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Asua V, Conrad MD, Aydemir O, Duvalsaint M, Legac J, Duarte E, Tumwebaze P, Chin DM, Cooper RA, Yeka A, Kamya MR, Dorsey G, Nsobya SL, Bailey J, Rosenthal PJ. Changing Prevalence of Potential Mediators of Aminoquinoline, Antifolate, and Artemisinin Resistance Across Uganda. J Infect Dis 2021; 223:985-994. [PMID: 33146722 PMCID: PMC8006419 DOI: 10.1093/infdis/jiaa687] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/27/2020] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND In Uganda, artemether-lumefantrine is recommended for malaria treatment and sulfadoxine-pyrimethamine for chemoprevention during pregnancy, but drug resistance may limit efficacies. METHODS Genetic polymorphisms associated with sensitivities to key drugs were characterized in samples collected from 16 sites across Uganda in 2018 and 2019 by ligase detection reaction fluorescent microsphere, molecular inversion probe, dideoxy sequencing, and quantitative polymerase chain reaction assays. RESULTS Considering transporter polymorphisms associated with resistance to aminoquinolines, the prevalence of Plasmodium falciparum chloroquine resistance transporter (PfCRT) 76T decreased, but varied markedly between sites (0-46% in 2018; 0-23% in 2019); additional PfCRT polymorphisms and plasmepsin-2/3 amplifications associated elsewhere with resistance to piperaquine were not seen. For P. falciparum multidrug resistance protein 1, in 2019 the 86Y mutation was absent at all sites, the 1246Y mutation had prevalence ≤20% at 14 of 16 sites, and gene amplification was not seen. Considering mutations associated with high-level sulfadoxine-pyrimethamine resistance, prevalences of P. falciparum dihydrofolate reductase 164L (up to 80%) and dihydropteroate synthase 581G (up to 67%) were high at multiple sites. Considering P. falciparum kelch protein propeller domain mutations associated with artemisinin delayed clearance, prevalence of the 469Y and 675V mutations has increased at multiple sites in northern Uganda (up to 23% and 41%, respectively). CONCLUSIONS We demonstrate concerning spread of mutations that may limit efficacies of key antimalarial drugs.
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Affiliation(s)
- Victor Asua
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Melissa D Conrad
- University of California, San Francisco, San Francisco, California, USA
| | | | - Marvin Duvalsaint
- University of California, San Francisco, San Francisco, California, USA
| | - Jennifer Legac
- University of California, San Francisco, San Francisco, California, USA
| | - Elias Duarte
- University of California, San Francisco, San Francisco, California, USA
| | | | | | - Roland A Cooper
- Dominican University of California, San Rafael, California, USA
| | - Adoke Yeka
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Moses R Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Grant Dorsey
- University of California, San Francisco, San Francisco, California, USA
| | - Sam L Nsobya
- Infectious Diseases Research Collaboration, Kampala, Uganda
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2
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Old and Recent Advances in Life Cycle, Pathogenesis, Diagnosis, Prevention, and Treatment of Malaria Including Perspectives in Ethiopia. ScientificWorldJournal 2020. [DOI: 10.1155/2020/1295381] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Malaria, caused by apicomplexan parasite, is an old disease and continues to be a major public health threat in many countries. This article aims to present different aspects of malaria including causes, pathogenesis, prevention, and treatment in an articulate and comprehensive manner. Six Plasmodium species are recognized as the etiology of human malaria, of which Plasmodium falciparum is popular in East and Southern Africa. Malaria is transmitted mainly through Anopheles gambiae and Anopheles funestus, the two most effective malaria vectors in the world. Half of the world’s population is at risk for malaria infection. Globally, the morbidity and mortality rates of malaria have become decreased even though few reports in Ethiopia showed high prevalence of malaria. The malaria parasite has a complex life cycle that takes place both inside the mosquito and human beings. Generally, diagnosis of malaria is classified into clinical and parasitological diagnoses. Lack of clear understanding on the overall biology of Plasmodium has created a challenge in an effort to develop new drugs, vaccines, and preventive methods against malaria. However, three types of vaccines and a lot of novel compounds are under perclinical and clinical studies that are triggered by the occurrence of resistance among commonly used drugs and insecticides. Antiadhesion adjunctive therapies are also under investigation in the laboratory. In addition to previously known targets for diagnostic tool, vaccine and drug discovery scientists from all corner of the world are in search of new targets and chemical entities.
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3
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Perumal S, Lee W, Mahmud R, Ismail S, Basir R. In vivo antimalarial potential of tinospora crispa miers in mice and identification of the bioactive compound. Pharmacogn Mag 2020. [DOI: 10.4103/pm.pm_10_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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4
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González R, Pons‐Duran C, Piqueras M, Aponte JJ, ter Kuile FO, Menéndez C. Mefloquine for preventing malaria in pregnant women. Cochrane Database Syst Rev 2018; 11:CD011444. [PMID: 30480761 PMCID: PMC6517148 DOI: 10.1002/14651858.cd011444.pub3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for malaria for all women who live in moderate to high malaria transmission areas in Africa. However, parasite resistance to sulfadoxine-pyrimethamine has been increasing steadily in some areas of the region. Moreover, HIV-infected women on cotrimoxazole prophylaxis cannot receive sulfadoxine-pyrimethamine because of potential drug interactions. Thus, there is an urgent need to identify alternative drugs for prevention of malaria in pregnancy. One such candidate is mefloquine. OBJECTIVES To assess the effects of mefloquine for preventing malaria in pregnant women, specifically, to evaluate:• the efficacy, safety, and tolerability of mefloquine for preventing malaria in pregnant women; and• the impact of HIV status, gravidity, and use of insecticide-treated nets on the effects of mefloquine. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS), the Malaria in Pregnancy Library, and two trial registers up to 31 January 2018. In addition, we checked references and contacted study authors to identify additional studies, unpublished data, confidential reports, and raw data from published trials. SELECTION CRITERIA Randomized and quasi-randomized controlled trials comparing mefloquine IPT or mefloquine prophylaxis against placebo, no treatment, or an alternative drug regimen. DATA COLLECTION AND ANALYSIS Two review authors independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when required. Dichotomous outcomes were compared using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes using mean differences (MDs). We have presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach for the following main outcomes of analysis: maternal peripheral parasitaemia at delivery, clinical malaria episodes during pregnancy, placental malaria, maternal anaemia at delivery, low birth weight, spontaneous abortions and stillbirths, dizziness, and vomiting. MAIN RESULTS Six trials conducted between 1987 and 2013 from Thailand (1), Benin (3), Gabon (1), Tanzania (1), Mozambique (2), and Kenya (1) that included 8192 pregnant women met our inclusion criteria.Two trials (with 6350 HIV-uninfected pregnant women) compared two IPTp doses of mefloquine with two IPTp doses of sulfadoxine-pyrimethamine. Two other trials involving 1363 HIV-infected women compared three IPTp doses of mefloquine plus cotrimoxazole with cotrimoxazole. One trial in 140 HIV-infected women compared three doses of IPTp-mefloquine with cotrimoxazole. Finally, one trial enrolling 339 of unknown HIV status compared mefloquine prophylaxis with placebo.Study participants included women of all gravidities and of all ages (four trials) or > 18 years (two trials). Gestational age at recruitment was > 20 weeks (one trial), between 16 and 28 weeks (three trials), or ≤ 28 weeks (two trials). Two of the six trials blinded participants and personnel, and only one had low risk of detection bias for safety outcomes.When compared with sulfadoxine-pyrimethamine, IPTp-mefloquine results in a 35% reduction in maternal peripheral parasitaemia at delivery (RR 0.65, 95% CI 0.48 to 0.86; 5455 participants, 2 studies; high-certainty evidence) but may have little or no effect on placental malaria infections (RR 1.04, 95% CI 0.58 to 1.86; 4668 participants, 2 studies; low-certainty evidence). Mefloquine results in little or no difference in the incidence of clinical malaria episodes during pregnancy (incidence rate ratio (IRR) 0.83, 95% CI 0.65 to 1.05, 2 studies; high-certainty evidence). Mefloquine decreased maternal anaemia at delivery (RR 0.84, 95% CI 0.76 to 0.94; 5469 participants, 2 studies; moderate-certainty evidence). Data show little or no difference in the proportions of low birth weight infants (RR 0.95, 95% CI 0.78 to 1.17; 5641 participants, 2 studies; high-certainty evidence) and in stillbirth and spontaneous abortion rates (RR 1.20, 95% CI 0.91 to 1.58; 6219 participants, 2 studies; I2 statistic = 0%; moderate-certainty evidence). IPTp-mefloquine increased drug-related vomiting (RR 4.76, 95% CI 4.13 to 5.49; 6272 participants, 2 studies; high-certainty evidence) and dizziness (RR 4.21, 95% CI 3.36 to 5.27; participants = 6272, 2 studies; moderate-certainty evidence).When compared with cotrimoxazole, IPTp-mefloquine plus cotrimoxazole probably results in a 48% reduction in maternal peripheral parasitaemia at delivery (RR 0.52, 95% CI 0.30 to 0.93; 989 participants, 2 studies; moderate-certainty evidence) and a 72% reduction in placental malaria (RR 0.28, 95% CI 0.14 to 0.57; 977 participants, 2 studies; moderate-certainty evidence) but has little or no effect on the incidence of clinical malaria episodes during pregnancy (IRR 0.76, 95% CI 0.33 to 1.76, 1 study; high-certainty evidence) and probably no effect on maternal anaemia at delivery (RR 0.94, 95% CI 0.73 to 1.20; 1197 participants, 2 studies; moderate-certainty evidence), low birth weight rates (RR 1.20, 95% CI 0.89 to 1.60; 1220 participants, 2 studies; moderate-certainty evidence), and rates of spontaneous abortion and stillbirth (RR 1.12, 95% CI 0.42 to 2.98; 1347 participants, 2 studies; very low-certainty evidence). Mefloquine was associated with higher risks of drug-related vomiting (RR 7.95, 95% CI 4.79 to 13.18; 1055 participants, one study; high-certainty evidence) and dizziness (RR 3.94, 95% CI 2.85 to 5.46; 1055 participants, 1 study; high-certainty evidence). AUTHORS' CONCLUSIONS Mefloquine was more efficacious than sulfadoxine-pyrimethamine in HIV-uninfected women or daily cotrimoxazole prophylaxis in HIV-infected pregnant women for prevention of malaria infection and was associated with lower risk of maternal anaemia, no adverse effects on pregnancy outcomes (such as stillbirths and abortions), and no effects on low birth weight and prematurity. However, the high proportion of mefloquine-related adverse events constitutes an important barrier to its effectiveness for malaria preventive treatment in pregnant women.
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Affiliation(s)
- Raquel González
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Clara Pons‐Duran
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Mireia Piqueras
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - John J Aponte
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Feiko O ter Kuile
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolMerseysideUKL3 5QA
| | - Clara Menéndez
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
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Martínez Pérez G, Tarr-Attia CK, Breeze-Barry B, Sarukhan A, Lansana DP, Meyer García-Sípido A, Rosés A, Maixenchs M, Bassat Q, Mayor A. 'Researchers have love for life': opportunities and barriers to engage pregnant women in malaria research in post-Ebola Liberia. Malar J 2018; 17:132. [PMID: 29606141 PMCID: PMC5880008 DOI: 10.1186/s12936-018-2292-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 03/24/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Adoption of prevention and therapeutic innovations to ensure that National Malaria Control Programmes meet their incidence reduction targets is highly dependent on the conduct of rigorous clinical trials. In Liberia, malaria control virtually halted during the recent Ebola epidemic, and could enormously benefit from innovations to protect its most vulnerable populations, including pregnant women, against malaria. Health policy-planners could feel more inclined to adopt novel interventions with demonstrated safety and efficacy when trialled among their women population. However, pregnant women are especially vulnerable when targeted as research participants. Whilst some studies in the region attempted to understand the ethical issues around the conduct of clinical research, there is need of such information from Liberia to inform future malaria research. METHODS This is a grounded theory study that aims to understand the barriers and opportunities for pregnant women to consent to participate in malaria research in Liberia. The study was conducted between November 2016 and May 2017 at the St Joseph's Catholic Hospital, Monrovia. In-depth interviews and focus group discussions were held with hospital staff, traditional community representatives, and pregnant women. RESULTS According to the participants, useful strategies to motivate pregnant women to consent to participate in malaria research could be providing evidence-based education on malaria and research to the general population and encouraging engagement of traditional leaders in research design and community mobilization. Fears and suspicions towards research and researchers, which were amplified during the conduct of Ebola vaccine and drug clinical trials, may influence women's acceptance and willingness to engage in malaria research. Population's mistrust in the public healthcare system might hinder their acceptance of research, undermining the probability of their benefiting from any improved malaria control intervention. CONCLUSION Benchmarking for acceptable practices from previous public health interventions; building community discussion and dissemination platforms; and mapping communication and information errors from how previous research interventions were explained to the Liberian population, are strategies that might help ensure a safe and fully informed participation of pregnant women in malaria research. Inequity issues impeding access and use of biomedical care for women must be tackled urgently.
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Affiliation(s)
- Guillermo Martínez Pérez
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain. .,Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia.
| | - Christine K Tarr-Attia
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Bondey Breeze-Barry
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | - Adelaida Sarukhan
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Dawoh Peter Lansana
- Saint Joseph's Catholic Hospital, Tubman Boulevard, Oldest Congo Town, PO Box 10-512, 1100, Monrovia, Liberia
| | | | - Anna Rosés
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - María Maixenchs
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Quique Bassat
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.,Pediatric Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu, Barcelona, Spain
| | - Alfredo Mayor
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
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6
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González R, Pons‐Duran C, Piqueras M, Aponte JJ, ter Kuile FO, Menéndez C. Mefloquine for preventing malaria in pregnant women. Cochrane Database Syst Rev 2018; 3:CD011444. [PMID: 29561063 PMCID: PMC5875065 DOI: 10.1002/14651858.cd011444.pub2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for malaria for all women who live in moderate to high malaria transmission areas in Africa. However, parasite resistance to sulfadoxine-pyrimethamine has been increasing steadily in some areas of the region. Moreover, HIV-infected women on cotrimoxazole prophylaxis cannot receive sulfadoxine-pyrimethamine because of potential drug interactions. Thus, there is an urgent need to identify alternative drugs for prevention of malaria in pregnancy. One such candidate is mefloquine. OBJECTIVES To assess the effects of mefloquine for preventing malaria in pregnant women, specifically, to evaluate:• the efficacy, safety, and tolerability of mefloquine for preventing malaria in pregnant women; and• the impact of HIV status, gravidity, and use of insecticide-treated nets on the effects of mefloquine. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS), the Malaria in Pregnancy Library, and two trial registers up to 31 January 2018. In addition, we checked references and contacted study authors to identify additional studies, unpublished data, confidential reports, and raw data from published trials. SELECTION CRITERIA Randomized and quasi-randomized controlled trials comparing mefloquine IPT or mefloquine prophylaxis against placebo, no treatment, or an alternative drug regimen. DATA COLLECTION AND ANALYSIS Two review authors independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when required. Dichotomous outcomes were compared using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes using mean differences (MDs). We have presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach for the following main outcomes of analysis: maternal peripheral parasitaemia at delivery, clinical malaria episodes during pregnancy, placental malaria, maternal anaemia at delivery, low birth weight, spontaneous abortions and stillbirths, dizziness, and vomiting. MAIN RESULTS Six trials conducted between 1987 and 2013 from Thailand (1), Benin (3), Gabon (1), Tanzania (1), Mozambique (2), and Kenya (1) that included 8192 pregnant women met our inclusion criteria.Two trials (with 6350 HIV-uninfected pregnant women) compared two IPTp doses of mefloquine with two IPTp doses of sulfadoxine-pyrimethamine. Two other trials involving 1363 HIV-infected women compared three IPTp doses of mefloquine plus cotrimoxazole with cotrimoxazole. One trial in 140 HIV-infected women compared three doses of IPTp-mefloquine with cotrimoxazole. Finally, one trial enrolling 339 of unknown HIV status compared mefloquine prophylaxis with placebo.Study participants included women of all gravidities and of all ages (four trials) or > 18 years (two trials). Gestational age at recruitment was > 20 weeks (one trial), between 16 and 28 weeks (three trials), or ≤ 28 weeks (two trials). Two of the six trials blinded participants and personnel, and only one had low risk of detection bias for safety outcomes.When compared with sulfadoxine-pyrimethamine, IPTp-mefloquine results in a 35% reduction in maternal peripheral parasitaemia at delivery (RR 0.65, 95% CI 0.48 to 0.86; 5455 participants, 2 studies; high-certainty evidence) but may have little or no effect on placental malaria infections (RR 1.04, 95% CI 0.58 to 1.86; 4668 participants, 2 studies; low-certainty evidence). Mefloquine results in little or no difference in the incidence of clinical malaria episodes during pregnancy (incidence rate ratio (IRR) 0.83, 95% CI 0.65 to 1.05, 2 studies; high-certainty evidence). Mefloquine decreased maternal anaemia at delivery (RR 0.84, 95% CI 0.76 to 0.94; 5469 participants, 2 studies; moderate-certainty evidence). Data show little or no difference in the proportions of low birth weight infants (RR 0.95, 95% CI 0.78 to 1.17; 5641 participants, 2 studies; high-certainty evidence) and in stillbirth and spontaneous abortion rates (RR 1.20, 95% CI 0.91 to 1.58; 6219 participants, 2 studies; I2 statistic = 0%; high-certainty evidence). IPTp-mefloquine increased drug-related vomiting (RR 4.76, 95% CI 4.13 to 5.49; 6272 participants, 2 studies; high-certainty evidence) and dizziness (RR 4.21, 95% CI 3.36 to 5.27; participants = 6272, 2 studies; high-certainty evidence).When compared with cotrimoxazole, IPTp-mefloquine plus cotrimoxazole probably results in a 48% reduction in maternal peripheral parasitaemia at delivery (RR 0.52, 95% CI 0.30 to 0.93; 989 participants, 2 studies; moderate-certainty evidence) and a 72% reduction in placental malaria (RR 0.28, 95% CI 0.14 to 0.57; 977 participants, 2 studies; high-certainty evidence) but has little or no effect on the incidence of clinical malaria episodes during pregnancy (IRR 0.76, 95% CI 0.33 to 1.76, 1 study; high-certainty evidence) and probably no effect on maternal anaemia at delivery (RR 0.94, 95% CI 0.73 to 1.20; 1197 participants, 2 studies; moderate-certainty evidence), low birth weight rates (RR 1.20, 95% CI 0.89 to 1.60; 1220 participants, 2 studies; moderate-certainty evidence), and rates of spontaneous abortion and stillbirth (RR 1.12, 95% CI 0.42 to 2.98; 1347 participants, 2 studies; very low-certainty evidence). Mefloquine was associated with higher risks of drug-related vomiting (RR 7.95, 95% CI 4.79 to 13.18; 1055 participants, one study; high-certainty evidence) and dizziness (RR 3.94, 95% CI 2.85 to 5.46; 1055 participants, 1 study; high-certainty evidence). AUTHORS' CONCLUSIONS Mefloquine was more efficacious than sulfadoxine-pyrimethamine in HIV-uninfected women or daily cotrimoxazole prophylaxis in HIV-infected pregnant women for prevention of malaria infection and was associated with lower risk of maternal anaemia, no adverse effects on pregnancy outcomes (such as stillbirths and abortions), and no effects on low birth weight and prematurity. However, the high proportion of mefloquine-related adverse events constitutes an important barrier to its effectiveness for malaria preventive treatment in pregnant women.
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Key Words
- female
- humans
- pregnancy
- insecticide‐treated bednets
- abortion, spontaneous
- abortion, spontaneous/chemically induced
- abortion, spontaneous/epidemiology
- africa south of the sahara
- africa south of the sahara/epidemiology
- antimalarials
- antimalarials/adverse effects
- antimalarials/therapeutic use
- dizziness
- dizziness/chemically induced
- dizziness/epidemiology
- drug combinations
- drug therapy, combination
- hiv infections
- hiv infections/complications
- infant, low birth weight
- malaria
- malaria/epidemiology
- malaria/prevention & control
- mefloquine
- mefloquine/adverse effects
- mefloquine/therapeutic use
- parasitemia
- parasitemia/epidemiology
- pregnancy complications, parasitic
- pregnancy complications, parasitic/epidemiology
- pregnancy complications, parasitic/prevention & control
- pyrimethamine
- pyrimethamine/adverse effects
- pyrimethamine/therapeutic use
- randomized controlled trials as topic
- sulfadoxine
- sulfadoxine/adverse effects
- sulfadoxine/therapeutic use
- thailand
- thailand/epidemiology
- trimethoprim, sulfamethoxazole drug combination
- trimethoprim, sulfamethoxazole drug combination/therapeutic use
- vomiting
- vomiting/chemically induced
- vomiting/epidemiology
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Affiliation(s)
- Raquel González
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Clara Pons‐Duran
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Mireia Piqueras
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - John J Aponte
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
| | - Feiko O ter Kuile
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolUKL3 5QA
| | - Clara Menéndez
- Hospital Clínic ‐ Universitat de BarcelonaISGlobalBarcelonaSpain
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Ali AS, Thawer NG, Khatib B, Amier HH, Shija J, Msellem M, Al-Mafazy AW, Garimo IA, Mkali H, Ramsan MM, Kafuko JM, Paxton LA, Reithinger R, Ngondi JM. Artemisinin combination therapy mass drug administration in a setting of low malaria endemicity: programmatic coverage and adherence during an observational study in Zanzibar. Malar J 2017; 16:332. [PMID: 28807035 PMCID: PMC5557321 DOI: 10.1186/s12936-017-1982-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/07/2017] [Indexed: 11/30/2022] Open
Abstract
Background Mass drug administration (MDA) appears to be effective in reducing the risk of malaria parasitaemia. This study reports on programmatic coverage and compliance of MDA using artemisinin-based combination therapy (ACT) in four shehias (smallest administration unit) that had been identified as hotspots through Zanzibar’s malaria case notification surveillance system. Methods Mass drug administration was done in four shehias selected on the basis of: being an established malaria hot spot; having had mass screening and treatment (MSaT) 2–6 weeks previously; and exceeding the epidemic alert threshold of 5 cases within a week even after MSaT. Communities were sensitized and MDA was conducted using a house-to-house approach. All household members, except pregnant women and children aged less than 2 months, were provided with ACT medicine. Two weeks after the MDA campaign, a survey was undertaken to investigate completion of ACT doses. Results A total of 8816 [97.1% of eligible; 95% confidence interval (CI) 96.8–97.5] people received ACT. During post MDA surveys, 2009 people were interviewed: 90.2% reported having completed MDA doses; 1.9% started treatment but did not complete dosage; 4.7% did not take treatment; 2.0% were absent during MDA and 1.2% were ineligible (i.e. infants <2 months and pregnant women). Main reasons for failure to complete treatment were experience of side-effects and forgetting to take subsequent doses. Failure to take treatment was mainly due to fear of side-effects, reluctance due to lack of malaria symptoms and caregivers forgetting to give medication to children. Conclusion Mass drug administration for malaria was well accepted by communities at high risk of malaria in Zanzibar, with high participation and completion rates. Further work to investigate the potential of MDA in accelerating Zanzibar’s efforts towards malaria elimination should be pursued.
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Affiliation(s)
- Abdullah S Ali
- Zanzibar Malaria Elimination Programme, Ministry of Health, Zanzibar, Tanzania
| | | | - Bakar Khatib
- Zanzibar Malaria Elimination Programme, Ministry of Health, Zanzibar, Tanzania
| | - Haji H Amier
- Zanzibar Malaria Elimination Programme, Ministry of Health, Zanzibar, Tanzania
| | - Joseph Shija
- Zanzibar Malaria Elimination Programme, Ministry of Health, Zanzibar, Tanzania
| | - Mwinyi Msellem
- Zanzibar Malaria Elimination Programme, Ministry of Health, Zanzibar, Tanzania
| | | | | | | | | | - Jessica M Kafuko
- President's Malaria Initiative/United States Agency for International Development, Abuja, Nigeria
| | - Lynn A Paxton
- President's Malaria Initiative/Centers for Disease Control and Prevention, Dar es Salaam, Tanzania
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Almond D, Madanitsa M, Mwapasa V, Kalilani-Phiri L, Webster J, Ter Kuile F, Paintain L. Provider and user acceptability of intermittent screening and treatment for the control of malaria in pregnancy in Malawi. Malar J 2016; 15:574. [PMID: 27894353 PMCID: PMC5126811 DOI: 10.1186/s12936-016-1627-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 11/18/2016] [Indexed: 11/27/2022] Open
Abstract
Background Malaria in pregnancy is a major cause of adverse maternal and fetal outcomes. Intermittent preventive treatment with sulfadoxine–pyrimethamine (IPTp-SP) is one of the control strategies promoted by WHO. In response to mounting resistance to SP, intermittent screening and treatment (ISTp) has been proposed as an alternative. The objective of this study was to explore the acceptability of ISTp for health workers and pregnant women. Methods Semi-structured interviews of ten health workers and five focus group discussions of 38 women enrolled in an ongoing trial comparing IPTp-SP and ISTp with dihydroartemisinin–piperaquine (DP) were conducted at two antenatal clinics in rural Malawi. All transcripts were coded and themes were identified using a content analysis approach. Results Amongst health workers, there were contrasting opinions on the preference of blood sampling methods, and the influence of method on reliability of diagnosis. The perceived greater effectiveness of DP compared to SP was appreciated, however concerns of user compliance with the full dose of DP in non-trial settings were raised. Despite the discomfort of repeated finger pricks, pregnant women were generally accepting of ISTp, particularly the chance for regular blood tests to check for infections and the perceived greater effectiveness with fewer side effects of DP compared to SP. Conclusion In the trial context, pregnant women tended to prefer ISTp-DP over IPTp-SP. Health workers were also accepting of ISTp-DP as an alternative to IPTp-SP in light of increasing SP resistance. However, reliability of stock, adherence to malaria test results and user adherence to the full course of DP may present barriers to successful routine implementation. Effective communication with health workers and between health workers, pregnant women and their communities will be essential for the acceptability of focused antenatal care, including the best malaria control measures available.
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Affiliation(s)
- Deborah Almond
- Disease Control Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Mwayi Madanitsa
- College of Medicine, University of Malawi, Blantyre, Malawi.,Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Victor Mwapasa
- College of Medicine, University of Malawi, Blantyre, Malawi
| | | | - Jayne Webster
- Disease Control Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Feiko Ter Kuile
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Lucy Paintain
- Disease Control Department, London School of Hygiene and Tropical Medicine, London, UK.
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9
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Moore BR, Benjamin JM, Auyeung SO, Salman S, Yadi G, Griffin S, Page-Sharp M, Batty KT, Siba PM, Mueller I, Rogerson SJ, Davis TM. Safety, tolerability and pharmacokinetic properties of coadministered azithromycin and piperaquine in pregnant Papua New Guinean women. Br J Clin Pharmacol 2016; 82:199-212. [PMID: 26889763 PMCID: PMC4917786 DOI: 10.1111/bcp.12910] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/09/2016] [Accepted: 02/14/2016] [Indexed: 12/14/2022] Open
Abstract
AIMS The aim of the present study was to investigate the safety, tolerability and pharmacokinetics of coadministered azithromycin (AZI) and piperaquine (PQ) for treating malaria in pregnant Papua New Guinean women. METHODS Thirty pregnant women (median age 22 years; 16-32 weeks' gestation) were given three daily doses of 1 g AZI plus 960 mg PQ tetraphosphate with detailed monitoring/blood sampling over 42 days. Plasma AZI and PQ were assayed using liquid chromatography-mass spectrometry and high-performance liquid chromatography, respectively. Pharmacokinetic analysis was by population-based compartmental models. RESULTS The treatment was well tolerated. The median (interquartile range) increase in the rate-corrected electrocardiographic QT interval 4 h postdose [12 (6-26) ms(0) (.5) ] was similar to that found in previous studies of AZI given in pregnancy with other partner drugs. Six women with asymptomatic malaria cleared their parasitaemias within 72 h. Two apararasitaemic women developed late uncomplicated Plasmodium falciparum infections on Days 42 and 83. Compared with previous pregnancy studies, the area under the concentration-time curve (AUC0-∞ ) for PQ [38818 (24354-52299) μg h l(-1) ] was similar to published values but there was a 52% increase in relative bioavailability with each dose. The AUC0-∞ for AZI [46799 (43526-49462) μg h l(-1) ] was at least as high as reported for higher-dose regimens, suggesting saturable absorption and/or concentration-dependent tissue uptake and clearance from the central compartment. CONCLUSIONS AZI-PQ appears to be well tolerated and safe in pregnancy. Based on the present/other data, total AZI doses higher than 3 g for the treatment and prevention of malaria may be unnecessary in pregnant women, while clearance of parasitaemia could improve the relative bioavailability of PQ.
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Affiliation(s)
- Brioni R Moore
- School of Medicine and Pharmacology, The University of Western Australia, Crawley, Western Australia, Australia
- Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - John M Benjamin
- Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Siu On Auyeung
- School of Medicine and Pharmacology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Sam Salman
- School of Medicine and Pharmacology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Gumul Yadi
- Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Suzanne Griffin
- Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Madhu Page-Sharp
- School of Pharmacy, Curtin University of Technology, Bentley, Western Australia, Australia
| | - Kevin T Batty
- School of Pharmacy, Curtin University of Technology, Bentley, Western Australia, Australia
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, Madang, Madang Province, Papua New Guinea
| | - Ivo Mueller
- Infection and Immunity, Walter and Eliza Hall Institute, Melbourne, Victoria, Australia
- Barcelona Institute for Global Health (ISGLOBAL), Barcelona, Spain
| | - Stephen J Rogerson
- Department of Medicine (RMH), The University of Melbourne, Parkville, Victoria, Australia
| | - Timothy Me Davis
- School of Medicine and Pharmacology, The University of Western Australia, Crawley, Western Australia, Australia
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Prevalence of Malaria Infection and Risk Factors Associated with Anaemia among Pregnant Women in Semiurban Community of Hazaribag, Jharkhand, India. BIOMED RESEARCH INTERNATIONAL 2015; 2015:740512. [PMID: 26783526 PMCID: PMC4691455 DOI: 10.1155/2015/740512] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 08/13/2015] [Indexed: 01/11/2023]
Abstract
The escalating burden, pathogenesis, and clinical sequel of malaria during pregnancy have combinatorial adverse impact on both mother and foetus that further perplexed the situation of diagnosis, treatment, and prevention. This prompted us to evaluate the status of population at risk of MIP in Hazaribag, Jharkhand, India. Cross-sectional study was conducted over a year at Sadar Hospital, Hazaribag. Malaria was screened using blood smear and/or RDT. Anaemia was defined as haemoglobin concentration. Pretested questionnaires were used to gather sociodemographic, clinical, and obstetrical data. The prevalence of MIP was 5.4% and 4.3% at ANC and DU, and 13.2% malaria was in women without pregnancy. Interestingly, majority were asymptomatically infected with P. vivax (over 85%) at ANC and DU. Peripheral parasitemia was significantly associated with fever within past week, rural origin of subjects, and first/second pregnancies in multivariate analysis, with the highest risk factor associated with fever followed by rural residence. Strikingly in cohort, anaemia was prevalent in 86% at ANC as compared to 72% at DU, whereas severe anaemia was 13.6% and 7.8% at ANC and DU. Even more anaemia prevalence was observed in MIP group (88% and 89% at ANC and DU), whereas severe anaemia was 23% and 21%, respectively. In view of observed impact of anaemia, parasitemia and asymptomatic infection of P. vivax during pregnancy and delivery suggest prompt diagnosis regardless of symptoms and comprehensive drug regime should be offered to pregnant women in association with existing measures in clinical spectrum of MIP, delivery, and its outcome.
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Eugene-Ezebilo DN, Ezebilo EE. Home-based malaria management in children by women: Evidence from a malaria endemic community in sub-Saharan Africa. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2015. [DOI: 10.1016/s2222-1808(15)60831-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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12
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González R, Boerma RS, Sinclair D, Aponte JJ, ter Kuile FO, Menéndez C. Mefloquine for preventing malaria in pregnant women. Hippokratia 2015. [DOI: 10.1002/14651858.cd011444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Raquel González
- Barcelona Institute for Global Health, ISGlobal, Barcelona Ctr. Int. Heath Res. (CRESIB), Hospital Clínic-Universitat de Barcelona; Barcelona Spain
| | - Ragna S Boerma
- Barcelona Institute for Global Health, ISGlobal, Barcelona Ctr. Int. Heath Res. (CRESIB), Hospital Clínic-Universitat de Barcelona; Barcelona Spain
| | - David Sinclair
- Liverpool School of Tropical Medicine; Department of Clinical Sciences; Pembroke Place Liverpool UK L3 5QA
| | - John J Aponte
- Barcelona Institute for Global Health, ISGlobal, Barcelona Ctr. Int. Heath Res. (CRESIB), Hospital Clínic-Universitat de Barcelona; Barcelona Spain
| | - Feiko O ter Kuile
- Liverpool School of Tropical Medicine; Child & Reproductive Health Group; Pembroke Place Liverpool Merseyside UK L3 5QA
| | - Clara Menéndez
- Barcelona Institute for Global Health, ISGlobal, Barcelona Ctr. Int. Heath Res. (CRESIB), Hospital Clínic-Universitat de Barcelona; Barcelona Spain
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The acceptability of intermittent screening and treatment versus intermittent preventive treatment during pregnancy: results from a qualitative study in Northern Ghana. Malar J 2014; 13:432. [PMID: 25404126 PMCID: PMC4240832 DOI: 10.1186/1475-2875-13-432] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 11/03/2014] [Indexed: 11/27/2022] Open
Abstract
Background Affecting mother and child, malaria during pregnancy (MiP) provokes a double morbidity and mortality burden. Within a package of interventions to prevent MiP in endemic areas, the WHO currently recommends intermittent preventive treatment (IPTp). Concerns about anti-malarial resistance have however prompted interest in intermittent screening and treating (IST) as an alternative approach to IPTp. IST involves screening for malaria infection at scheduled antenatal care (ANC) clinic visits and treating malaria cases. In light of the need to comprehensively evaluate new interventions prior to roll out, this article explores the acceptability of IST with artemether-lumefantrine (AL) compared to IPTp with sulphadoxine-pyrimethamine (SP) and in Upper East Region, northern Ghana. Methods Data were collected alongside an open-label, randomized, controlled trial of IST-AL and IPTp-SP in Kassena-Nankana District. Thirty pregnant women enrolled in the clinical trial participated in six focus group discussions. Ten in-depth interviews were carried out with clinical trial staff. Observations were also made at the health facilities where the clinical trial took place. Results Trial participants were generally willing to endure the discomfort of the finger prick necessary for a rapid diagnostic test for malaria and this reflected a wider demand for diagnostic techniques. Reports of side effects were however linked to both trial anti-malarials. Direct complaints about SP were particularly severe with regard to women’s experience of vomiting. Although the follow-up treatment doses of AL for IST were not supervised, based on blister inspection and questioning trial, staff were confident about participants’ adherence to the treatment course. One case of partial adherence to the AL treatment course was reported. Conclusion Despite the discomfort of the finger prick required to perform the intermittent malaria screening, trial participants generally expressed more positive sentiments towards IST-AL than IPTp-SP. Nonetheless, questions remain about adherence to a multiple dose anti-malarial regimen during pregnancy, particularly in endemic areas where MiP is often non-symptomatic. Any implementation of IST must be accompanied by appropriate health messages on adherence and the necessary training for health staff regarding case management.
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Abstract
INTRODUCTION Chemotherapy of malaria has become a rapidly changing field. Less than two decades ago, treatment regimens were increasingly bound to fail due to emerging drug resistance against 4-aminoquinolines and sulfa compounds. By now, artemisinin-based combination therapies (ACTs) constitute the standard of care for uncomplicated falciparum malaria and are increasingly also taken into consideration for the treatment of non-falciparum malaria. AREAS COVERED This narrative review provides an overview of the state-of-art antimalarial drug therapy, highlights the global portfolio of current Phase III/IV clinical trials and summarizes current developments. EXPERT OPINION Malaria chemotherapy remains a dynamic field, with novel drugs and drug combinations continuing to emerge in order to outpace the development of large-scale drug resistance against the currently most important drug class, the artemisinin derivatives. More randomized controlled studies are urgently needed especially for the treatment of malaria in first trimester pregnant women. ACTs should be used for the treatment of imported malaria more consequently. Gaining sufficient efficacy and safety information on ACT use for non-falciparum species including Plasmodium ovale and malariae should be a research priority. Continuous investment into malaria drug development is a vital factor to combat artemisinin resistance and successfully improve malaria control toward the ultimate goal of elimination.
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Affiliation(s)
- Benjamin J Visser
- University of Amsterdam, Academic Medical Centre, Center of Tropical Medicine and Travel Medicine, Division of Infectious Diseases , Amsterdam , The Netherlands
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Moya-Alvarez V, Abellana R, Cot M. Pregnancy-associated malaria and malaria in infants: an old problem with present consequences. Malar J 2014; 13:271. [PMID: 25015559 PMCID: PMC4113781 DOI: 10.1186/1475-2875-13-271] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Accepted: 06/26/2014] [Indexed: 01/10/2023] Open
Abstract
Albeit pregnancy-associated malaria (PAM) poses a potential risk for over 125 million women each year, an accurate review assessing the impact on malaria in infants has yet to be conducted. In addition to an effect on low birth weight (LBW) and prematurity, PAM determines foetal exposure to Plasmodium falciparum in utero and is correlated to congenital malaria and early development of clinical episodes during infancy. This interaction plausibly results from an ongoing immune tolerance process to antigens in utero, however, a complete explanation of this immune process remains a question for further research, as does the precise role of protective maternal antibodies. Preventive interventions against PAM modify foetal exposure to P. falciparum in utero, and have thus an effect on perinatal malaria outcomes. Effective intermittent preventive treatment in pregnancy (IPTp) diminishes placental malaria (PM) and its subsequent malaria-associated morbidity. However, emerging resistance to sulphadoxine-pyrimethamine (SP) is currently hindering the efficacy of IPTp regimes and the efficacy of alternative strategies, such as intermittent screening and treatment (IST), has not been accurately evaluated in different transmission settings. Due to the increased risk of clinical malaria for offspring of malaria infected mothers, PAM preventive interventions should ideally start during the preconceptual period. Innovative research examining the effect of PAM on the neurocognitive development of the infant, as well as examining the potential influence of HLA-G polymorphisms on malaria symptoms, is urged to contribute to a better understanding of PAM and infant health.
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MESH Headings
- Adult
- Africa South of the Sahara/epidemiology
- Antimalarials/administration & dosage
- Antimalarials/therapeutic use
- Comorbidity
- Complement Activation
- Developmental Disabilities/etiology
- Developmental Disabilities/immunology
- Drug Combinations
- Drug Resistance
- Female
- Fetal Diseases/parasitology
- Fetal Diseases/prevention & control
- Fetal Growth Retardation/etiology
- Genetic Predisposition to Disease
- HIV Infections/epidemiology
- HLA-G Antigens/genetics
- HLA-G Antigens/immunology
- Humans
- Immune Tolerance
- Infant, Low Birth Weight
- Infant, Newborn
- Infant, Premature
- Infant, Premature, Diseases/epidemiology
- Infant, Premature, Diseases/parasitology
- Infectious Disease Transmission, Vertical/prevention & control
- Malaria/congenital
- Malaria/drug therapy
- Malaria/embryology
- Malaria/epidemiology
- Malaria/immunology
- Malaria/prevention & control
- Malaria/transmission
- Malaria, Cerebral/complications
- Malaria, Cerebral/embryology
- Malaria, Cerebral/immunology
- Parasitemia/congenital
- Parasitemia/epidemiology
- Parasitemia/transmission
- Plasmodium falciparum/drug effects
- Plasmodium falciparum/genetics
- Pregnancy
- Pregnancy Complications, Infectious/drug therapy
- Pregnancy Complications, Infectious/epidemiology
- Pregnancy Complications, Infectious/immunology
- Pregnancy Complications, Infectious/parasitology
- Pyrimethamine/pharmacology
- Pyrimethamine/therapeutic use
- Risk Factors
- Stillbirth/epidemiology
- Sulfadoxine/pharmacology
- Sulfadoxine/therapeutic use
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Affiliation(s)
- Violeta Moya-Alvarez
- Institut de Recherche pour le Développement, UMR 216 Mère et enfant face aux infections tropicales, Faculté de Pharmacie Paris Descartes, 4 Avenue de l’Observatoire, 75270 Paris, France
- Université Pierre et Marie Curie (Paris 6), Centre Biomédical des Cordeliers, 15, rue de l’Ecole de Médecine, 75006 Paris, France
- Réseau doctoral de l’Ecole des Hautes Etudes en Santé Publique, Avenue du Professeur Léon-Bernard, CS 74312-35043 Rennes, France
| | - Rosa Abellana
- Departament de Salut Pública, Facultat de Medicina, Casanova 143, 08036 Barcelona, Spain
| | - Michel Cot
- Institut de Recherche pour le Développement, UMR 216 Mère et enfant face aux infections tropicales, Faculté de Pharmacie Paris Descartes, 4 Avenue de l’Observatoire, 75270 Paris, France
- Université Pierre et Marie Curie (Paris 6), Centre Biomédical des Cordeliers, 15, rue de l’Ecole de Médecine, 75006 Paris, France
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Biochemical and functional characterization of Plasmodium falciparum GTP cyclohydrolase I. Malar J 2014; 13:150. [PMID: 24745605 PMCID: PMC4005822 DOI: 10.1186/1475-2875-13-150] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 12/17/2013] [Indexed: 12/12/2022] Open
Abstract
Background Antifolates are currently in clinical use for malaria preventive therapy and treatment. The drugs kill the parasites by targeting the enzymes in the de novo folate pathway. The use of antifolates has now been limited by the spread of drug-resistant mutations. GTP cyclohydrolase I (GCH1) is the first and the rate-limiting enzyme in the folate pathway. The amplification of the gch1 gene found in certain Plasmodium falciparum isolates can cause antifolate resistance and influence the course of antifolate resistance evolution. These findings showed the importance of P. falciparum GCH1 in drug resistance intervention. However, little is known about P. falciparum GCH1 in terms of kinetic parameters and functional assays, precluding the opportunity to obtain the key information on its catalytic reaction and to eventually develop this enzyme as a drug target. Methods Plasmodium falciparum GCH1 was cloned and expressed in bacteria. Enzymatic activity was determined by the measurement of fluorescent converted neopterin with assay validation by using mutant and GTP analogue. The genetic complementation study was performed in ∆folE bacteria to functionally identify the residues and domains of P. falciparum GCH1 required for its enzymatic activity. Plasmodial GCH1 sequences were aligned and structurally modeled to reveal conserved catalytic residues. Results Kinetic parameters and optimal conditions for enzymatic reactions were determined by the fluorescence-based assay. The inhibitor test against P. falciparum GCH1 is now possible as indicated by the inhibitory effect by 8-oxo-GTP. Genetic complementation was proven to be a convenient method to study the function of P. falciparum GCH1. A series of domain truncations revealed that the conserved core domain of GCH1 is responsible for its enzymatic activity. Homology modelling fits P. falciparum GCH1 into the classic Tunnelling-fold structure with well-conserved catalytic residues at the active site. Conclusions Functional assays for P. falciparum GCH1 based on enzymatic activity and genetic complementation were successfully developed. The assays in combination with a homology model characterized the enzymatic activity of P. falciparum GCH1 and the importance of its key amino acid residues. The potential to use the assay for inhibitor screening was validated by 8-oxo-GTP, a known GTP analogue inhibitor.
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Yasuoka J, Jimba M, Levins R. Application of loop analysis for evaluation of malaria control interventions. Malar J 2014; 13:140. [PMID: 24713031 PMCID: PMC4017832 DOI: 10.1186/1475-2875-13-140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 04/01/2014] [Indexed: 11/10/2022] Open
Abstract
Background Despite continuous efforts and recent rapid expansion in the financing and implementation of malaria control interventions, malaria still remains one of the most devastating global health issues. Even in countries that have been successful in reducing the incidence of malaria, malaria control is becoming more challenging because of the changing epidemiology of malaria and waning community participation in control interventions. In order to improve the effectiveness of interventions and to promote community understanding of the necessity of continued control efforts, there is an urgent need to develop new methodologies that examine the mechanisms by which community-based malaria interventions could reduce local malaria incidence. Methods This study demonstrated how the impact of community-based malaria control interventions on malaria incidence can be examined in complex systems by qualitative analysis combined with an extensive review of literature. First, sign digraphs were developed through loop analysis to analyse seven interventions: source reduction, insecticide/larvicide use, biological control, treatment with anti-malarials, insecticide-treated mosquito net/long-lasting insecticidal net, non-chemical personal protection measures, and educational intervention. Then, for each intervention, the sign digraphs and literature review were combined to analyse a variety of pathways through which the intervention can influence local malaria incidence as well as interactions between variables involved in the system. Through loop analysis it is possible to see whether increases in one variable qualitatively increases or decreases other variables or leaves them unchanged and the net effect of multiple, interacting variables. Results Qualitative analysis, specifically loop analysis, can be a useful tool to examine the impact of community-based malaria control interventions. Without relying on numerical data, the analysis was able to describe pathways through which each intervention could influence malaria incidence on the basis of the qualitative patterns of the interactions between variables in complex systems. This methodology is generalizable to various disease control interventions at different levels, and can be utilized by a variety of stakeholders such as researchers, community leaders and policy makers to better plan and evaluate their community-based disease control interventions.
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Affiliation(s)
- Junko Yasuoka
- Department of Community and Global Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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Hsiang MS, Hwang J, Tao AR, Liu Y, Bennett A, Shanks GD, Cao J, Kachur SP, Feachem RGA, Gosling RD, Gao Q. Mass drug administration for the control and elimination of Plasmodium vivax malaria: an ecological study from Jiangsu province, China. Malar J 2013; 12:383. [PMID: 24175930 PMCID: PMC3842644 DOI: 10.1186/1475-2875-12-383] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/24/2013] [Indexed: 12/05/2022] Open
Abstract
Background Recent progress in malaria control has caused renewed interest in mass drug administration (MDA) as a potential elimination strategy but the evidence base is limited. China has extensive experience with MDA, but it is not well documented. Methods An ecological study was conducted to describe the use of MDA for the control and elimination of Plasmodium vivax in Jiangsu Province and explore the association between MDA and malaria incidence. Two periods were focused on: 1973 to 1983 when malaria burden was high and MDA administered to highly endemic counties province-wide, and 2000 to 2009, when malaria burden was low and a focal approach was used in two counties. All available data about the strategies implemented, MDA coverage, co-interventions, incidence, and adverse events were collected and described. Joinpoint analysis was used to describe trends in incidence and the relationship between MDA coverage and incidence was explored in negative binomial regression models. Results From 1973 to 1983, MDA with pyrimethamine and primaquine was used on a large scale, with up to 30 million people in target counties covered in a peak year (50% of the total population). Joinpoint analyses identified declines in annual incidence, -56.7% (95% CI -75.5 to -23.7%) from 1973–1976 and -12.4% (95% CI -24.7 to 2.0%) from 1976–1983. Population average negative binomial models identified a relationship between higher total population MDA coverage and lower monthly incidence from 1973–1976, IRR 0.98 (95% CI 0.97 to 1.00), while co-interventions, rainfall and GDP were not associated. From 2000–2009, incidence in two counties declined (annual change -43.7 to -14.0%) during a time when focal MDA using chloroquine and primaquine was targeted to villages and/or individuals residing near passively detected index cases (median 0.04% of total population). Although safety data were not collected systematically, there were rare reports of serious but non-fatal events. Conclusions In Jiangsu Province, China, large-scale MDA was implemented and associated with declines in high P. vivax malaria transmission; a more recent focal approach may have contributed to interruption of transmission. MDA should be considered a potential key strategy for malaria control and elimination.
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Affiliation(s)
- Michelle S Hsiang
- Global Health Group, University of California San Francisco (UCSF), San Francisco, USA.
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Nzila A, Okombo J, Molloy AM. Impact of folate supplementation on the efficacy of sulfadoxine/pyrimethamine in preventing malaria in pregnancy: the potential of 5-methyl-tetrahydrofolate. J Antimicrob Chemother 2013; 69:323-30. [PMID: 24126794 DOI: 10.1093/jac/dkt394] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Malaria remains the leading cause of mortality and morbidity in children under the age of 5 years and pregnant women. To counterbalance the malaria burden in pregnancy, an intermittent preventive treatment strategy has been developed. This is based on the use of the antifolate sulfadoxine/pyrimethamine, taken at specified intervals during pregnancy, and reports show that this approach reduces the malaria burden in pregnancy. Pregnancy is also associated with the risk of neural tube defects (NTDs), especially in women with low folate status, and folic acid supplementation is recommended in pregnancy to lower the risk of NTDs. Thus, in malaria-endemic areas, pregnant women have to take both antifolate medication to prevent malaria and folic acid to lower the risk of NTDs. However, the concomitant use of folate and antifolate is associated with a decrease in antifolate efficacy, exposing pregnant women to malaria. Thus, there is genuine concern that this strategy may not be appropriate. We have reviewed work carried out on malaria folate metabolism and antifolate efficacy in the context of folate supplementation. This review shows that: (i) the folate supplementation effect on antifolate efficacy is dose-dependent, and folic acid doses required to protect pregnant women from NTDs will not decrease antifolate activity; and (ii) 5-methyl-tetrahydrofolate, the predominant form of folate in the blood circulation, could be administered (even at high dose) concomitantly with antifolate without affecting antifolate efficacy. Thus, strategies exist to protect pregnant women from malaria while maintaining adequate folate levels in the body to reduce the occurrence of NTDs.
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Affiliation(s)
- Alexis Nzila
- Department of Biology, King Fahd University of Petroleum and Minerals, PO Box 468, Dhahran, 31261, Saudi Arabia
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Kalilani-Phiri L, Thesing PC, Nyirenda OM, Mawindo P, Madanitsa M, Membe G, Wylie B, Masonbrink A, Makwakwa K, Kamiza S, Muehlenbachs A, Taylor TE, Laufer MK. Timing of malaria infection during pregnancy has characteristic maternal, infant and placental outcomes. PLoS One 2013; 8:e74643. [PMID: 24058614 PMCID: PMC3776740 DOI: 10.1371/journal.pone.0074643] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 08/05/2013] [Indexed: 11/21/2022] Open
Abstract
We conducted a clinical study of pregnant women in Blantyre, Malawi to determine the effect of the timing of malaria infection during pregnancy on maternal, infant and placental outcomes. Women were enrolled in their first or second trimester of their first or second pregnancy and followed every four weeks until delivery. Three doses of sulfadoxine-pyrimethamine were given for intermittent preventive treatment for malaria, and all episodes of parasitemia were treated according to the national guidelines. Placentas were collected at delivery and examined for malaria parasites and pigment by histology. Pregnant women had 0.6 episodes of malaria per person year of follow up. Almost all episodes of malaria were detected at enrollment and malaria infection during the follow up period was rare. Malaria and anemia at the first antenatal visit were independently associated with an increased risk of placental malaria detected at delivery. When all episodes of malaria were treated with effective antimalarial medication, only peripheral malaria infection at the time of delivery was associated with adverse maternal and infant outcomes. One quarter of the analyzed placentas had evidence of malaria infection. Placental histology was 78% sensitive and 89% specific for peripheral malaria infection during pregnancy. This study suggests that in this setting of high antifolate drug resistance, three doses of sulfadoxine-pyrimethamine maintain some efficacy in suppressing microscopically detectable parasitemia, although placental infection remains frequent. Even in this urban setting, a large proportion of women have malaria infection at the time of their first antenatal care visit. Interventions to control malaria early and aggressive case detection are required to limit the detrimental effects of pregnancy-associated malaria.
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Affiliation(s)
- Linda Kalilani-Phiri
- Department of Community Heath, University of Malawi College of Medicine, Blantyre, Malawi
| | - Phillip C. Thesing
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Osward M. Nyirenda
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Patricia Mawindo
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Mwayi Madanitsa
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Gladys Membe
- Department of Obstetrics and Gynaecology, University of Malawi College of Medicine, Blantyre, Malawi
| | - Blair Wylie
- Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Abbey Masonbrink
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Kingsley Makwakwa
- Department of Histopathology, University of Malawi College of Medicine, Blantyre, Malawi
| | - Steve Kamiza
- Department of Histopathology, University of Malawi College of Medicine, Blantyre, Malawi
| | - Atis Muehlenbachs
- Department of Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Terrie E. Taylor
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
- Department of Internal Medicine, College of Osteopathic Medicine, Michigan State University, E. Lansing, Michigan, United States of America
| | - Miriam K. Laufer
- Center for Vaccine Development/HHMI, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
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In vitro and in vivo antimalarial efficacies of optimized tetracyclines. Antimicrob Agents Chemother 2013; 57:3131-6. [PMID: 23629719 DOI: 10.1128/aac.00451-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
With increasing resistance to existing antimalarials, there is an urgent need to discover new drugs at affordable prices for countries in which malaria is endemic. One approach to the development of new antimalarial drugs is to improve upon existing antimalarial agents, such as the tetracyclines. Tetracyclines exhibit potent, albeit relatively slow, action against malaria parasites, and doxycycline is used for both treatment (with other agents) and prevention of malaria. We synthesized 18 novel 7-position modified tetracycline derivatives and screened them for activity against cultured malaria parasites. Compounds with potent in vitro activity and other favorable drug properties were further tested in a rodent malaria model. Ten compounds inhibited the development of cultured Plasmodium falciparum with a 50% inhibitory concentration (IC50) after 96 h of incubation of <30 nM, demonstrating activity markedly superior to that of doxycycline (IC50 at 96 h of 320 nM). Most compounds showed little mammalian cell cytotoxicity and no evidence of in vitro phototoxicity. In a murine Plasmodium berghei model, 13 compounds demonstrated improved activity relative to that of doxycycline. In summary, 7-position modified tetracyclines offer improved activity against malaria parasites compared to doxycycline. Optimized compounds may allow lower doses for treatment and chemoprophylaxis. If safety margins are adequate, dosing in children, the group at greatest risk for malaria in countries in which it is endemic, may be feasible.
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22
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Esposito F. Time-and-space limited chemoprophylaxis: intellectual exercises can be translated into effective public health measures, provided that…. Pathog Glob Health 2012; 106:142-3. [DOI: 10.1179/204777312x13462106637800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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