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1.
PLoS One ; 17(9): e0271011, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112587

RESUMO

Herein, we developed a single and a duplex TaqMan quantitative PCR (qPCR) for absolute quantification of copy numbers of integrated dihydrofolate reductase-thymidylate synthase (mdhfr-ts) drug selectable marker for pyrimethamine resistance in Toxoplasma gondii knockouts (KOs). The single TaqMan qPCR amplifies a 174 bp DNA fragment of the inserted mdhfr-ts and of the wild-type (WT) dhfr-ts (wtdhfr-ts) which is present as single copy gene in Toxoplasma and encodes a sensitive enzyme to pyrimethamine. Thus, the copy number of the dhfr-ts fragment in a given DNA quantity from KO parasites with a single site-specific integration should be twice the number of dhfr-ts copies recorded in the same DNA quantity from WT parasites. The duplex TaqMan qPCR allows simultaneous amplification of the 174 bp dhfr-ts fragment and the T. gondii 529-bp repeat element. Accordingly, for a WT DNA sample, the determined number of tachyzoites given by dhfr-ts amplification is equal to the number of tachyzoites determined by amplification of the Toxoplasma 529-bp, resulting thus in a ratio of 1. However, for a KO clone having a single site-specific integration of mdhfr-ts, the calculated ratio is 2. We then applied both approaches to test T. gondii RH mutants in which the major surface antigen (SAG1) was disrupted through insertion of mdhfr-ts using CRISPR-Cas9. Results from both assays were in correlation showing a high accuracy in detecting KOs with multiple integrated mdhfr-ts. Southern blot analyses using BsaBI and DraIII confirmed qPCRs results. Both TaqMan qPCRs are needed for reliable diagnostic of T. gondii KOs following CRISPR-Cas9-mediated mutagenesis, particularly with respect to off-target effects resulting from multiple insertions of mdhfr-ts. The principle of the duplex TaqMan qPCR is applicable for other selectable markers in Toxoplasma. TaqMan qPCR tools may contribute to more frequent use of WT Toxoplasma strains during functional genomics.


Assuntos
Timidilato Sintase , Toxoplasma , Antígenos de Superfície/farmacologia , Sistemas CRISPR-Cas/genética , DNA/farmacologia , Variações do Número de Cópias de DNA , Mutagênese Sítio-Dirigida , Reação em Cadeia da Polimerase , Pirimetamina/farmacologia , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/metabolismo , Timidilato Sintase/genética , Timidilato Sintase/metabolismo
2.
Toxicology ; 479: 153320, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36108988

RESUMO

Pyrimethamine (PYR) is used to treat parasitic infections including toxoplasmosis, pneumonia and cystoisosporiasis in HIV patients. Various oral medicines have shown phototoxicity therefore, we aimed to study the phototoxicity of PYR and its molecular mechanism involving stress responsive lysosomal protein Lamp2 and mitochondrial mediated signaling pathway under normal UVA/B exposure. We found that photodegradation and subsequent photoproduct formation was evident through LCMS/MS analysis. Photosensitized PYR produces ROS that cause damage to DNA, cell membrane and membrane bound organelles in human keratinocytes. PYR triggered cytotoxicity and phototoxicity that was evident through MTT and NRU assay respectively. Intracellular ROS generation caused phosphatidyl serine (PS) translocation in cell membrane, lysosome membrane permeabilization (LMP) and mitochondrial membrane potential (MMP) collapse that was further validated through caspase3 activation. DNA damage was measured as tail DNA formation and cell cycle arrest in G1 phase. Photosensitized PYR induces oxidative stress in the form of overexpression of Lamp2 that ultimately led to cellular apoptosis. Moreover, the effects of UVB were higher than UVA, probably due to its direct interaction with various macromolecules. We propose that photoexcited PYR may be harmful to human health even at normal sunlight exposure. Therefore, protective procedures should be practiced during PYR medication.


Assuntos
Dermatite Fototóxica , Infecções por HIV , Dermatite Fototóxica/etiologia , Dermatite Fototóxica/metabolismo , Humanos , Queratinócitos , Lisossomos , Fosfatidilserinas/metabolismo , Pirimetamina/metabolismo , Pirimetamina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Luz Solar , Raios Ultravioleta/efeitos adversos
3.
Parasitol Res ; 121(10): 2765-2774, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35980472

RESUMO

A plethora of studies analyse the molecular markers of drug resistance and hence help in guiding the evidence-based malaria treatment policies in India. For reporting mutations, a number of techniques including DNA sequencing, restriction-fragment length polymorphism and mutation-specific polymerase chain reaction have been employed across numerous studies, including variations in the methodology used. However, there is no sufficient data from India comparing these methods as well as report the prevalence of polymorphisms in SP drug resistance molecular markers independently using such methods. Therefore, all data from Indian studies available for molecular marker studies of Plasmodium falciparum drug resistance to sulphadoxine-pyrimethamine was gathered, and a systematic review was performed. This systematic review identifies the molecular methods in use in India and compares each method for detecting sulphadoxine-pyrimethamine drug resistance marker. To delay the spread of drug-resistant parasite strains, a simplified and standardized molecular method is much needed which can be obtained by analysing the performance of each method in use and answering the necessity of newer methodological approaches.


Assuntos
Antimaláricos , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Combinação de Medicamentos , Resistência a Medicamentos/genética , Humanos , Índia/epidemiologia , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico
4.
PLoS Comput Biol ; 18(8): e1010317, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35951528

RESUMO

BACKGROUND: Sulfadoxine-pyrimethamine (SP) is recommended in Africa in several antimalarial preventive regimens including Intermittent Preventive Treatment in pregnant women (IPTp), Intermittent Preventive Treatment in infants (IPTi) and Seasonal Malaria Chemoprevention (SMC). The effectiveness of SP-based preventive treatments are threatened in areas where Plasmodium falciparum resistance to SP is high. The prevalence of mutations in the dihydropteroate synthase gene (pfdhps) can be used to monitor SP effectiveness. IPTi-SP is recommended only in areas where the prevalence of the pfdhps540E mutation is below 50%. It has also been suggested that IPTp-SP does not have a protective effect in areas where the pfdhps581G mutation, exceeds 10%. However, pfdhps mutation prevalence data in Africa are extremely heterogenous and scattered, with data completely missing from many areas. METHODS AND FINDINGS: The WWARN SP Molecular Surveyor database was designed to summarize dihydrofolate reductase (pfdhfr) and pfdhps gene mutation prevalence data. In this paper, pfdhps mutation prevalence data was used to generate continuous spatiotemporal surface maps of the estimated prevalence of the SP resistance markers pfdhps437G, pfdhps540E, and pfdhps581G in Africa from 1990 to 2020 using a geostatistical model, with a Bayesian inference framework to estimate uncertainty. The maps of estimated prevalence show an expansion of the pfdhps437G mutations across the entire continent over the last three decades. The pfdhps540E mutation emerged from limited foci in East Africa to currently exceeding 50% estimated prevalence in most of East and South East Africa. pfdhps540E distribution is expanding at low or moderate prevalence in central Africa and a predicted focus in West Africa. Although the pfdhps581G mutation spread from one focus in East Africa in 2000, to exceeding 10% estimated prevalence in several foci in 2010, the predicted distribution of the marker did not expand in 2020, however our analysis indicated high uncertainty in areas where pfdhps581G is present. Uncertainty was higher in spatial regions where the prevalence of a marker is intermediate or where prevalence is changing over time. CONCLUSIONS: The WWARN SP Molecular Surveyor database and a set of continuous spatiotemporal surface maps were built to provide users with standardized, current information on resistance marker distribution and prevalence estimates. According to the maps, the high prevalence of pfdhps540E mutation was to date restricted to East and South East Africa, which is reassuring for continued use of IPTi and SMC in West Africa, but continuous monitoring is needed as the pfdhps540E distribution is expanding. Several foci where pfdhps581G prevalence exceeded 10% were identified. More data on the pfdhps581G distribution in these areas needs to be collected to guide IPTp-SP recommendations. Prevalence and uncertainty maps can be utilized together to strategically identify sites where increased surveillance can be most informative. This study combines a molecular marker database and predictive modelling to highlight areas of concern, which can be used to support decisions in public health, highlight knowledge gaps in certain regions, and guide future research.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Teorema de Bayes , Combinação de Medicamentos , Resistência a Medicamentos/genética , Feminino , Humanos , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Mutação , Plasmodium falciparum/genética , Gravidez , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , África do Sul , Sulfadoxina , Tetra-Hidrofolato Desidrogenase/genética
5.
Exp Parasitol ; 240: 108344, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35931176

RESUMO

Toxoplasmosis is a disease with a worldwide prevalence that is caused by Toxoplasma gondii. Pyrimethamine and sulfadiazine are two pharmacological agents commonly used to treat of this infection. However, they are accompanied by some side effects. Therefore, the identifying of new drugs with low toxocytosis seems to be a matter of vital importance. Quinolones are DNA replication inhibitors, exerting inhibitory effects against many pathogens, including bacteria, mycoplasma, and protozoa. Given the importance of quinolones and their efficacy, the present in vitro study was conducted to investigate the antiparasitic activities of new quinolones (NFQ-2, NFQ-5, and NFQ-6) containing nitrofuran moiety against T. gondii. To this end, Vero cells were incubated with various concentrations of new quinolones and pyrimethamine (positive control) to determine their viability. Subsequently, they were infected with T. gondii (RH strain) and then subjected to drug treatment. The obtained IC50 values were 3.60, 4.84, 5.59, 3.44 and 2.75 µg/mL for NFQ-2, NFQ-5, NFQ-6, ciprofloxacin and pyrimethamine, respectively. The CC50 values for the NFQ-2, NFQ-5, and NFQ-6 were 25.20, 29.89, and 28.43 µg/mL, indicating the selectivity indexes more than 5 for these compounds. The anti-Toxoplasma efficiency was determined by evaluating infection index, number and size of plaques, and T. gondii intracellular proliferation. As the results indicated, the administration of new quinolone derivatives resulted in the reduction of intracellular proliferation, infection index, and the number and size of plaques in comparison to uninfected treated cells (P < 0.05). The results were indicative of a considerable synergetic effect when each of the derivatives was used in combination with pyrimethamine, compared to when used alone. Based on our results, the nitrofuran-derived quinolones can be considered as new leads for the design of new anti-Toxoplasma agents.


Assuntos
Antiprotozoários , Nitrofuranos , Quinolonas , Toxoplasma , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Chlorocebus aethiops , Nitrofuranos/farmacologia , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Quinolonas/farmacologia , Células Vero
6.
BMC Infect Dis ; 22(1): 668, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927713

RESUMO

BACKGROUND: Uganda accounts for 5% of all malaria cases and deaths reported globally and, in endemic countries, pregnancy is a risk factor for both acquisition of P. falciparum infection and development of severe malaria. In recent years, malaria control has been threatened by COVID-19 pandemic and by the emergence, in Northern Uganda, of both resistance to artemisinin derivatives and to sulfadoxine-pyrimethamine. METHODS: In this facility-based, prospective, observational study, pregnant women will be recruited at antenatal-care visits and followed-up until delivery. Collected data will explore the incidence of asymptomatic parasitemia and malaria-related outcomes, as well as the attitudes towards malaria prevention, administration of intermittent preventive treatment, healthcare seeking behavior and use of insecticide-treated nets. A subpopulation of women diagnosed with malaria will be recruited and their blood samples will be analyzed for detection of genetic markers of resistance to artemisinin derivatives and sulfadoxine-pyrimethamine. Also, to investigate the impact of COVID-19 on malaria care among pregnant women, a retrospective, interrupted-time series will be conducted on at the study sites for the period January 2018 to December 2021. DISCUSSION: The present study will explore the impact of COVID-19 pandemic on incidence of malaria and malaria-related adverse outcomes, along with the prevalence of resistance to artemisinin derivatives and to sulfadoxine-pyrimethamine. To our knowledge, this is the first study aiming to explore the combined effect of these factors on a cohort of pregnant women. TRIAL REGISTRATION: This study has been registered on the ClinicalTrials.gov public website on 26th April, 2022. CLINICALTRIALS: gov Identifier: NCT05348746.


Assuntos
Antimaláricos , Artemisininas , COVID-19 , Malária Falciparum , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Estudos Observacionais como Assunto , Pandemias , Gravidez , Gestantes , Estudos Prospectivos , Pirimetamina/uso terapêutico , Estudos Retrospectivos , Sulfadoxina/uso terapêutico , Uganda/epidemiologia
7.
PLoS One ; 17(8): e0271489, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35939419

RESUMO

Intermittent preventive treatment during pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) is used to prevent malaria and associated unfavorable maternal and foetal outcomes in pregnancy in moderate to high malaria transmission areas. Effectiveness of IPTp-SP is, however, threatened by mutations in the Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes which confer resistance to pyrimethamine and sulfadoxine, respectively. This study determined the prevalence of molecular markers of SP resistance among pregnant women in a high malaria transmission area in the forest-savannah area of Ghana. Genomic DNA was extracted from 286 P. falciparum-positive dried blood spots obtained from pregnant women aged ≥18 years (255 at first Antenatal Care (ANC) clinic visit and 31 at delivery from 2017 to 2019) using Chelex 100. Mutations in Pfdhfr and Pfdhps genes were detected using molecular inversion probes and next generation sequencing. In the Pfdhfr gene, single nucleotide polymorphisms (SNPs) were detected in 83.1% (157/189), 92.0% (173/188) and 91.0% (171/188) at codons 51, 59, and 108 respectively in samples collected at first ANC visit, while SNPs were detected in 96.6 (28/29), 96.6% (28/29) and 96.8% (30/31) in isolates collected at delivery. The Pfdhfr triple mutant N51I, C59R and S108N (IRN) was carried by 80.5% (128/159) and 96.5% (28/29) of the typed isolates collected at ANC visit and at delivery respectively. In the Pfdhps gene, SNPs were detected in 0.6% (1/174), 76.2% (138/181), 33.2% (60/181), 1.2% (2/174), 0% (0/183), and 16.6% (27/173) at codons 431, 436, 437, 540, 581 and 613 respectively in samples collected at ANC, and 0% (0/25), 72% (18/25), 40% (10/25), 3.6% (1/25), 0% (0/29) and 7.4% (2/27) in samples collected at delivery. Quadruple mutant Pfdhfr N51I, C59R, and S108N + Pfdhps A437G (IRN-GK) was present in 25.8% (33/128) and 34.8% (8/23) of isolates at ANC and at delivery respectively. Quintuple mutant alleles Pfdhfr N51I, C59R, and S108N + Pfdhps A437G and K540E (IRN-GE) were detected in 0.8% (1/128) and 4.4% (1/23) of samples collected at ANC and at delivery respectively. No mutations were identified at Pfdhfr codons 16 or 164 or Pfdhps 581. There is a high prevalence of Pfdhfr triple mutant P. falciparum infections among pregnant women in the study area. However, prevalence of the combined Pfdhfr/Pfdhps quadruple and quintuple mutants IRN-GK and IRN-GE respectively prior to commencement of IPTp-SP were low, and no Pfdhps A581G mutant was detected, indicating that SP is still likely to be efficacious for IPTp-SP in the forest-savannah area in the middle belt of Ghana.


Assuntos
Antimaláricos , Malária Falciparum , Adolescente , Adulto , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Combinação de Medicamentos , Resistência a Medicamentos/genética , Feminino , Florestas , Gana/epidemiologia , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum , Polimorfismo de Nucleotídeo Único , Gravidez , Gestantes , Prevalência , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico , Tetra-Hidrofolato Desidrogenase/genética
8.
Malar J ; 21(1): 240, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987638

RESUMO

BACKGROUND: Malaria infection during pregnancy can cause significant morbidity and mortality to a pregnant woman, her fetus and newborn. In areas of high endemic transmission, gravidity is an important risk factor for infection, but there is a complex relationship with other exposure-related factors, and use of protective measures. This study investigated the association between gravidity and placental malaria (PM), among pregnant women aged 14-49 in Kintampo, a high transmission area of Ghana. METHODS: Between 2008 and 2011, as part of a study investigating the association between PM and malaria in infancy, pregnant women attending antenatal care (ANC) clinics in the study area were enrolled and followed up until delivery. The outcome of PM was assessed at delivery by placental histopathology. Multivariable logistic regression analyses were used to investigate the association between gravidity and PM, identify other key risk factors, and control for potential confounders. Pre-specified effect modifiers including area of residence, socio-economic score (SES), ITN use and IPTp-SP use were explored. RESULTS: The prevalence of PM was 65.9% in primigravidae, and 26.5% in multigravidae. After adjusting for age, SES and relationship status, primigravidae were shown to have over three times the odds of PM compared to multigravidae, defined as women with 2 or more previous pregnancies [adjusted OR = 3.36 (95% CI 2.39-4.71), N = 1808, P < 0.001]. The association appeared stronger in rural areas [OR for PG vs. MG was 3.79 (95% CI 3.61-5.51) in rural areas; 2.09 (95% CI 1.17-3.71) in urban areas; P for interaction = 0.07], and among women with lower socio-economic scores [OR for PG vs. MG was 4.73 (95% CI 3.08-7.25) amongst women with lower SES; OR = 2.14 (95% CI 1.38-3.35) among women with higher SES; P for interaction = 0.008]. There was also evidence of lower risk among primigravidae with better use of the current preventive measures IPTp and LLIN. CONCLUSIONS: The burden of PM is most heavily focused on primigravidae of low SES living in rural areas of high transmission. Programmes should prioritize primigravidae and young women of child-bearing age for interventions such as LLIN distribution, educational initiatives and treatment to reduce the burden of malaria in first pregnancy.


Assuntos
Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Antimaláricos/uso terapêutico , Feminino , Gana/epidemiologia , Número de Gestações , Humanos , Recém-Nascido , Malária/prevenção & controle , Placenta , Gravidez , Complicações Parasitárias na Gravidez/prevenção & controle , Gestantes , Pirimetamina , Fatores de Risco , Sulfadoxina
9.
PLoS One ; 17(7): e0271211, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35877761

RESUMO

AIM: This study aimed to ascertain the prevalence and risk factors of malaria and anaemia as well as the impact of preventive methods among pregnant women at the Akatsi South District Hospital of Ghana. SUBJECTS AND METHODS: A hospital based cross-sectional study using simple random sampling technique was conducted among 200 pregnant women receiving antenatal care and laboratory services at the Akatsi District Hospital from May 2016 to July 2016. A semi-structured questionnaire was administered to obtain participants' malaria preventive methods in addition to demographic and gestational details. Participants' hemoglobin and malaria status were assessed using one milliliter (1 ml) whole blood collected from each participant following standard procedures. Factors that produced a p-value of ≤0.2 from the univariate model were included in the final model. Association between potential covariates and the outcomes was assessed using multivariate logistic regression. The Clopper-Pearson test statistic was used to determine the 95% confidence intervals of the outcome variables of interest. We also estimated the population attributable fraction (PAF) of anaemia due to malaria by substituting the adjusted relative risk estimates (RRi) (using the adjrr command in STATA) of anaemia due to malaria into the category-specific attributable formula. P-values of <0.05 were considered statistically significant. RESULTS: Prevalence of anaemia in pregnancy (AiP), malaria in pregnancy (MiP) and AiP/MiP comorbidity was 63.5% (95% CI:56.4-70.2), 11.0% (96% CI:7.0-16.2) and 10.5% (95% CI:6.6-15.6) respectively. Prevalence rates of AiP (66.7%) and MiP (18.5%) predominated among pregnant women aged < 20 years. PAF of AiP due to MiP was 34.5% (95% CI:23.8-43.6). High use of IPTp-SP, 64.0% (95% CI:56.9-70.6) and LLIN, 90.0% (95% CI:85.0-93.8) was observed in this study. Only 42.0% (95% CI:35.1-49.2) used repellent. Not being on the IPTp-SP program posed a 11.70 times risk of MiP (95% CI:2.32-58.96; p = 0.003) compared to pregnant women on the IPTp-SP program. Similarly, not sleeping under LLIN posed an 8.07 times risk of MiP (95% CI:1.98-32.2; p = 0.004) compared to pregnant women who slept under LLIN. Meanwhile, being positive for MiP posed a 12.10 times risk (95% CI:1.35-85.06; p = 0.025) of AiP compared to those negative for malaria whereas failure to attend ANC as scheduled posed 6.34 times risk (95% CI:1.81-22.19; p = 0.004) of AiP among the pregnant women studied. CONCLUSION: The prevalence of MiP and AiP among pregnant women in the Akatsi South District remains a great concern. High utilization of IPTp-SP and LLIN was observed with a resultant positive effect on malaria prevalence among pregnant women. Improved access to IPTp-SP and LLIN is hence encouraged to help further diminish the risk of malaria infection amongst pregnant women in the District.


Assuntos
Anemia , Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Anemia/tratamento farmacológico , Anemia/epidemiologia , Anemia/prevenção & controle , Antimaláricos/uso terapêutico , Estudos Transversais , Combinação de Medicamentos , Feminino , Gana/epidemiologia , Humanos , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/prevenção & controle , Gestantes , Prevalência , Pirimetamina , Fatores de Risco , Sulfadoxina
10.
BMC Pregnancy Childbirth ; 22(1): 599, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896992

RESUMO

BACKGROUND: The World Health Organization recommends a minimum of three doses of quality-assured sulfadoxine-pyrimethamine for intermittent preventive treatment of malaria during pregnancy (IPTp), in moderate to high malaria transmission areas in sub-Saharan Africa. Currently, coverage of IPTp lags behind coverage of antenatal care (ANC) visits; in Nigeria, 57% of women attended four or more ANC visits, whereas only 17% received the recommended three or more doses of IPTp. The innovative program aimed to close this gap by providing counseling on the benefits of comprehensive ANC, referral to ANC and community distribution of IPTp (C-IPTp), complementing IPTp at ANC. The study aimed to examine whether CHW referral to ANC improved the likelihood of receiving three or more doses of IPTp. METHODS: The data for this study were extracted from the maternity record books of 1437 pregnant women seen at 25 public health facilities in Ebonyi State, Nigeria. The outcome of interest was defined as the receipt of three or more doses of IPTp (IPTp3) and the independent variable was referral to ANC by a community health worker for any visit. Descriptive statistics were reported and the results from the multi-level regressions are reported as adjusted odds and prevalence ratios with corresponding 95% confidence intervals. RESULTS: Of the 936 women included in the analysis, 24.47% received the recommended three or more IPTp doses and 61.32% were referred by a community health worker (CHW) for at least one ANC visit. There was no difference in the mean number of ANC visits between women who received C-IPTp and those who received IPTp exclusively at a facility (2.40 vs 2.52; p = 0.374). There were no maternal characteristics associated with CHW referral. Women who were referred by a CHW had 60% greater odds (95% CI, 1.08-2.38) of receiving IPTp3 than those who were never referred. CONCLUSION: The results indicate that CHW referrals conducted within a C-IPTp program are associated with higher IPTp uptake but not fewer ANC visits and that CHWs applied the referral process equally. This strengthens the evidence base for C-IPTp scale-up, which could have a large impact in sub-Saharan Africa in mitigating existing health systems issues.


Assuntos
Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Antimaláricos/uso terapêutico , Agentes Comunitários de Saúde , Combinação de Medicamentos , Feminino , Humanos , Malária/tratamento farmacológico , Malária/prevenção & controle , Nigéria , Gravidez , Complicações Parasitárias na Gravidez/prevenção & controle , Cuidado Pré-Natal , Pirimetamina/uso terapêutico , Encaminhamento e Consulta , Estudos Retrospectivos , Sulfadoxina/uso terapêutico
11.
Trends Parasitol ; 38(8): 673-682, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35688778

RESUMO

African children under 5 years of age bear the main burden of global malaria mortality. Seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine (SP) plus amodiaquine (AQ) given monthly during the rainy season is a highly effective malaria intervention for children aged between 3 months and 5 years living in the Sahel region, a region of intense but seasonal malaria transmission. This intervention is now being considered for other regions of Africa where malaria parasites are more drug resistant. Dihydroartemisinin-piperaquine (DP), an artemisinin-based combination therapy (ACT), has proved to be highly effective and well tolerated in intermittent preventive treatment in pregnant women and children. This combination may be a suitable alternative for SMC. Understanding the safety, pharmacokinetic and pharmacodynamic properties of antimalarial combination therapies is crucial in optimising dosing.


Assuntos
Antimaláricos , Malária , Amodiaquina/uso terapêutico , Antimaláricos/uso terapêutico , Quimioprevenção , Criança , Pré-Escolar , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Lactente , Malária/tratamento farmacológico , Malária/prevenção & controle , Gravidez , Pirimetamina/efeitos adversos , Pirimetamina/uso terapêutico , Estações do Ano , Sulfadoxina/efeitos adversos , Sulfadoxina/uso terapêutico
12.
Malar J ; 21(1): 195, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729612

RESUMO

BACKGROUND: Malaria in pregnancy doubles the risk of low birthweight; up to 11% of all neonatal deaths in sub-Saharan Africa are associated with malaria in pregnancy. To prevent these and other adverse health consequences, the World Health Organization recommends administering intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for all pregnant women at each antenatal care (ANC) visit, starting as early as possible in the second trimester. The target is for countries to administer a minimum of three doses (IPTp3+) to at least 85% of pregnant women. METHODS: A cluster randomized, controlled trial was conducted to assess the effect of delivery of IPTp by community health workers on the coverage of IPTp3 + and ANC visits in Malawi. Community delivery of IPTp was implemented within two districts in Malawi over a 21-month period, from November 2018 to July 2020. In control sites, IPTp was delivered at health facilities. Representative samples of women who delivered in the prior 12 months were surveyed at baseline (n = 370, December 2017) and endline (n = 687, August 2020). A difference in differences analysis was conducted to assess the change in coverage of IPTp and ANC over time, accounting for clustering at the health facility level. RESULTS: Overall IPTp coverage increased over the study period. At baseline, women received a mean of 2.3 IPTp doses (range 0-5 doses) across both arms, and at endline, women received a mean of 2.8 doses (range 0-9 doses). Despite overall increases, the change in IPTp3 + coverage was not significantly different between intervention and control groups (6.9%, 95% CI: -5.9%, 19.6%). ANC4 + coverage increased significantly in the intervention group compared with the control group, with a difference-in-differences of 25.3% points (95% CI: 1.3%, 49.3%). CONCLUSIONS: In order to reduce the burden of malaria in pregnancy, new strategies are needed to improve uptake of effective interventions such as IPTp. While community health workers' delivery of IPTp did not increase uptake in this study, they may be effective in other settings or circumstances. Further research can help identify the health systems characteristics that are conducive to community delivery of IPTp and the operational requirements for effective implementation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03376217. Registered December 6, 2017, https://clinicaltrials.gov/ct2/show/NCT03376217 .


Assuntos
Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Antimaláricos/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Recém-Nascido , Malária/tratamento farmacológico , Malária/prevenção & controle , Malaui , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Complicações Parasitárias na Gravidez/prevenção & controle , Cuidado Pré-Natal , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico
13.
Korean J Parasitol ; 60(2): 109-116, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35500892

RESUMO

Drug resistance is an important problem hindering malaria elimination in tropical areas. Point mutations in Plasmodium falciparum dihydrofolate reductase (Pfdhfr) and dihydropteroate synthase (Pfdhps) genes confer resistance to antifolate drug, sulfadoxine-pyrimethamine (SP) while P. falciparum chloroquine-resistant transporter (Pfcrt) genes caused resistance to chloroquine (CQ). Decline in Pfdhfr/Pfdhps and Pfcrt mutations after withdrawal of SP and CQ has been reported. The aim of present study was to investigate the prevalence of Pfdhfr, Pfdhps, and Pfcrt mutation from 2 endemic areas of Thailand. All of 200 blood samples collected from western area (Thai-Myanmar) and southern area (Thai-Malaysian) contained multiple mutations in Pfdhfr and Pfdhps genes. The most prevalent haplotypes for Pfdhfr and Pfdhps were quadruple and double mutations, respectively. The quadruple and triple mutations of Pfdhfr and Pfdhps were common in western samples, whereas low frequency of triple and double mutations was found in southern samples, respectively. The Pfcrt 76T mutation was present in all samples examined. Malaria isolated from 2 different endemic regions of Thailand had high mutation rates in the Pfdhfr, Pfdhps, and Pfcrt genes. These findings highlighted the fixation of mutant alleles causing resistance of SP and CQ in this area. It is necessary to monitor the re-emergence of SP and CQ sensitive parasites in this area.


Assuntos
Antimaláricos , Cloroquina , Resistência a Medicamentos , Malária Falciparum , Plasmodium falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Combinação de Medicamentos , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico , Tailândia
14.
Front Immunol ; 13: 822567, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572567

RESUMO

Toxoplasma gondii infects one-third of the world population. For decades, it has been considered a silent lifelong infection. However, chronically T. gondii-infected persons may present psychiatric and neurocognitive changes as anxiety, depression, and memory loss. In a model of long-term chronic infection, behavioral alterations parallel neuroinflammation and systemic high cytokine levels, and may reflect brain cyst load. Recent findings support that in chronic infection an active parasite-host interplay involves an immune-mediated control of tissue cysts. Here, we tested the idea that etiological treatment in chronic phase may add advantage to intrinsic immune-mediated cyst control and impact behavioral changes. Thus, we combined sulfadiazine-plus-pyrimethamine (S+P), the first-choice therapy for toxoplasmosis, to study the association of brain cyst load and biological processes related to the immune response (neuroinflammation, blood-brain barrier -BBB- disruption and serum cytokine levels), with behavioral and neurocognitive changes of long-term chronic infection. Female C57BL/6 mice (H-2b) were infected (5 cysts, ME-49 strain) and treated with S+P from 30 to 60 days postinfection (dpi), compared with vehicle (Veh)-treated and noninfected controls. At endpoints (pre-therapy, 30 dpi; S+P therapy, 60 dpi; after ceased therapy, 90 dpi), independent groups were subjected to behavioral tests, and brain tissues and sera were collected. Multiple behavioral and neurocognitive changes were detected in the early (30 dpi) and long-term (60 and 90 dpi) chronic infection. S+P therapy resolved locomotor alterations, anxiety, and depressive-like behavior, partially or transiently ameliorated hyperactivity and habituation memory loss. Analysis after therapy cessation showed that S+P therapy reduced the number of stimuli required for aversive memory consolidation. S+P therapy resulted in reduced brain cyst load, neuroinflammation and BBB disruption, and lowered systemic Th1-cytokine levels. Correlation analysis revealed association between IFNγ, TNF and MCP-1/CCL2 serum levels, brain cyst load and behavioral and neurocognitive alterations. Moreover, principal-component analysis (PCA-2D and 3D projections) highlighted distinction between clusters (noninfected; Veh-treated and S+P-treated infected). Thus, our data suggest that S+P therapy added gain to intrinsic brain cyst control and, direct or indirectly, ameliorated inflammation-related alterations, traits associated with behavioral and neurocognitive alterations.


Assuntos
Encéfalo , Pirimetamina , Sulfadiazina , Toxoplasmose , Animais , Encéfalo/parasitologia , Citocinas , Feminino , Inflamação/tratamento farmacológico , Transtornos da Memória/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadiazina/farmacologia , Sulfadiazina/uso terapêutico , Toxoplasmose/tratamento farmacológico , Toxoplasmose/patologia
15.
Ann Glob Health ; 88(1): 27, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35582408

RESUMO

Background: Intermittent preventive treatment of malaria in pregnancy with Sulphadoxine-Pyrimethamine (IPTp-SP) tablets is one of the recommended interventions to reduce the burden of malaria on both the pregnant woman and the unborn child. The aim of this study was to assess the prevalence of IPTp-SP uptake and its associated factors in the Atwima Kwanwoma District of Ashanti Region, Ghana. Methods: The study was cross sectional. A structured questionnaire was administered to 394 respondents, comprising pregnant women in their last two months of pregnancy and nursing mothers who delivered within three months prior to the study. Medical records of the respondents were also reviewed. Descriptive statistics such as simple proportions, and averages were computed. Chi-square test and multiple logistic regression analysis were performed to determine factors associated with IPTp-SP uptake. Results: The average age of the respondents was 28.2 (±5.9) years. Almost all of the respondents (98%) had received SP at the time of the study. Fifty percent received their first dose of SP between 16 and 19 weeks of gestation. The multiple logistic regression analysis showed a statistically significant association between IPTp-SP uptake and educational level, time of first ANC visit, number of ANC visits and receiving education on SP prior to the administration of the drug. Conclusion: Education on SP use should be intensified at all levels of the health system. Early initiation of ANC is also recommended for optimal uptake of IPTp-SP. More research is needed to understand factors affecting the uptake of SP during pregnancy in the country.


Assuntos
Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Adulto , Antimaláricos/uso terapêutico , Estudos Transversais , Combinação de Medicamentos , Feminino , Gana/epidemiologia , Humanos , Malária/tratamento farmacológico , Malária/epidemiologia , Malária/prevenção & controle , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina , Sulfadoxina , Adulto Jovem
16.
Clin Pharmacol Ther ; 112(3): 687-698, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35527512

RESUMO

Endogenous biomarkers for transporter-mediated drug-drug interaction (DDI) predictions represent a promising approach to facilitate and improve conventional DDI investigations in clinical studies. This approach requires high sensitivity and specificity of biomarkers for the targets of interest (e.g., transport proteins), as well as rigorous characterization of their kinetics, which can be accomplished utilizing physiologically-based pharmacokinetic (PBPK) modeling. Therefore, the objective of this study was to develop PBPK models of the endogenous organic cation transporter (OCT)2 and multidrug and toxin extrusion protein (MATE)1 substrates creatinine and N1 -methylnicotinamide (NMN). Additionally, this study aimed to predict kinetic changes of the biomarkers during administration of the OCT2 and MATE1 perpetrator drugs trimethoprim, pyrimethamine, and cimetidine. Whole-body PBPK models of creatinine and NMN were developed utilizing studies investigating creatinine or NMN exogenous administration and endogenous synthesis. The newly developed models accurately describe and predict observed plasma concentration-time profiles and urinary excretion of both biomarkers. Subsequently, models were coupled to the previously built and evaluated perpetrator models of trimethoprim, pyrimethamine, and cimetidine for interaction predictions. Increased creatinine plasma concentrations and decreased urinary excretion during the drug-biomarker interactions with trimethoprim, pyrimethamine, and cimetidine were well-described. An additional inhibition of NMN synthesis by trimethoprim and pyrimethamine was hypothesized, improving NMN plasma and urine interaction predictions. To summarize, whole-body PBPK models of creatinine and NMN were built and evaluated to better assess creatinine and NMN kinetics while uncovering knowledge gaps for future research. The models can support investigations of renal transporter-mediated DDIs during drug development.


Assuntos
Cimetidina , Pirimetamina , Biomarcadores , Cimetidina/farmacocinética , Creatinina , Interações Medicamentosas , Humanos , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Preparações Farmacêuticas , Pirimetamina/farmacologia , Trimetoprima/farmacologia
17.
Malar J ; 21(1): 110, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361195

RESUMO

BACKGROUND: Malaria in Mali remains a primary cause of morbidity and mortality, with women at high risk during pregnancy for placental malaria (PM). Risk for PM and its association with birth outcomes was evaluated in a rural to urban longitudinal cohort on the Bandiagara Escarpment and the District of Bamako. METHODS: Placental samples (N = 317) were collected from 249 mothers who were participants in a prospective cohort study directed by BIS in the years 2011 to 2019. A placental pathologist and research assistant evaluated the samples by histology in blinded fashion to assess PM infection stage and parasite density. Generalized estimating equations (GEE) were used to model the odds of PM infection. RESULTS: In a multivariable model, pregnancies in Bamako, beyond secondary education, births in the rainy season (instead of the hot dry season), and births to women who had ≥ 3 doses of sulfadoxine-pyrimethamine (SP) instead of no doses were associated with reduced odds of experiencing PM (active and past infections combined). Births in later years of the study were strongly associated with reduced odds of PM. Maternal age, which was positively associated with offspring year of birth, was significant as a predictor of PM only if offspring year of birth was omitted from the model. Gravidity was positively associated with both maternal age and offspring year of birth such that if either variable was included in the model, then gravidity was no longer significant. However, if maternal age or year of offspring birth were not adjusted for, then the odds of PM were nearly two-fold higher in primigravida compared to multigravida. Birth outcomes improved (+ 285 g birth weight, + 2 cm birth length, + 75 g placental weight) for women who had ≥ 3 doses of SP compared to no doses, but no difference was detected in birth weight or length for women who had 2 instead of ≥ 3 SP doses. However, at 2 instead of ≥ 3 doses placentas were 36 g lighter and the odds of low birth weight (< 2500 g) were 14% higher. Severe parasite densities (> 10% erythrocytes infected) were significantly associated with decreases in birth weight, birth length, and placental weight, as were chronic PM infections. The women who received no SP during pregnancy (7% of the study total) were younger and lacked primary school education. The women who received ≥ 3 doses of SP came from more affluent families. CONCLUSIONS: Women who received no doses of SP during pregnancy experienced the most disadvantageous birth outcomes in both Bamako and on the Bandiagara Escarpment. Such women tended to be younger and to have had no primary school education. Targeting such women for antenatal care, which is the setting in which SP is most commonly administered in Mali, will have a more positive impact on public health than focusing on the increment from two to three doses of SP, although that increment is also desirable.


Assuntos
Malária , Placenta , Estudos de Coortes , Combinação de Medicamentos , Feminino , Número de Gestações , Humanos , Malária/epidemiologia , Malária/prevenção & controle , Mali/epidemiologia , Placenta/parasitologia , Gravidez , Estudos Prospectivos , Pirimetamina , Fatores de Risco , Sulfadoxina
18.
Malar J ; 21(1): 107, 2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35346205

RESUMO

BACKGROUND: Despite decades of prevention efforts, the burden of malaria in pregnancy (MiP) remains a great public health concern. Sulfadoxine-pyrimethamine (SP), used as intermittent preventive treatment in pregnancy (IPTp-SP) is an important component of the malaria prevention strategy implemented in Africa. However, IPTp-SP is under constant threat from parasite resistance, thus requires regular evaluation to inform decision-making bodies. METHODS: In two malaria endemic communities in the Volta region (Adidome and Battor), a cross-sectional hospital-based study was conducted in pregnant women recruited at their first antenatal care (ANC) visit and at delivery. Basic clinical and demographic information were documented and their antenatal records were reviewed to confirm IPTp-SP adherence. Peripheral and placental blood were assayed for the presence of Plasmodium falciparum parasites by quantitative polymerase chain reaction (qPCR). One hundred and twenty (120) positive samples were genotyped for mutations associated with SP resistance. RESULTS: At first ANC visit, P. falciparum prevalence was 28.8% in Adidome and 18.2% in Battor. At delivery, this decreased to 14.2% and 8.2%, respectively. At delivery, 66.2% of the women had taken at least the recommended 3 or more doses of IPTp-SP and there was no difference between the two communities. Taking at least 3 IPTp-SP doses was associated with an average birth weight increase of more than 360 g at both study sites compared to women who did not take treatment (p = 0.003). The Pfdhfr/Pfdhps quintuple mutant IRNI-A/FGKAA was the most prevalent (46.7%) haplotype found and the nonsynonymous Pfdhps mutation at codon A581G was higher at delivery among post-SP treatment isolates (40.6%) compared to those of first ANC (10.22%). There was also an increase in the A581G mutation in isolates from women who took 3 or more IPTp-SP. CONCLUSIONS: This study confirms a positive impact following the implementation of the new IPTp-SP policy in Ghana in increasing the birth weight of newborns. However, the selection pressure exerted by the recommended 3 or more doses of IPTp-SP results in the emergence of parasites carrying the non-synonymous mutation on codon A581G. This constant selective pressure calls into question the time remaining for the clinical utility of IPTp-SP treatment during pregnancy in Africa.


Assuntos
Antimaláricos , Malária Falciparum , Plasmodium falciparum/efeitos dos fármacos , Complicações Parasitárias na Gravidez , Antimaláricos/uso terapêutico , Estudos Transversais , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Gana/epidemiologia , Humanos , Recém-Nascido , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Placenta , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/prevenção & controle , Cuidado Pré-Natal , Pirimetamina , Sulfadoxina
19.
Antimicrob Agents Chemother ; 66(4): e0194521, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35266823

RESUMO

Molecular surveillance of Plasmodium falciparum parasites is important to track emerging and new mutations and trends in established mutations and should serve as an early warning system for antimalarial resistance. Dried blood spots were obtained from a Plasmodium falciparum malaria survey in school children conducted across eight counties in western Kenya in 2019. Real-time PCR identified 500 P. falciparum-positive samples that were amplified at five drug resistance loci for targeted amplicon deep sequencing (TADS). The absence of important kelch 13 mutations was similar to previous findings in Kenya pre-2019, and low-frequency mutations were observed in codons 569 and 578. The chloroquine resistance transporter gene codons 76 and 145 were wild type, indicating that the parasites were chloroquine and piperaquine sensitive, respectively. The multidrug resistance gene 1 haplotypes based on codons 86, 184, and 199 were predominantly present in mixed infections with haplotypes NYT and NFT, driven by the absence of chloroquine pressure and the use of lumefantrine, respectively. The sulfadoxine-pyrimethamine resistance profile was a "superresistant" combination of triple mutations in both Pfdhfr (51I 59R 108N) and Pfdhps (436H 437G 540E), rendering sulfadoxine-pyrimethamine ineffective. TADS highlighted the low-frequency variants, allowing the early identification of new mutations, Pfmdr1 codon 199S and Pfdhfr codon 85I and emerging 164L mutations. The added value of TADS is its accuracy in identifying mixed-genotype infections and for high-throughput monitoring of antimalarial resistance markers.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Criança , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Códon , Combinação de Medicamentos , Resistência a Medicamentos/genética , Antagonistas do Ácido Fólico/farmacologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Quênia , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/uso terapêutico , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico
20.
Malar J ; 21(1): 104, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35331231

RESUMO

Chemoprevention strategies reduce malaria disease and death, but the efficacy of anti-malarial drugs used for chemoprevention is perennially threatened by drug resistance. This review examines the current impact of chemoprevention on the emergence and spread of drug resistant malaria, and the impact of drug resistance on the efficacy of each of the chemoprevention strategies currently recommended by the World Health Organization, namely, intermittent preventive treatment in pregnancy (IPTp); intermittent preventive treatment in infants (IPTi); seasonal malaria chemoprevention (SMC); and mass drug administration (MDA) for the reduction of disease burden in emergency situations. While the use of drugs to prevent malaria often results in increased prevalence of genetic mutations associated with resistance, malaria chemoprevention interventions do not inevitably lead to meaningful increases in resistance, and even high rates of resistance do not necessarily impair chemoprevention efficacy. At the same time, it can reasonably be anticipated that, over time, as drugs are widely used, resistance will generally increase and efficacy will eventually be lost. Decisions about whether, where and when chemoprevention strategies should be deployed or changed will continue to need to be made on the basis of imperfect evidence, but practical considerations such as prevalence patterns of resistance markers can help guide policy recommendations.


Assuntos
Malária , Sulfadoxina , Quimioprevenção/métodos , Combinação de Medicamentos , Resistência a Medicamentos/genética , Feminino , Humanos , Lactente , Malária/tratamento farmacológico , Malária/prevenção & controle , Políticas , Gravidez , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico
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