ; 23(1): 89, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539181

RESUMO

A Stakeholder engagement meeting on the implementation of post-discharge malaria chemoprevention (PDMC) in Benin, Kenya, Malawi, and Uganda was held in Nairobi, Kenya, on 27 September 2023. Representatives from the respective National Malaria Control Programmes, the World Health Organization (WHO) Geneva, Africa Regional and Kenya offices, research partners, non-governmental organizations, and the Medicines for Malaria Venture participated. PDMC was recommended by the WHO in June 2022 and involves provision of a full anti-malarial treatment course at regular intervals during the post-discharge period in children hospitalized with severe anaemia in areas of moderate-to-high malaria transmission. The WHO recommendation followed evidence from a meta-analysis of three clinical trials and from acceptability, delivery, cost-effectiveness, and modelling studies. The trials were conducted in The Gambia using monthly sulfadoxine-pyrimethamine during the transmission season, in Malawi using monthly artemether-lumefantrine, and in Kenya and Uganda using monthly dihydroartemisinin-piperaquine, showing a significant reduction in all-cause mortality by 77% (95% CI 30-98) and a 55% (95% CI 44-64) reduction in all-cause hospital readmissions 6 months post-discharge. The recommendation has not yet been implemented in sub-Saharan Africa. There is no established platform for PDMC delivery. The objectives of the meeting were for the participating countries to share country contexts, plans and experiences regarding the adoption and implementation of PDMC and to explore potential delivery platforms in each setting. The meeting served as the beginning of stakeholder engagement within the PDMC Saves Lives project and will be followed by formative and implementation research to evaluate alternative delivery strategies in selected countries. Meeting highlights included country consensus on use of dihydroartemisinin-piperaquine for PDMC and expansion of the target group to "severe anaemia or severe malaria", in addition to identifying country-specific options for PDMC delivery for evaluation in implementation research. Further exploration is needed on whether the age group should be extended to school-age children.


Assuntos
Anemia , Antimaláricos , Artemisininas , Malária , Criança , Humanos , Antimaláricos/uso terapêutico , Quênia , Uganda , Assistência ao Convalescente , Malaui , Benin , Alta do Paciente , Participação dos Interessados , Artemeter/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Malária/prevenção & controle , Malária/tratamento farmacológico , Pirimetamina/uso terapêutico , Combinação de Medicamentos , Quimioprevenção , Anemia/tratamento farmacológico
4.
Am J Trop Med Hyg ; 110(4): 677-680, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38460198

RESUMO

Unlike praziquantel, artemisinin derivatives are effective against juvenile schistosome worms. We assessed the efficacy and safety of a single oral dose of artesunate plus sulfalene-pyrimethamine versus praziquantel in the treatment of Schistosoma mansoni. Seventy-three schoolchildren (aged 9-15 years) with confirmed S. mansoni infection in Rarieda, western Kenya, were randomly assigned to receive either a single oral dose of artesunate plus sulfalene-pyrimethamine (n = 39) or a single dose of praziquantel (n = 34). The cure and egg reduction rates at 4 weeks posttreatment were 69.4% (25/36) versus 80.6% (25/31) (P = 0.297) and 99.1% versus 97.5% (P = 0.607) in the artesunate plus sulfalene-pyrimethamine group versus praziquantel group, respectively. Fourteen children developed adverse events, and there were no serious adverse events. A single oral dose of artesunate plus sulfalene-pyrimethamine has efficacy comparable to that of praziquantel in the treatment of S. mansoni, but these results should be confirmed in larger randomized controlled trials.


Assuntos
Anti-Helmínticos , Artemisininas , Esquistossomose mansoni , Sulfaleno , Criança , Animais , Humanos , Praziquantel/efeitos adversos , Artesunato/uso terapêutico , Schistosoma mansoni , Quênia , Sulfaleno/farmacologia , Sulfaleno/uso terapêutico , Pirimetamina/uso terapêutico , Artemisininas/efeitos adversos , Quimioterapia Combinada , Esquistossomose mansoni/tratamento farmacológico , Resultado do Tratamento , Anti-Helmínticos/uso terapêutico
5.
Antimicrob Agents Chemother ; 68(4): e0153423, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38411062

RESUMO

Malaria remains a leading cause of morbidity and mortality in Burkina Faso, which utilizes artemether-lumefantrine as the principal therapy to treat uncomplicated malaria and seasonal malaria chemoprevention with monthly sulfadoxine-pyrimethamine plus amodiaquine in children during the transmission season. Monitoring the activities of available antimalarial drugs is a high priority. We assessed the ex vivo susceptibility of Plasmodium falciparum to 11 drugs in isolates from patients presenting with uncomplicated malaria in Bobo-Dioulasso in 2021 and 2022. IC50 values were derived using a standard 72 h growth inhibition assay. Parasite DNA was sequenced to characterize known drug resistance-mediating polymorphisms. Isolates were generally susceptible, with IC50 values in the low-nM range, to chloroquine (median IC5010 nM, IQR 7.9-24), monodesethylamodiaquine (22, 14-46) piperaquine (6.1, 3.6-9.2), pyronaridine (3.0, 1.3-5.5), quinine (50, 30-75), mefloquine (7.1, 3.7-10), lumefantrine (7.1, 4.5-12), dihydroartemisinin (3.7, 2.2-5.5), and atovaquone (0.2, 0.1-0.3) and mostly resistant to cycloguanil (850, 543-1,290) and pyrimethamine (33,200, 18,400-54,200), although a small number of outliers were seen. Considering genetic markers of resistance to aminoquinolines, most samples had wild-type PfCRT K76T (87%) and PfMDR1 N86Y (95%) sequences. For markers of resistance to antifolates, established PfDHFR and PfDHPS mutations were highly prevalent, the PfDHPS A613S mutation was seen in 19% of samples, and key markers of high-level resistance (PfDHFR I164L; PfDHPS K540E) were absent or rare (A581G). Mutations in the PfK13 propeller domain known to mediate artemisinin partial resistance were not detected. Overall, our results suggest excellent susceptibilities to drugs now used to treat malaria and moderate, but stable, resistance to antifolates used to prevent malaria.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Falciparum , Malária , Criança , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Plasmodium falciparum , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Combinação Arteméter e Lumefantrina/uso terapêutico , Antagonistas do Ácido Fólico/farmacologia , Burkina Faso , Artemeter/uso terapêutico , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Malária/tratamento farmacológico , Lumefantrina/farmacologia , Lumefantrina/uso terapêutico , Combinação de Medicamentos , Polimorfismo Genético/genética , Resistência a Medicamentos/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/uso terapêutico
6.
BMC Public Health ; 24(1): 43, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166711

RESUMO

BACKGROUND: The uptake of Intermittent Preventive Treatment of malaria in pregnancy using Sulfadoxine-Pyrimethamine (IPTp-SP) remains unacceptably low, with more than two-thirds of pregnant women in sub-Saharan Africa still not accessing the three or more doses recommended by the World Health Organisation (WHO). In contrast, the coverage of Seasonal Malaria Chemoprevention (SMC), a more recent strategy recommended by the WHO for malaria prevention in children under five years living in Sahelian countries with seasonal transmission, including Mali and Burkina-Faso, is high (up to 90%). We hypothesized that IPTp-SP delivery to pregnant women through SMC alongside antenatal care (ANC) will increase IPTp-SP coverage, boost ANC attendance, and increase public health impact. This protocol describes the approach to assess acceptability, feasibility, effectiveness, and cost-effectiveness of the integrated strategy. METHODS AND ANALYSIS: This is a multicentre, cluster-randomized, implementation trial of IPTp-SP delivery through ANC + SMC vs ANC alone in 40 health facilities and their catchment populations (20 clusters per arm). The intervention will consist of monthly administration of IPTp-SP through four monthly rounds of SMC during the malaria transmission season (July to October), for two consecutive years. Effectiveness of the strategy to increase coverage of three or more doses of IPTp-SP (IPTp3 +) will be assessed using household surveys and ANC exit interviews. Statistical analysis of IPT3 + and four or more ANC uptake will use a generalized linear mixed model. Feasibility and acceptability will be assessed through in-depth interviews and focus group discussions with health workers, pregnant women, and women with a child < 12 months. DISCUSSION: This multicentre cluster randomized implementation trial powered to detect a 45% and 22% increase in IPTp-SP3 + uptake in Mali and Burkina-Faso, respectively, will generate evidence on the feasibility, acceptability, effectiveness, and cost-effectiveness of IPTp-SP delivered through the ANC + SMC channel. The intervention is designed to facilitate scalability and translation into policy by leveraging existing resources, while strengthening local capacities in research, health, and community institutions. Findings will inform the local national malaria control policies. TRIAL REGISTRATION: Retrospectively registered on August 11th, 2022; registration # PACTR202208844472053. Protocol v4.0 dated September 04, 2023. Trail sponsor: University of Sciences Techniques and Technologies of Bamako (USTTB), Mali.


Assuntos
Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Criança , Feminino , Gravidez , Humanos , Pré-Escolar , Estações do Ano , Antimaláricos/uso terapêutico , Burkina Faso , Mali , Sulfadoxina/uso terapêutico , Pirimetamina/uso terapêutico , Malária/prevenção & controle , Malária/tratamento farmacológico , Combinação de Medicamentos , Complicações Parasitárias na Gravidez/prevenção & controle , Quimioprevenção , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
7.
Am J Trop Med Hyg ; 110(1): 20-31, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38081050

RESUMO

Seasonal malaria chemoprevention (SMC) for children under 5 years of age for up to four monthly cycles during malaria transmission season was recommended by the WHO in 2012 and has been implemented in 13 countries in the Sahel, reaching more than 30 million children annually. Malaria control programs implementing SMC have asked the WHO to consider expanding the age range or number of monthly cycles. We conducted a systematic review and meta-analysis of SMC among children up to 15 years of age and up to six monthly cycles. Twelve randomized studies were included, with outcomes stratified by age (< 5/≥ 5 years), by three or four versus five or six cycles, and by drug where possible. Drug regimens included sulfadoxine-pyrimethamine + amodiaquine, amodiaquine-artesunate, and sulfadoxine-pyrimethamine + artesunate. Included studies were all conducted in Sahelian countries in which high-grade resistance to sulfadoxine-pyrimethamine was rare and in zones with parasite prevalence ranging from 1% to 79%. Seasonal malaria chemoprevention resulted in substantial reductions in uncomplicated malaria incidence measured during that transmission season (rate ratio: 0.27, 95% CI: 0.25-0.29 among children < 5 years; rate ratio: 0.27, 95% CI: 0.25-0.30 among children ≥ 5 years) and in the prevalence of malaria parasitemia measured within 4-6 weeks from the final SMC cycle (risk ratio: 0.38, 95% CI: 0.34-0.43 among children < 5 years; risk ratio: 0.23, 95% CI: 0.11-0.48 among children ≥ 5 years). In high-transmission zones, SMC resulted in a moderately reduced risk of any anemia (risk ratio: 0.77, 95% CI: 0.72-0.83 among children < 5 years; risk ratio: 0.70, 95% CI: 0.52-0.95 among children ≥ 5 years [one study]). Children < 10 years of age had a moderate reduction in severe malaria (risk ratio: 0.53, 95% CI: 0.37-0.76) but no evidence of a mortality reduction. The evidence suggests that in areas in which sulfadoxine-pyrimethamine and amodiaquine remained efficacious, SMC effectively reduced malaria disease burden among children both < 5 and ≥ 5 years old and that the number of cycles should be commensurate with the length of the transmission season, up to six cycles.


Assuntos
Antimaláricos , Malária , Criança , Pré-Escolar , Humanos , Amodiaquina/uso terapêutico , Antimaláricos/uso terapêutico , Artesunato/uso terapêutico , Quimioprevenção/métodos , Combinação de Medicamentos , Malária/epidemiologia , Malária/prevenção & controle , Malária/tratamento farmacológico , Pirimetamina/uso terapêutico , Estações do Ano , Sulfadoxina/uso terapêutico , Adolescente
8.
Infect Disord Drug Targets ; 24(2): e201023222469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37881078

RESUMO

BACKGROUND: The concern about the global spread of resistant malaria has made the researchers not focus only on the treatment of established infections but relatively more on the prevention of the disease. OBJECTIVE: This study evaluates the chemopreventive activity of ketoconazole in a murine malarial model. METHOD: Five out of seven groups of mice were pretreated for five days with proguanil (PRG), sulfadoxine/ pyrimethamine (SP), 10, 20, and 40 mg/kg body weight (b.w) of ketoconazole (KET10, KET20, and KET40), before being infected (on the sixth day) with Plasmodium berghei. Two other groups were infected-not-treated (INT) and not-infected-nor-treated (NINT). At 72 hours postinfection, five out of ten mice in each group were sacrificed to assess parasitemia, chemoprevention, hematologic, hepatic, and renal parameters. The remaining mice were observed for 28 days to determine their mean survival day post-infection (SDPI). RESULTS: All ketoconazole groups, except KET10, demonstrated 100% chemoprevention and significantly higher mean SDPI (p<0.001) in relation to INT (negative control). There was no significant difference in the mean SDPI observed in KET20 in relation to PRG or NINT (healthy control). A dose-related increase (p<0.01) in the mean plasma urea was observed when ketoconazole groups were compared to one another: KET10 versus KET20 (p<0.01) and KET20 versus KET40 (p<0.01). Sulfadoxine/pyrimethamine demonstrated significantly reduced mean plasma urea (p<0.001) and creatinine (p<0.05) in relation to INT and NINT, respectively. While PRG demonstrated significantly higher mean red blood cell (RBC), hemoglobin (HGB), and hematocrit (HCT) in relation to INT. CONCLUSION: Ketoconazole possesses prophylactic antimalarial activity with associated dose-related renal impairment. Sulfadoxine/pyrimethamine demonstrated renoprotective potentials, while PRG prevented malaria-associated anemia.


Assuntos
Anemia , Antimaláricos , Malária Falciparum , Malária , Animais , Camundongos , Pirimetamina/uso terapêutico , Proguanil/uso terapêutico , Sulfadoxina/uso terapêutico , Cetoconazol/uso terapêutico , Antimaláricos/uso terapêutico , Malária/complicações , Malária/tratamento farmacológico , Malária/prevenção & controle , Anemia/tratamento farmacológico , Anemia/prevenção & controle , Rim , Ureia/uso terapêutico
9.
Redox Biol ; 67: 102901, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37776708

RESUMO

OBJECTIVE: NRF2 is a master transcription factor that regulates the stress response. NRF2 is frequently mutated and activated in human esophageal squamous cell carcinoma (ESCC), which drives resistance to chemotherapy and radiation therapy. Therefore, a great need exists for NRF2 inhibitors for targeted therapy of NRF2high ESCC. DESIGN: We performed high-throughput screening of two compound libraries from which hit compounds were further validated in human ESCC cells and a genetically modified mouse model. The mechanism of action of one compound was explored by biochemical assays. RESULTS: Using high-throughput screening of two small molecule compound libraries, we identified 11 hit compounds as potential NRF2 inhibitors with minimal cytotoxicity at specified concentrations. We then validated two of these compounds, pyrimethamine and mitoxantrone, by demonstrating their dose- and time-dependent inhibitory effects on the expression of NRF2 and its target genes in two NRF2Mut human ESCC cells (KYSE70 and KYSE180). RNAseq and qPCR confirmed the suppression of global NRF2 signaling by these two compounds. Mechanistically, pyrimethamine reduced NRF2 half-life by promoting NRF2 ubiquitination and degradation in KYSE70 and KYSE180 cells. Expression of an Nrf2E79Q allele in mouse esophageal epithelium (Sox2CreER;LSL-Nrf2E79Q/+) resulted in an NRF2high phenotype, which included squamous hyperplasia, hyperkeratinization, and hyperactive glycolysis. Treatment with pyrimethamine (30 mg/kg/day, p.o.) suppressed the NRF2high esophageal phenotype with no observed toxicity. CONCLUSION: We have identified and validated pyrimethamine as an NRF2 inhibitor that may be rapidly tested in the clinic for NRF2high ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/terapia , Neoplasias Esofágicas/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Hiperplasia , Linhagem Celular Tumoral , Proliferação de Células
10.
Malar J ; 22(1): 213, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474966

RESUMO

BACKGROUND: Artemisinin-based combinations therapy (ACT) is the current frontline curative therapy for uncomplicated malaria in Burkina Faso. Sulfadoxine-pyrimethamine (SP) is used for the preventive treatment of pregnant women (IPTp), while SP plus amodiaquine (SP-AQ) is recommended for children under five in seasonal malaria chemoprevention (SMC). This study aimed to assess the proportions of mutations in the P. falciparum multidrug-resistance 1 (Pfmdr1), P. falciparum chloroquine resistance transporter (Pfcrt), P. falciparum dihydrofolate reductase (pfdhfr), and P. falciparum dihydropteroate synthase (pfdhps), genes from isolates collected during household surveys in Burkina Faso. METHODS: Dried blood spots from Plasmodium falciparum-positive cases at three sites (Orodara, Gaoua, and Banfora) collected during the peak of transmission were analysed for mutations in Pfcrt (codons 72-76, 93, 97, 145, 218, 343, 350 and 353), Pfmdr-1 (codons 86, 184, 1034, 1042 and 1246) dhfr (codons 51, 59, 108, 164) and dhps (at codons 431, 436, 437, 540, 581, 613) genes using deep sequencing of multiplexed Polymerase chaine reaction (PCR) amplicons. RESULTS: Of the 377 samples analysed, 346 (91.7%), 369 (97.9%), 368 (97.6%), and 374 (99.2%) were successfully sequenced for Pfcrt, Pfmdr-1, dhfr, and dhps, respectively. Most of the samples had a Pfcrt wild-type allele (89.3%). The 76T mutation was below 10%. The most frequent Pfmdr-1 mutation was detected at codon 184 (Y > F, 30.9%). The single mutant genotype (NFSND) predominated (66.7%), followed by the wild-type genotype (NYSND, 30.4%). The highest dhfr mutations were observed at codon 59R (69.8%), followed by codons 51I (66.6%) and 108 N (14.7%). The double mutant genotype (ACIRSI) predominated (52.4%). For mutation in the dhps gene, the highest frequency was observed at codon 437 K (89.3%), followed by codons 436 A (61.2%), and 613 S (14.4%). The double mutant genotype (IAKKAA) and the single mutant genotype (ISKKAA) were predominant (37.7% and 37.2%, respectively). The most frequent dhfr/dhps haplotypes were the triple mutant ACIRSI/IAKKAA (23%), the wild-type ACNCSI/ISKKAA (19%) and the double mutant ACIRSI/ISKKAA (14%). A septuple mutant ACIRNI/VAKKGA was observed in 2 isolates from Gaoua (0.5%). CONCLUSION: The efficacy of ACT partner drugs and drugs used in IPTp and SMC does not appear to be affected by the low proportion of highly resistant mutants observed in this study. Continued monitoring, including molecular surveillance, is critical for decision-making on effective treatment policy in Burkina Faso.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Humanos , Criança , Feminino , Gravidez , Plasmodium falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Burkina Faso , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malária Falciparum/tratamento farmacológico , Malária/tratamento farmacológico , Mutação , Tetra-Hidrofolato Desidrogenase/genética , Combinação de Medicamentos , Resistência a Medicamentos/genética , Códon
11.
Sci Rep ; 13(1): 7359, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147353

RESUMO

Little is known about the existence of drug-resistant Toxoplasma gondii strains and their possible impact on clinic outcomes. To expand our knowledge about the existence of natural variations on drug susceptibility of T. gondii strains in Brazil, we evaluated the in vitro and in vivo susceptibility to sulfadiazine (SDZ) and pyrimethamine (PYR) of three atypical strains (Wild2, Wild3, and Wild4) isolated from free-living wild birds. In vitro susceptibility assay showed that the three strains were equally susceptible to SDZ and PYR but variations in the susceptibility were observed to SDZ plus PYR treatment. Variations in the proliferation rates in vitro and spontaneous conversion to bradyzoites were also accessed for all strains. Wild2 showed a lower cystogenesis capacity compared to Wild3 and Wild4. The in vivo analysis showed that while Wild3 was highly susceptible to all SDZ and PYR doses, and their combination, Wild2 and Wild4 showed low susceptibility to the lower doses of SDZ or PYR. Interestingly, Wild2 presented low susceptibility to the higher doses of SDZ, PYR and their combination. Our results suggest that the variability in treatment response by T. gondii isolates could possibly be related not only to drug resistance but also to the strain cystogenesis capacity.


Assuntos
Antiprotozoários , Toxoplasma , Sulfadiazina/farmacologia , Sulfadiazina/uso terapêutico , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Antiprotozoários/uso terapêutico , Brasil
12.
Malar J ; 22(1): 145, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37127633

RESUMO

BACKGROUND: Intermittent Preventive Treatment of malaria in infants (IPTi) is a malaria control strategy consisting of the administration of an anti-malarial drug alongside routine immunizations. So far, this is being implemented nationwide in Sierra Leone only. IPTi has been renamed as Perennial Malaria Chemoprevention -PMC-, accounting for its recently recommended expansion into the second year of life. Before starting a pilot implementation on PMC, the currently implemented strategy and malaria prevalence were assessed in young children in selected areas of Sierra Leone. METHODS: A cross-sectional, community-based, multi-stage cluster household survey was conducted from November to December 2021 in selected districts of the Northern and northwestern provinces of Sierra Leone among 10-23 months old children, whose caretakers gave written informed consent to participate in the survey. Coverage of IPTi and malaria prevalence-assessed with rapid diagnostic tests-were calculated using percentages and 95% confidence intervals weighted for the sampling design and adjusted for non-response within clusters. Factors associated with RDT + and iPTi coverage were also assessed. RESULTS: A total of 720 children were recruited. Coverage of three IPTi doses was 50.57% (368/707; 95% CI 45.38-55.75), while prevalence of malaria infection was 28.19% (95% CI 24.81-31.84). Most children had received IPTi1 (80.26%, 574/707; 95% CI 75.30-84.44), and IPTi2 (80.09%, 577/707; 95% CI 76.30-83.40) and over half of the children also received IPTi3 (57.72%, 420/707; 95% CI 53.20-62.11). The uptake of each IPTi dose was lower than that of the vaccines administered at the same timepoint at all contacts. CONCLUSION: In Sierra Leone, half of the children received the three recommended doses of IPTi indicating an increase in its uptake compared to previous data of just a third of children receiving the intervention. However, efforts need to be made in improving IPTi coverage, especially in the planned expansion of the strategy into the second year of life following recent WHO guidelines.


Assuntos
Malária , Pirimetamina , Criança , Humanos , Lactente , Pré-Escolar , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Estudos Transversais , Serra Leoa , Combinação de Medicamentos , Malária/prevenção & controle
13.
Sci Rep ; 13(1): 6311, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072433

RESUMO

Following integrated malaria control interventions, malaria burden on the Bijagós Archipelago has significantly decreased. Understanding the genomic diversity of circulating Plasmodium falciparum malaria parasites can assist infection control, through identifying drug resistance mutations and characterising the complexity of population structure. This study presents the first whole genome sequence data for P. falciparum isolates from the Bijagós Archipelago. Amplified DNA from P. falciparum isolates sourced from dried blood spot samples of 15 asymptomatic malaria cases were sequenced. Using 1.3 million SNPs characterised across 795 African P. falciparum isolates, population structure analyses revealed that isolates from the archipelago cluster with samples from mainland West Africa and appear closely related to mainland populations; without forming a separate phylogenetic cluster. This study characterises SNPs associated with antimalarial drug resistance on the archipelago. We observed fixation of the PfDHFR mutations N51I and S108N, associated with resistance to sulphadoxine-pyrimethamine, and the continued presence of PfCRT K76T, associated with chloroquine resistance. These data have relevance for infection control and drug resistance surveillance; particularly considering expected increases in antimalarial drug use following updated WHO recommendations, and the recent implementation of seasonal malaria chemoprevention and mass drug administration in the region.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Falciparum , Malária , Humanos , Plasmodium falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Guiné-Bissau , Filogenia , Proteínas de Protozoários/genética , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Malária/parasitologia , Mutação , Resistência a Medicamentos/genética , Combinação de Medicamentos , Dinâmica Populacional
14.
BMJ Glob Health ; 8(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37076197

RESUMO

INTRODUCTION: Coverage of antenatal iron and folic acid (IFA) supplementation and malaria chemoprophylaxis remains low in many low-income and middle-income settings. We assessed the effectiveness of personal information (INFO) sessions and personal information session plus home deliveries (INFO+DELIV) to increase coverage of IFA supplementation and intermittent preventive treatment in pregnancy (IPTp), and their effectiveness on postpartum anaemia and malaria infection. METHODS: We included 118 clusters randomised to a control (39), INFO (39) and INFO+DELIV (40) arm, in a trial conducted between 2020 and 2021 with pregnant women (age ≥15 years) in their first or second trimester of pregnancy in Taabo, Côte d'Ivoire. We used generalised linear regression models to assess intervention impact in postpartum anaemia and malaria parasitaemia, and displayed resulting estimates as prevalence ratios. RESULTS: Overall, 767 pregnant women were enrolled and 716 (93.3%) were followed up after delivery. Neither intervention had an impact on postpartum anaemia, with estimated adjusted prevalence ratios (aPRs) of 0.97 (95% CI 0.79 to 1.19, p=0.770) for INFO and 0.87 (95% CI 0.70 to 1.09, p=0.235) for INFO+DELIV. While INFO had no effect on malaria parasitaemia (aPR=0.95, 95% CI 0.39 to 2.31, p=0.915), INFO+DELIV reduced malaria parasitaemia by 83% (aPR=0.17, 95% CI 0.04 to 0.75, p=0.019). No improvements in antenatal care (ANC) coverage (aPR=1.05, 95% CI 0.81 to 1.36, p=0.692), IFA (aPR=2.00, 95% CI 0.89 to 4.46, p=0.093) and IPTp (aPR=1.03, 95% CI 0.87 to 1.21, p=0.728) compliance were found for INFO. INFO+DELIV increased ANC attendance (aPR=1.35, 95% CI 1.02 to 1.78, p=0.037) and compliance with IPTp (aPR=1.60, 95% CI 1.41 to 1.80, p<0.001) and IFA recommendations (aPR=7.06, 95% CI 3.68 to 13.51, p<0.001). CONCLUSIONS: INFO+DELIV can substantially increase compliance with IFA supplementation and improve malaria prevention. However, the increases in IFA supplementation are likely insufficient to address the prevalence of often severe anaemia in this population. TRIAL REGISTRATION NUMBER: NCT04250428.


Assuntos
Anemia , Malária , Gravidez , Feminino , Humanos , Adolescente , Sulfadoxina/uso terapêutico , Pirimetamina/uso terapêutico , Ferro , Côte d'Ivoire/epidemiologia , Combinação de Medicamentos , Malária/epidemiologia , Malária/prevenção & controle , Ácido Fólico/uso terapêutico , Anemia/epidemiologia , Anemia/prevenção & controle , Anemia/tratamento farmacológico , Suplementos Nutricionais
15.
Expert Opin Drug Deliv ; 20(2): 301-311, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36639201

RESUMO

OBJECTIVES: The focus of the present research is to develop printlet formulations of pyrimethamine (PMT). METHODS: Printlets formulation of PMT were developed by screening design by varying laser scanning speed, Kollidon® VA 64, polyvinylpyrrolidone, and disintegrant. RESULTS: Laser scanning speed, Kollidon® VA, and disintegrant had statistically significant effect on hardness, disintegration time, and/or dissolution (p < 0.05). Dissolution was almost 100% in 30 min. X-ray powder diffraction indicated partial amorphous transformation of the crystalline drug. Pharmacokinetic and anti-toxoplasma activity profiles of the printlets and compressed tablets were superimposable with no statistical difference (p > 0.05). CONCLUSION: Clinical performance of the printlets would be similar to the compressed tablets.


Assuntos
Toxoplasma , Toxoplasmose , Humanos , Criança , Pirimetamina/uso terapêutico , Povidona , Excipientes/química , Comprimidos/química , Solubilidade
16.
Exp Parasitol ; 246: 108460, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36642299

RESUMO

Chronic toxoplasmosis which is positively correlated with many neuropsychiatric problems has no curative treatment till now; due to the resistant tissue cysts especially in the brain. In search of an effective treatment, guanabenz-loaded polyethylene glycol poly lactic-co-glycolic acid (PEG-PLGA) nanoparticles was evaluated against chronic experimental toxoplasmosis. For this purpose, each mouse was infected with 10 cysts of Toxoplasma gondii (ME 49 strain). Treated mice received either guanabenz alone (5 mg/kg/day) in subgroup IIa or guanabenz-loaded nanoparticles by full dose in subgroup IIb or guanabenz-loaded nanoparticles by the half dose (2.5 mg/kg/day) in subgroup IIc. Subgroup Ie was treated by pyrimethamine and sulfadiazine. The treatment started on day 25 post-infection for 19 successive days. Then Parasitological, histopathological, immunohistochemical, immunological and ultrastructural morphological studies were performed. The results showed that: subgroup IIb showed the highest statistically significant reduction in the neuroinflammation and brain tissue cysts (77%) with a significant higher efficacy in comparison with pyrimethamine and sulfadiazine and showed the highest level of IFN-γ, while the lowest level was in subgroup IIa. All group II mice showed similar changes of depression and compression of the wall of the cyst. This is marked in subgroup IIb with release of crescent shaped bradyzoite outside the cyst. PEG-PLGA nanoparticles had no toxic effect on the liver or the kidney of the mice. It could be concluded that guanabenz-loaded PEG-PLGA nanoparticles could be promising and safe for treatment of chronic toxoplasmosis.


Assuntos
Guanabenzo , Nanopartículas , Toxoplasma , Toxoplasmose , Animais , Camundongos , Guanabenzo/farmacologia , Guanabenzo/uso terapêutico , Nanopartículas/uso terapêutico , Pirimetamina/uso terapêutico , Pirimetamina/farmacologia , Sulfadiazina/uso terapêutico , Sulfadiazina/farmacologia , Toxoplasmose/tratamento farmacológico
17.
J Antimicrob Chemother ; 78(3): 665-668, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36611259

RESUMO

BACKGROUND: A new mutation in the Plasmodium falciparum dihydropteroate synthetase gene (pfdhps), I431V, has been identified in several countries of Central and West Africa. This mutation is mostly found in association with four other SNPs on pfdhps (S436A, A437G, A581G and A613S), forming a quintuple mutant (vagKgs) and almost always associated with the Plasmodium falciparum dihydrofolate reductase gene (pfdhfr) CirnI (C50R, N51I, S108N) triple mutant. To date, nothing is known about the impact of this new pfdhps genotype on sulfadoxine-pyrimethamine (SP) resistance. OBJECTIVES: We sought to assess the prevalence of this pfdhps vagKgs quintuple mutant in two groups of pregnant women with malaria, one that took intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) and one that did not. METHODS: The pfdhfr and pfdhps genes from Plasmodium falciparum isolates collected in Yaoundé (Cameroon) from pregnant women with symptomatic malaria under IPTp-SP or not, were sequenced. RESULTS: Of 159 patients evaluated, 70 had already taken SP during pregnancy and 89 had never taken SP. Only the vagKgs allele was significantly overrepresented in the SP+ group (21.4% versus 3.4%; P < 0.001), whereas the ISgKAA mutant, widely distributed in this area and known to be less susceptible to SP, tended to be less abundant in this group (48.6% versus 64.0%; P = 0.0503). CONCLUSIONS: We found a strong overrepresentation of the CirnI/vagKgs haplotype in the IPTp-SP pregnant group, suggesting a high level of resistance of this mutant to SP. This could compromise not only the effectiveness of IPTp-SP but also the seasonal malaria chemoprevention of young children, now widely implemented.


Assuntos
Antimaláricos , Malária Falciparum , Pirimetamina , Sulfadoxina , Criança , Pré-Escolar , Feminino , Humanos , Gravidez , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Camarões , Quimioprevenção/métodos , Di-Hidropteroato Sintase/genética , Combinação de Medicamentos , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Mutação , Plasmodium falciparum/genética , Gestantes , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico
18.
Lancet Infect Dis ; 23(3): 361-370, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36328000

RESUMO

BACKGROUND: Seasonal malaria chemoprevention is used in 13 countries in the Sahel region of Africa to prevent malaria in children younger than 5 years. Resistance of Plasmodium falciparum to seasonal malaria chemoprevention drugs across the region is a potential threat to this intervention. METHODS: Between December, 2015, and March, 2016, and between December, 2017, and March, 2018, immediately following the 2015 and 2017 malaria transmission seasons, community surveys were done among children younger than 5 years and individuals aged 10-30 years in districts implementing seasonal malaria chemoprevention with sulfadoxine-pyrimethamine and amodiaquine in Burkina Faso, Chad, Guinea, Mali, Nigeria, Niger and The Gambia. Dried blood samples were collected and tested for P falciparum DNA by PCR. Resistance-associated haplotypes of the P falciparum genes crt, mdr1, dhfr, and dhps were identified by quantitative PCR and sequencing of isolates from the collected samples, and survey-weighted prevalence and prevalence ratio between the first and second surveys were estimated for each variant. FINDINGS: 5130 (17·5%) of 29 274 samples from 2016 and 2176 (7·6%) of 28 546 samples from 2018 were positive for P falciparum on quantitative PCR. Among children younger than 5 years, parasite carriage decreased from 2844 of 14 345 samples (19·8% [95% CI 19·2-20·5]) in 2016 to 801 of 14 019 samples (5·7% [5·3-6·1]) in 2018 (prevalence ratio 0·27 [95% CI 0·24-0·31], p<0·0001). Genotyping found no consistent evidence of increasing prevalence of amodiaquine resistance-associated variants of crt and mdr1 between 2016 and 2018. The dhfr haplotype IRN (consisting of 51Ile-59Arg-108Asn) was common at both survey timepoints, but the dhps haplotype ISGEAA (431Ile-436Ser-437Gly-540Glu-581Ala-613Ala), crucial for resistance to sulfadoxine-pyrimethamine, was always rare. Parasites carrying amodiaquine resistance-associated variants of both crt and mdr1 together with dhfr IRN and dhps ISGEAA occurred in 0·05% of isolates. The emerging dhps haplotype VAGKGS (431Val-436Ala-437Gly-540Lys-581Gly-613Ser) was present in four countries. INTERPRETATION: In seven African countries, evidence of a significant reduction in parasite carriage among children receiving seasonal malaria chemoprevention was found 2 years after intervention scale-up. Combined resistance-associated haplotypes remained rare, and seasonal malaria chemoprevention with sulfadoxine-pyrimethamine and amodiaquine is expected to retain effectiveness. The threat of future erosion of effectiveness due to dhps variant haplotypes requires further monitoring. FUNDING: Unitaid.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Criança , Humanos , Plasmodium falciparum , Amodiaquina/uso terapêutico , Haplótipos , Antimaláricos/uso terapêutico , Estações do Ano , Prevalência , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Combinação de Medicamentos , Quimioprevenção , Nigéria , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/uso terapêutico , Genômica , Resistência a Medicamentos/genética
19.
Clin Infect Dis ; 76(4): 600-608, 2023 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-36219705

RESUMO

BACKGROUND: Malaria in pregnancy has been associated with worse cognitive outcomes in children, but its association with behavioral outcomes and the effectiveness of malaria chemoprevention on child neurodevelopment are not well characterized. METHODS: To determine if more effective malaria chemoprevention in mothers and their children results in better neurodevelopment, 305 pregnant women were randomly assigned to 3 doses of sulfadoxine-pyrimethamine, 3 doses of dihydroartemisinin-piperaquine (DP), or monthly DP during pregnancy, and their 293 children were assigned to DP every 3 months or monthly DP from 2 to 24 months of age. Cognition, language, and motor function were assessed at 12, 24. and 36 months of age, and attention, memory, behavior, and executive function were assessed at 24 and 36 months of age. RESULTS: Children of mothers with versus without malaria in pregnancy had worse scores on cognitive, behavioral, and executive function outcomes at 24 months. Clinical malaria in children within the first 12 months was similarly associated with poorer scores in behavior and executive function at 24 months, language at 24 and 36 months, and motor function scores at 36 months. However, more effective malaria chemoprevention in the mothers and children was not associated with better outcomes. CONCLUSIONS: Malaria in pregnancy was associated with worse cognitive, behavioral, and executive function scores in affected children, but more effective malaria chemoprevention measures did not result in better outcomes. Malaria chemoprevention prior to and early in gestation and with even higher efficacy in mothers and children may be required to prevent neurodevelopmental impairment in children. Clinical Trials Registration. NCT02557425.


Assuntos
Antimaláricos , Artemisininas , Malária , Quinolinas , Criança , Feminino , Gravidez , Humanos , Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Artemisininas/uso terapêutico , Combinação de Medicamentos , Quinolinas/uso terapêutico , Quimioprevenção/métodos
20.
Cochrane Database Syst Rev ; 2(2022)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36321557

RESUMO

BACKGROUND: Description of the condition Malaria, an infectious disease transmitted by the bite of female mosquitoes from several Anopheles species, occurs in 87 countries with ongoing transmission (WHO 2020). The World Health Organization (WHO) estimated that, in 2019, approximately 229 million cases of malaria occurred worldwide, with 94% occurring in the WHO's African region (WHO 2020). Of these malaria cases, an estimated 409,000 deaths occurred globally, with 67% occurring in children under five years of age (WHO 2020). Malaria also negatively impacts the health of women during pregnancy, childbirth, and the postnatal period (WHO 2020). Sulfadoxine/pyrimethamine (SP), an antifolate antimalarial, has been widely used across sub-Saharan Africa as the first-line treatment for uncomplicated malaria sTo examine the effects of folic acid supplementation, at various doses, on malaria susceptibility (risk of infection) and severity among people living in areas with various degrees of malaria endemicity. We will examine the interaction between folic acid supplements and antifolate antimalarial drugs. Specifically, we will aim to answer the following. Among uninfected people living in malaria endemic areas, who are taking or not taking antifolate antimalarials for malaria prophylaxis, does taking a folic acid-containing supplement increase susceptibility to or severity of malaria infection? Among people with malaria infection who are being treated with antifolate antimalarials, does folic acid supplementation increase the risk of treatment failure?Criteria for considering studies for this review Types of studies Inclusion criteria Randomized controlled trials (RCTs) Quasi-RCTs with randomization at the individual or cluster level conducted in malaria-endemic areas (areas with ongoing, local malaria transmission, including areas approaching elimination, as listed in the World Malaria Report 2020) (WHO 2020) Exclusion criteria Ecological studies Observational studies In vivo/in vitro studies Economic studies Systematic literature reviews and meta-analyses (relevant systematic literature reviews and meta-analyses will be excluded but flagged for grey literature screening) Types of participants Inclusion criteria Individuals of any age or gender, living in a malaria endemic area, who are taking antifolate antimalarial medications (inclu


Assuntos
Anemia , Antimaláricos , Antagonistas do Ácido Fólico , Defeitos do Tubo Neural , Criança , Lactente , Gravidez , Recém-Nascido , Feminino , Humanos , Pré-Escolar , Antimaláricos/uso terapêutico , Sulfadoxina/uso terapêutico , Pirimetamina/uso terapêutico , Antagonistas do Ácido Fólico/uso terapêutico , Peso ao Nascer , Parasitemia/tratamento farmacológico , Vitaminas , Ácido Fólico/uso terapêutico , Anemia/tratamento farmacológico , Suplementos Nutricionais , Ferro/uso terapêutico , Recidiva
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