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Maciver SK, Abdelnasir S, Anwar A, Siddiqui R, Khan NA. Modular nanotheranostic agents for protistan parasitic diseases: Magic bullets with tracers. Mol Biochem Parasitol 2023; 253:111541. [PMID: 36603708 DOI: 10.1016/j.molbiopara.2022.111541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 12/12/2022] [Accepted: 12/19/2022] [Indexed: 01/04/2023]
Abstract
Protistan parasitic infections contribute significantly to morbidity and mortality, causing more than 2 billion human infections annually. However, current treatments are often limited; due to ineffective drugs and drug resistance, thus better options are urgently required. In the present context, theranostics agents are those that offer simultaneous detection, diagnosis and even treatment of protistan parasitic diseases. "Nanotheranostics" is the term used to describe such agents, that are around 100 nm or less in size. Anti-parasitic activity of nanoparticles (NPs) has been reported, and many have useful intrinsic imaging properties, but it is perhaps their multifunctional nature that offers the greatest potential. NPs may be used as adapters onto which various subunits with different functions may be attached. These subunits may facilitate targeting parasites, coupled with toxins to eradicate parasites, and probe subunits for detection of particles and/or parasites. The modular nature of nano-platforms promises a "mix and match" approach for the construction of tailored agents by using combinations of these subunits against different protistan parasites. Even though many of the subunits have shown promise alone, these have not yet been put together convincingly enough to form working theranostics against protistan parasites. Although the clinical application of nanotheranostics to protistan parasitic infections in humans requires more research, we conclude that they offer not just a realisation of Paul Ehrlich's long imagined "magic bullet" concept, but potentially are magic bullets combined with tracer bullets.
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Affiliation(s)
- Sutherland Kester Maciver
- Centre for Discovery Brain Science, Edinburgh Medical School, Biomedical Sciences, University of Edinburgh, Scotland, UK
| | - Sumayah Abdelnasir
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Subang Jaya 47500, Selangor, Malaysia
| | - Ayaz Anwar
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Subang Jaya 47500, Selangor, Malaysia.
| | - Ruqaiyyah Siddiqui
- College of Arts and Sciences, American University of Sharjah, Sharjah, United Arab Emirates; Department of Medical Biology, Faculty of Medicine, Istinye University, Istanbul 34010, Turkey
| | - Naveed Ahmed Khan
- Department of Medical Biology, Faculty of Medicine, Istinye University, Istanbul 34010, Turkey; Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.
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Bihoun B, Zango SH, Traoré-Coulibaly M, Valea I, Ravinetto R, Van Geertruyden JP, D'Alessandro U, Tinto H, Robert A. Age-modified factors associated with placental malaria in rural Burkina Faso. BMC Pregnancy Childbirth 2022; 22:248. [PMID: 35331181 PMCID: PMC8951713 DOI: 10.1186/s12884-022-04568-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/31/2022] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Malaria in pregnancy can result in placental infection with fetal implications. This study aimed at assessing placental malaria (PM) prevalence and its associated factors in a cohort of pregnant women with peripheral malaria and their offspring. METHOD The data were collected in the framework of a clinical trial on treatments for malaria in pregnant women . Placental malaria (PM) was diagnosed by histopathological detection of parasites and/or malaria pigment on placenta biopsies taken at delivery. Factors associated with PM were assessed using logistic regression. RESULTS Out of 745 biopsies examined, PM was diagnosed in 86.8 % of women. Acute, chronic and past PM were retrieved in 11 (1.5 %), 170 (22.8 %), and 466 (62.6 %) women, respectively. A modifying effect was observed in the association of gravidity or anemia at the study start with pooled PM (presence of parasites and/or malaria pigment). In women under 30, gravidity ≤ 2 was associated with an increased prevalence of pooled PM but in women aged 30 years or more, gravidity was no more associated with pooled PM (OR 6.81, 95 % CI 3.18 - 14.60; and OR 0.52, 95 % CI 0.10 - 2.76, respectively). Anemia was associated with pooled PM in women under 30 (OR 1.96, 95 % CI 1.03 - 3.72) but not in women aged 30 years or more (OR 0.68, 95 % CI 0.31 - 1.49). Similarly, the association of gravidity with past-chronic PM depended also on age. A higher prevalence of active PM was observed in women under 30 presenting with symptomatic malaria (OR 3.79, 95 % CI 1.55 - 9.27), while there was no significant increase in the prevalence of active PM (presence of parasites only) in women with symptomatic malaria when aged 30 years or more (OR 0.42, 95 % CI 0.10 - 1.75). In women with chronic PM, the prevalence of low birth weight or prematurity was the highest (31.2 %) as compared with past PM or no PM. CONCLUSION Despite the rapid diagnosis and efficacious treatment of peripheral infection, the prevalence of placental malaria remained high in women with P. falciparum peripheral infection in Nanoro, especially in younger women This underlines the importance of preventive measures in this specific group.
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Affiliation(s)
- Biébo Bihoun
- Unité de recherche clinique de Nanoro, Institut de recherche en science de la santé, Nanoro, Burkina Faso.
| | - Serge Henri Zango
- Unité de recherche clinique de Nanoro, Institut de recherche en science de la santé, Nanoro, Burkina Faso.,Pôle Epidémiologie et Biostatistiques, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
| | - Maminata Traoré-Coulibaly
- Unité de recherche clinique de Nanoro, Institut de recherche en science de la santé, Nanoro, Burkina Faso
| | - Innocent Valea
- Unité de recherche clinique de Nanoro, Institut de recherche en science de la santé, Nanoro, Burkina Faso
| | | | | | - Umberto D'Alessandro
- MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, Gambia
| | - Halidou Tinto
- Unité de recherche clinique de Nanoro, Institut de recherche en science de la santé, Nanoro, Burkina Faso
| | - Annie Robert
- Pôle Epidémiologie et Biostatistiques, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium
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Osarfo J, Ampofo GD, Tagbor H. Trends of malaria infection in pregnancy in Ghana over the past two decades: a review. Malar J 2022; 21:3. [PMID: 34983534 PMCID: PMC8725495 DOI: 10.1186/s12936-021-04031-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 12/17/2021] [Indexed: 02/07/2023] Open
Abstract
Background There has been a global decline in malaria transmission over the past decade. However, not much is known of the impact of this observation on the burden of malaria infection in pregnancy in endemic regions including Ghana. A narrative review was undertaken to help describe trends in malaria infection in pregnancy in Ghana. Among others, such information is important in showing any progress made in malaria in pregnancy control. Methods To describe trends in pregnancy-associated malaria infection in Ghana, a search and review of literature reporting data on the prevalence of asymptomatic Plasmodium falciparum infection in pregnancy was conducted. Results Thirty-six (36) studies, conducted over 1994–2019, were included in the review. In the northern savannah zone with largely seasonal malaria transmission, prevalence appeared to reduce from about 50–60% in 1994–2010 to 13–26% by 2019. In the middle transitional/forest zone, where transmission is perennial with peaks in the rainy season, prevalence apparently reduced from 60% in the late 1990 s to about 5–20% by 2018. In the coastal savannah area, there was apparent reduction from 28 to 35% in 2003–2010 to 5–11% by 2018–2019. The burden of malaria infection in pregnancy continues to be highest among teenagers and younger-aged pregnant women and paucigravidae. Conclusions There appears to be a decline in asymptomatic parasite prevalence in pregnancy in Ghana though this has not been uniform across the different transmission zones. The greatest declines were noticeably in urban settings. Submicroscopic parasitaemia remains a challenge for control efforts. Further studies are needed to evaluate the impact of the reduced parasite prevalence on maternal anaemia and low birthweight and to assess the local burden of submicroscopic parasitaemia in relation to pregnancy outcomes. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-04031-3.
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Affiliation(s)
- Joseph Osarfo
- Department of Community Medicine, School of Medicine, University of Health and Allied Sciences, Ho, Volta Region, Ghana.
| | - Gifty Dufie Ampofo
- Department of Community Medicine, School of Medicine, University of Health and Allied Sciences, Ho, Volta Region, Ghana
| | - Harry Tagbor
- Department of Community Medicine, School of Medicine, University of Health and Allied Sciences, Ho, Volta Region, Ghana
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Niikura M, Fukutomi T, Mineo S, Mitobe J, Kobayashi F. The association between acute fatty liver disease and nitric oxide during malaria in pregnancy. Malar J 2021; 20:462. [PMID: 34906158 PMCID: PMC8670279 DOI: 10.1186/s12936-021-03999-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/01/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Liver disease is a common feature of malaria in pregnancy, but its pathogenesis remains unclear. METHODS To understand the pathogenesis of liver disease during malaria in pregnancy, comparative proteomic analysis of the liver in a mouse model of malaria in pregnancy was performed. RESULTS Decreased levels of mitochondrial and peroxisomal proteins were observed in the livers of pregnant mice infected with the lethal rodent malaria parasite Plasmodium berghei strain NK65. By contrast, increased levels of perilipin-2, amyloid A-1, and interferon (IFN)-γ signalling pathway-related proteins were observed in the livers of infected pregnant mice, suggesting that IFN-γ signalling may contribute to the development of liver disease during malaria in pregnancy. IFN-γ signalling is a potential trigger of inducible nitric oxide synthase (iNOS) expression. Liver disease associated with microvesicular fatty infiltration and elevated liver enzymes in pregnant wild-type mice infected with malaria parasites was improved by iNOS deficiency. CONCLUSIONS In this study, a causative role of iNOS in liver disease associated with microvesicular fatty infiltration during malaria in pregnancy was demonstrated. These findings provide important insight for understanding the role of iNOS-mediated metabolic responses and the pathogenesis of high-risk liver diseases in pregnancy, such as acute fatty liver.
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Affiliation(s)
- Mamoru Niikura
- Department of Infectious Diseases, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo, 181-8611, Japan.
| | - Toshiyuki Fukutomi
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Tokyo, Japan
| | - Shoichiro Mineo
- Department of Molecular Pathology, Tokyo Medical University, Tokyo, 160-8402, Japan
| | - Jiro Mitobe
- Department of Infectious Diseases, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo, 181-8611, Japan
| | - Fumie Kobayashi
- Department of Environmental Science, School of Life and Environmental Science, Azabu University, Kanagawa, 252-5201, Japan
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Kumar R, Farzeen M, Hafeez A, Achakzai BK, Vankwani M, Lal M, Iqbal R, Somrongthong R. Effectiveness of a health education intervention on the use of long-lasting insecticidal nets for the prevention of malaria in pregnant women of Pakistan: a quasi-experimental study. Malar J 2020; 19:232. [PMID: 32600347 PMCID: PMC7325083 DOI: 10.1186/s12936-020-03298-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 06/17/2020] [Indexed: 11/10/2022] Open
Abstract
Background About one quarter of pregnant women in the population of Pakistan are using long-lasting insecticide-treated bed nets (LLINs) for prevention of malaria. Past research reported that adequate information and education would act as mediator to change behaviour among patients for prevention of malaria infection. The effective use of LLINs would contribute to reduction of disease burden caused by malaria. The aim of this study was to determine the effectiveness of health education on the adoption of LLINs among pregnant women living in Tharparkar, a remote district in Sindh Province, Pakistan. Methods A quasi-experimental study design with control and intervention groups was conducted with 200 pregnant women (100 in each group). Women in the intervention group were provided with health education sessions on malaria for 12 weeks, while those in the control group obtained routine information from lady health workers (LHWs). Pre- and post-intervention assessment was done of knowledge about malaria and use of LLIN, which was statistically analysed using descriptive statistics and difference in difference (DID) multivariable regression analysis to test effectiveness of the intervention. Results Baseline was conducted with 200 pregnant women. Demographic characteristics were similar in both groups with slight differences in age, education, income, type of latrine, and source of drinking water. There were no significant differences between mean knowledge and use of LLINs scores between groups at baseline. However, the estimated DID value after the intervention was 4.170 (p < 0.01) and represents an increase in scores of knowledge in the intervention group compared to control. Similarly DID value of 3.360 (p < 0.05) showed an increase in use of LLINs score after the intervention which was significant, showing that the intervention had a positive effect. Conclusions Results proved that health education could be an effective intervention for improving knowledge and usage of LLINs among pregnant women for the prevention of malaria. Such educational interventions have a positive potential to be implemented at larger scale by incorporating them into routine health sessions provided by health workers.
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Affiliation(s)
- Ramesh Kumar
- Health Services Academy, Ministry of National Health Services Regulation & Coordination, Government of Pakistan, Islamabad, Pakistan. .,College of Public Health Sciences, Chulalongkorn University, Bangkok, Thailand.
| | - Midhat Farzeen
- Health Services Academy, Ministry of National Health Services Regulation & Coordination, Government of Pakistan, Islamabad, Pakistan
| | - Assad Hafeez
- Health Services Academy, Ministry of National Health Services Regulation & Coordination, Government of Pakistan, Islamabad, Pakistan
| | - Baseer Khan Achakzai
- Directorate of Malaria, Ministry of National Health Services Regulation & Coordination, Government of Pakistan, Islamabad, Pakistan
| | - Muskan Vankwani
- Dow international Medical College Karachi, Karachi, Pakistan
| | - Manohar Lal
- Federal Government Polyclinic Postgraduate Institute, Islamabad, Pakistan
| | - Rabia Iqbal
- Federal Government Polyclinic Postgraduate Institute, Islamabad, Pakistan
| | - Ratana Somrongthong
- College of Public Health Sciences, Chulalongkorn University, Bangkok, Thailand.
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Lawford HLS, Lee AC, Kumar S, Liley HG, Bora S. Establishing a conceptual framework of the impact of placental malaria on infant neurodevelopment. Int J Infect Dis 2019; 84:54-65. [PMID: 31028878 DOI: 10.1016/j.ijid.2019.04.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 04/12/2019] [Accepted: 04/18/2019] [Indexed: 01/11/2023] Open
Abstract
A novel conceptual framework to describe the relationship between placental malaria and adverse infant neurodevelopmental outcomes is proposed. This conceptual framework includes three distinct stages: (1) maternal and environmental risk factors for the development of placental malaria; (2) placental pathology and inflammation associated with placental malaria infection; and (3) postnatal impacts of placental malaria. The direct, indirect, and bidirectional effects of these risk factors on infant neurodevelopment across the three stages were critically examined. These factors ultimately culminate in an infant phenotype that not only leads to adverse birth outcomes, but also to increased risks of neurological, cognitive, and behavioural deficits that may impact the quality of life in this high-risk population. Multiple risk factors were identified in this conceptual framework; nonetheless, based on current evidence, a key knowledge gap is the uncertainty regarding which are the most important and how exactly they interact.
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Affiliation(s)
- Harriet L S Lawford
- Mothers, Babies and Women's Health Program, Mater Research Institute, Faculty of Medicine, The University of Queensland, South Brisbane, QLD, Australia
| | - Anne Cc Lee
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Sailesh Kumar
- Mothers, Babies and Women's Health Program, Mater Research Institute, Faculty of Medicine, The University of Queensland, South Brisbane, QLD, Australia
| | - Helen G Liley
- Mothers, Babies and Women's Health Program, Mater Research Institute, Faculty of Medicine, The University of Queensland, South Brisbane, QLD, Australia
| | - Samudragupta Bora
- Mothers, Babies and Women's Health Program, Mater Research Institute, Faculty of Medicine, The University of Queensland, South Brisbane, QLD, Australia.
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Niikura M, Inoue S, Mineo S, Asahi H, Kobayashi F. IFNGR1 signaling is associated with adverse pregnancy outcomes during infection with malaria parasites. PLoS One 2017; 12:e0185392. [PMID: 29117241 PMCID: PMC5678718 DOI: 10.1371/journal.pone.0185392] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 09/12/2017] [Indexed: 11/19/2022] Open
Abstract
Complicated/severe cases of placental pathology due to Plasmodium falciparum and P. vivax, especially adverse pregnancy outcomes during P. vivax infection, have been increasing in recent years. However, the pathogenesis of placental pathology during severe malaria is poorly understood, while responses against IFN-γ are thought to be associated with adverse pregnancy outcomes. In the present study, we explored the role of IFN-γ receptor 1 (IFNGR1) signaling in placental pathology during severe malaria using luciferase-expressing rodent malaria parasites, P. berghei NK65 (PbNK65L). We detected luciferase activities in the lung, spleen, adipose tissue, and placenta in pregnant mice, suggesting that infected erythrocytes could accumulate in various organs during infection. Importantly, we found that fetal mortality in IFNGR1-deficient mice infected with PbNK65L parasites was much less than in infected wild type (WT) mice. Placental pathology was also improved in IFNGR1-deficient mice. In contrast, bioluminescence imaging showed that parasite accumulation in the placentas of IFNGR1-deficient pregnant mice was comparable to that in WT mice infected with PbNK65L. These findings suggest that IFNGR1 signaling plays a pivotal role in placental pathology and subsequent adverse pregnancy outcomes during severe malaria. Our findings may increase our understanding of how disease aggravation occurs during malaria during pregnancy.
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Affiliation(s)
- Mamoru Niikura
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
| | - Shin–Ichi Inoue
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
| | - Shoichiro Mineo
- Department of Molecular Pathology, Tokyo Medical University, Tokyo, Japan
| | - Hiroko Asahi
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
| | - Fumie Kobayashi
- Department of Infectious Diseases, Kyorin University School of Medicine, Tokyo, Japan
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Carvalho TG, Morahan B, John von Freyend S, Boeuf P, Grau G, Garcia-Bustos J, Doerig C. The ins and outs of phosphosignalling in Plasmodium: Parasite regulation and host cell manipulation. Mol Biochem Parasitol 2016; 208:2-15. [PMID: 27211241 DOI: 10.1016/j.molbiopara.2016.05.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 05/16/2016] [Indexed: 12/15/2022]
Abstract
Signal transduction and kinomics have been rapidly expanding areas of investigation within the malaria research field. Here, we provide an overview of phosphosignalling pathways that operate in all stages of the Plasmodium life cycle. We review signalling pathways in the parasite itself, in the cells it invades, and in other cells of the vertebrate host with which it interacts. We also discuss the potential of these pathways as novel targets for antimalarial intervention.
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Affiliation(s)
- Teresa Gil Carvalho
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Belinda Morahan
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Simona John von Freyend
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Philippe Boeuf
- Burnet Institute, Melbourne, Victoria 3004, Australia; The University of Melbourne, Department of Medicine, Melbourne, Victoria 3010, Australia; Victorian Infectious Diseases Service, Royal Melbourne Hospital, Melbourne, Victoria 3010, Australia
| | - Georges Grau
- Vascular Immunology Unit, Department of Pathology, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2050, Australia
| | - Jose Garcia-Bustos
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Christian Doerig
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Victoria 3800, Australia.
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Fana SA, Bunza MDA, Anka SA, Imam AU, Nataala SU. Prevalence and risk factors associated with malaria infection among pregnant women in a semi-urban community of north-western Nigeria. Infect Dis Poverty 2015; 4:24. [PMID: 26269742 PMCID: PMC4534061 DOI: 10.1186/s40249-015-0054-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 04/13/2015] [Indexed: 11/20/2022] Open
Abstract
Background Malaria during pregnancy remains a serious public health problem, with substantial risks for the mother, her foetus and the newborn. The aim of this study was to determine the prevalence of malaria and possible risk factors for malaria infection among pregnant women in a semi-urban area in north-western Nigeria. Pregnant women are among the most susceptible to malaria infection. Knowledge of their malaria infection status is an important yardstick to measure the effectiveness of any malaria control programme. Methods We conducted a cross sectional study in the semi-urban area of Argungu, Kebbi State Nigeria. Two hundred and fifty five pregnant women were included in the study after informed verbal consent was obtained. For each participant, the socio-demographic profile, stage of pregnancy and attitude to the use of insecticide- treated nets (ITNs) were investigated using a questionnaire. Peripheral blood samples were collected and thick blood smears were prepared and stained with Giemsa stains to check for malaria parasitaemia. The associations between age, education level and use of ITNs with occurrence of malaria infection during pregnancy were analysed using the chi-square test. Results One hundred and six (41.6%) out of 255 pregnant women were infected with malaria parasites, with a mean parasite density of 800 parasitesμl−1. It was found that prevalence and parasite density decreased as age increased. The chi-square test indicated that a lack of education and non-usage of ITNs were significantly associated with malaria infection. Conclusion Malaria is still a major public health issue among pregnant women mainly due to illiteracy and non -compliance to using ITNs. Increasing awareness about malaria preventive measures and early attendance of antenatal care services will help to reduce malaria and, consequently, its associated morbidities and mortalities. Electronic supplementary material The online version of this article (doi:10.1186/s40249-015-0054-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sani Abdullahi Fana
- Department of Medical Microbiology, Faculty of Medical Laboratory Science, UsmanuDanfodiyo University, Sokoto, Nigeria
| | | | - Sule Aliyu Anka
- Department of Biological Sciences, UsmanuDanfodiyo University, Sokoto, Nigeria
| | - Asiya Umar Imam
- Department of Medical Microbiology, Faculty of Medical Laboratory Science, UsmanuDanfodiyo University, Sokoto, Nigeria
| | - Shehu Usman Nataala
- Department of Medical Microbiology, Faculty of Medical Laboratory Science, UsmanuDanfodiyo University, Sokoto, Nigeria
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Rabiu KA, Davies NO, Nzeribe-Abangwu UO, Adewunmi AA, Akinlusi FM, Akinola OI, Ogundele SO. Malaria prevention and treatment in pregnancy: survey of current practice among private medical practitioners in Lagos, Nigeria. Trop Doct 2014; 45:6-11. [PMID: 25253668 DOI: 10.1177/0049475514550061] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We studied the practice of malaria prevention and treatment in pregnancy of 394 private medical practitioners in Lagos State, Nigeria using a self-administered pre-tested structured questionnaire. Only 39 (9.9%) respondents had correct knowledge of the World Health Organization (WHO) strategies. Malaria prophylaxis in pregnancy was offered by 336 (85.3%), but only 98 (24.9%) had correct knowledge of recommended chemoprophylaxis. Of these, 68 (17.3%) had correct knowledge of first trimester treatment, while only 41 (10.4%) had knowledge of second and third trimester treatment. Only 64 (16.2%) of respondents routinely recommended use of insecticide-treated bed nets. The most common anti-malarial drug prescribed for chemoprophylaxis was pyrimethamine (43.7%); chloroquine was the most common anti-malarial prescribed for both first trimester treatment (81.5%) and second and third trimester treatment (55.3%). The study showed that private medical practitioners have poor knowledge of malaria prophylaxis and treatment in pregnancy, and the practice of most do not conform to recommended guidelines.
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Affiliation(s)
- Kabiru Afolarin Rabiu
- FWACS FMCOG, Department of Obstetrics and Gynaecology, Lagos State University College of Medicine, Ikeja, Lagos State, Nigeria
| | - Nosimot Omolola Davies
- MB;BS MPH, Department of Haematology and Blood Transfusion, Lagos University Teaching Hospital, Idi-Araba, Lagos State, Nigeria
| | - Ugochi O Nzeribe-Abangwu
- MB;BS FWACS, Department of Obstetrics and Gynaecology, Lagos State University Teaching Hospital, Ikeja, Lagos State, Nigeria
| | - Adeniyi Abiodun Adewunmi
- FWACS FICS, Department of Obstetrics and Gynaecology, Lagos State University College of Medicine, Ikeja, Lagos State, Nigeria
| | - Fatimat Motunrayo Akinlusi
- MB;ChB FWACS, Department of Obstetrics and Gynaecology, Lagos State University College of Medicine, Ikeja, Lagos State, Nigeria
| | - Oluwarotimi Ireti Akinola
- FWACS FICS, Department of Obstetrics and Gynaecology, Lagos State University College of Medicine, Ikeja, Lagos State, Nigeria
| | - Sunday O Ogundele
- MSc FMCP, Department of Pharmacology, Lagos State University College of Medicine, Ikeja, Lagos State, Nigeria
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Madadi P, Enato EFO, Walfisch A. Actionable theranostics for global maternal health: a focus on HIV and malaria. Expert Rev Mol Diagn 2014; 12:831-40. [DOI: 10.1586/erm.12.118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Chandrasiri UP, Chua CLL, Umbers AJ, Chaluluka E, Glazier JD, Rogerson SJ, Boeuf P. Insight Into the Pathogenesis of Fetal Growth Restriction in Placental Malaria: Decreased Placental Glucose Transporter Isoform 1 Expression. J Infect Dis 2013; 209:1663-7. [DOI: 10.1093/infdis/jit803] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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A model of parity-dependent immunity to placental malaria. Nat Commun 2013; 4:1609. [PMID: 23511473 PMCID: PMC3615483 DOI: 10.1038/ncomms2605] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 02/14/2013] [Indexed: 11/08/2022] Open
Abstract
Plasmodium falciparum placental infection during pregnancy is harmful for both mother and child. Protection from placental infection is parity-dependent, that is, acquired over consecutive pregnancies. However, the infection status of the placenta can only be assessed at delivery. Here, to better understand the mechanism underlying this parity-dependence, we fitted a model linking malaria dynamics within the general population to observed placental histology. Our results suggest that immunity resulting in less prolonged infection is a greater determinant of the parity-specific patterns than immunity that prevents placental sequestration. Our results also suggest the time when maternal blood first flows into the placenta is a high-risk period. Therefore, preventative strategies implementable before or early in pregnancy, such as insecticide-treated net usage in women of child-bearing age or any future vaccine, could substantially reduce the number of women who experience placental infection.
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Agomo CO, Oyibo WA. Factors associated with risk of malaria infection among pregnant women in Lagos, Nigeria. Infect Dis Poverty 2013; 2:19. [PMID: 24001135 PMCID: PMC3848704 DOI: 10.1186/2049-9957-2-19] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 08/28/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pregnant women living in an area of stable malaria transmission such as Lagos, Nigeria, have been identified as being at an increased risk of the effects of malaria infection. In this area, most of the infections are asymptomatic which means they are overlooked and untreated much to the detriment of the mother and her foetus. The reality of scaled-up malaria interventions with long-lasting insecticide treated nets, vector control, artemisinin combination therapy (ACT) and intermittent preventive treatment of malaria pregnancy (IPTp) using sulphadoxine pyrimethamine (SP) is that it is also essential to determine the risk factors at play in these kinds of circumstances. This study was aimed at identifying the factors associated with risk of malaria infection in pregnant women in Lagos, Southwest Nigeria. METHODS Demographic information and malaria prevention practices of the pregnant women studied were captured using structured questionnaire. Microscopy was used to establish malaria infection, species identification and parasite density. Relative risk and multivariate logistic regression analysis were used to compare factors associated with malaria in pregnant women. RESULTS Malaria microscopy details, demographic information and malaria prevention practices of the pregnant women were obtained using a structured questionnaire. The prevalence of malaria using peripheral blood from 1,084 pregnant women that participated in the study was 7.7%. Plasmodium falciparum (P. falciparum) was seen in 95.2% of the cases as either mixed infection with P. malariae (3.6%) or as a mono infection (91.6%). Malaria preventive practices associated with a significant reduction (P<0.05) in the malaria infection was the use of insecticide sprays (RR = 0.36, 95 C.I. 0.24-0.54), and the combined use of insecticide spray and insecticide-treated nets (ITN) (RR= 6.53, 95% C.I. 0.92-46.33). Sleeping under ITN alone (RR = 1.07, 95% C.I. 0.55-2.09) was not associated with significant reduction in malaria infection among the study participants with malaria parasitaemia. Young maternal age (<20years) (RR = 2.86, 95% C.I. 1.48 - 5.50), but not primigravidity (RR = 1.36, 95% C.I. 0.90-2.05), was associated with an increased risk of malaria infection during pregnancy. After a multivariate logistic regression, young maternal age (OR = 2.61, 95% C.I. 1.13 - 6.03) and the use of insecticide spray (OR = 0.38, 95% C.I. 0.24-0.63) were associated with an increase and a reduction in malaria infection, respectively. CONCLUSION Malaria prevalence was low among the pregnant women studied. Young maternal age and non-usage of insecticidal spray were the main factors associated with an increased risk of malaria infection among pregnant women in Lagos, Nigeria.
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Affiliation(s)
- Chimere O Agomo
- ANDI Centre of Excellence for Malaria Diagnosis, International Malaria, Microscopy Training and RDT QA Programme, WHO/TDR/FIND Malaria Specimen Bank Site, Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria
- Malaria Research Laboratory, Nigerian Institute of Medical Research, PMB 2013, Yaba, Lagos, Nigeria
| | - Wellington A Oyibo
- ANDI Centre of Excellence for Malaria Diagnosis, International Malaria, Microscopy Training and RDT QA Programme, WHO/TDR/FIND Malaria Specimen Bank Site, Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria
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15
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Malaria modifies neonatal and early-life toll-like receptor cytokine responses. Infect Immun 2013; 81:2686-96. [PMID: 23690399 DOI: 10.1128/iai.00237-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Protection from infections in early life relies extensively on innate immunity, but it is unknown whether and how maternal infections modulate infants' innate immune responses, thereby altering susceptibility to infections. Plasmodium falciparum causes pregnancy-associated malaria (PAM), and epidemiological studies have shown that PAM enhances infants' susceptibility to infection with P. falciparum. We investigated how PAM-mediated exposures in utero affect innate immune responses and their relationship with infection in infancy. In a prospective study of mothers and their babies in Benin, we investigated changes in Toll-like receptor (TLR)-mediated cytokine responses related to P. falciparum infections. Whole-blood samples from 134 infants at birth and at 3, 6, and 12 months of age were stimulated with agonists specific for TLR3, TLR4, TLR7/8, and TLR9. TLR-mediated interleukin 6 (IL-6) and IL-10 production was robust at birth and then stabilized, whereas tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ) responses were weak at birth and then increased. In multivariate analyses, maternal P. falciparum infections at delivery were associated with significantly higher TLR3-mediated IL-6 and IL-10 responses in the first 3 months of life (P < 0.05) and with significantly higher TLR3-, TLR7/8-, and TLR9-mediated TNF-α responses between 6 and 12 months of age (P < 0.05). Prospective analyses showed that higher TLR3- and TLR7/8-mediated IL-10 responses at birth were associated with a significantly higher risk of P. falciparum infection in infancy (P < 0.05). Neonatal and infant intracellular TLR-mediated cytokine responses are conditioned by in utero exposure through PAM late in pregnancy. Enhanced TLR-mediated IL-10 responses at birth are associated with an increased risk of P. falciparum infection, suggesting a compromised ability to combat infection in early life.
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The impact of placental malaria on neurodevelopment of exposed infants: a role for the complement system? Trends Parasitol 2013; 29:213-9. [DOI: 10.1016/j.pt.2013.03.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/08/2013] [Accepted: 03/11/2013] [Indexed: 01/01/2023]
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17
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Boeuf P, Aitken EH, Chandrasiri U, Chua CLL, McInerney B, McQuade L, Duffy M, Molyneux M, Brown G, Glazier J, Rogerson SJ. Plasmodium falciparum malaria elicits inflammatory responses that dysregulate placental amino acid transport. PLoS Pathog 2013; 9:e1003153. [PMID: 23408887 PMCID: PMC3567154 DOI: 10.1371/journal.ppat.1003153] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 11/21/2012] [Indexed: 01/09/2023] Open
Abstract
Placental malaria (PM) can lead to poor neonatal outcomes, including low birthweight due to fetal growth restriction (FGR), especially when associated with local inflammation (intervillositis or IV). The pathogenesis of PM-associated FGR is largely unknown, but in idiopathic FGR, impaired transplacental amino acid transport, especially through the system A group of amino acid transporters, has been implicated. We hypothesized that PM-associated FGR could result from impairment of transplacental amino acid transport triggered by IV. In a cohort of Malawian women and their infants, the expression and activity of system A (measured by Na+-dependent 14C-MeAIB uptake) were reduced in PM, especially when associated with IV, compared to uninfected placentas. In an in vitro model of PM with IV, placental cells exposed to monocyte/infected erythrocytes conditioned medium showed decreased system A activity. Amino acid concentrations analyzed by reversed phase ultra performance liquid chromatography in paired maternal and cord plasmas revealed specific alterations of amino acid transport by PM, especially with IV. Overall, our data suggest that the fetoplacental unit responds to PM by altering its placental amino acid transport to maintain adequate fetal growth. However, IV more profoundly compromises placental amino acid transport function, leading to FGR. Our study offers the first pathogenetic explanation for FGR in PM. Malaria infection during pregnancy can cause fetal growth restriction and low birthweight associated with high infant mortality and morbidity rates. The pathogenesis of fetal growth restriction in placental malaria is largely unknown, but in other pathological pregnancies, impaired transplacental amino acid transport has been implicated. In a cohort of Malawian women and their infants, we found that placental malaria, especially when associated with local inflammation, was associated with decreased expression and activity of an important group of amino acid placental transporters. Using an in vitro model of placental malaria with local inflammation, we discovered that maternal monocyte products could impair the activity of amino acid transporters on placental cells. Amino acid concentrations in paired maternal and cord plasmas revealed specific alterations of amino acid transport by placental malaria, especially with local inflammation. Overall, our data suggest that, more than malaria infection per se, the local inflammation it triggers compromises placental amino acid transport function, leading to fetal growth restriction. Greater understanding of the mechanisms involved, combined with interventions to improve fetal growth in malaria, are important priorities in areas of the world where the co-existence of malaria and maternal malnutrition threatens the health and lives of millions of young babies.
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Affiliation(s)
- Philippe Boeuf
- The University of Melbourne, Department of Medicine-RMH, Parkville, Victoria, Australia.
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18
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Monocytes and macrophages in malaria: protection or pathology? Trends Parasitol 2012; 29:26-34. [PMID: 23142189 DOI: 10.1016/j.pt.2012.10.002] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 10/12/2012] [Accepted: 10/16/2012] [Indexed: 02/07/2023]
Abstract
Recruitment and activation of monocytes and macrophages are essential for clearance of malaria infection, but these have also been associated with adverse clinical outcomes. In this review we discuss recent discoveries on how distinct molecular interactions between monocytes, macrophages, and malaria parasites may alter the balance between protection and pathology in malaria-infected individuals. The immunopathology of severe malaria often originates from excessive immune activation by parasites. The involvement of monocytes and macrophages in these events is highlighted, and priorities for future research to clarify the roles of these cells in malaria are proposed. Knowledge of the factors influencing the balance between protection and pathology can assist in the design of therapeutics aimed at modulating monocyte and macrophage functions to improve outcomes.
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Stolp H, Neuhaus A, Sundramoorthi R, Molnár Z. The Long and the Short of it: Gene and Environment Interactions During Early Cortical Development and Consequences for Long-Term Neurological Disease. Front Psychiatry 2012; 3:50. [PMID: 22701439 PMCID: PMC3372875 DOI: 10.3389/fpsyt.2012.00050] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 05/01/2012] [Indexed: 01/21/2023] Open
Abstract
Cortical development is a complex amalgamation of proliferation, migration, differentiation, and circuit formation. These processes follow defined timescales and are controlled by a combination of intrinsic and extrinsic factors. It is currently unclear how robust and flexible these processes are and whether the developing brain has the capacity to recover from disruptions. What is clear is that there are a number of cognitive disorders or conditions that are elicited as a result of disrupted cortical development, although it may take a long time for the full pathophysiology of the conditions to be realized clinically. The critical window for the manifestation of a neurodevelopmental disorder is prolonged, and there is the potential for a complex interplay between genes and environment. While there have been extended investigations into the genetic basis of a number of neurological and mental disorders, limited definitive associations have been discovered. Many environmental factors, including inflammation and stress, have been linked to neurodevelopmental disorders, and it may be that a better understanding of the interplay between genes and environment will speed progress in this field. In particular, the development of the brain needs to be considered in the context of the whole materno-fetal unit as the degree of the metabolic, endocrine, or inflammatory responses, for example, will greatly influence the environment in which the brain develops. This review will emphasize the importance of extending neurodevelopmental studies to the contribution of the placenta, vasculature, cerebrospinal fluid, and to maternal and fetal immune response. These combined investigations are more likely to reveal genetic and environmental factors that influence the different stages of neuronal development and potentially lead to the better understanding of the etiology of neurological and mental disorders such as autism, epilepsy, cerebral palsy, and schizophrenia.
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Affiliation(s)
- Helen Stolp
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
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20
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Agomo CO, Oyibo WA, Odukoya-Maije F. Parasitologic Assessment of Two-Dose and Monthly Intermittent Preventive Treatment of Malaria during Pregnancy with Sulphadoxine-Pyrimethamine (IPTP-SP) in Lagos, Nigeria. Malar Res Treat 2011; 2011:932895. [PMID: 22312575 PMCID: PMC3265291 DOI: 10.4061/2011/932895] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 08/10/2011] [Accepted: 08/30/2011] [Indexed: 11/20/2022] Open
Abstract
Intermittent preventive treatment of malaria with sulphadoxine-pyrimethamine (IPTP-SP) is a key strategy in the control of malaria in pregnancy. However, reports of increasing level of resistance to SP using nonpregnant populations have made it imperative for the continuous monitoring of the efficacy of SP in pregnant women. This study assessed using microscopy, monthly dosing and the standard two-dose regimen among 259 pregnant women attending antenatal clinics in Lagos, Nigeria that consented 122 in the two-dose arm (Arm A) and 137 in the monthly dose arm (Arm B). Baseline parasitaemia in the two groups was 5 (4.1%) and 3 (2.2%) in Arms A and B, respectively. Few of the women developed parasitaemia after the initial SP dose in Arms A 4 (3.3%) and B 2 (1.5%). However, none of the women had malaria infection after the second dose in both Arms. Although IPTP-SP is suggestive of protecting the women from malaria infection, there was no significant difference observed between the two dosing schemes.
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Affiliation(s)
- Chimere O. Agomo
- Tropical Diseases Laboratory, Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Lagos, Nigeria
- Malaria Research Laboratory, Department of Biochemistry, Nigerian Institute of Medical Research, P.M.B 2013 Yaba, Lagos, Nigeria
| | - Wellington A. Oyibo
- Tropical Diseases Laboratory, Department of Medical Microbiology and Parasitology, College of Medicine, University of Lagos, Lagos, Nigeria
| | - Funke Odukoya-Maije
- Department of Obstetrics and Gynaecology, Ajeromi General Hospital, Ajegunle, Lagos, Nigeria
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21
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Huynh BT, Fievet N, Gbaguidi G, Dechavanne S, Borgella S, Guézo-Mévo B, Massougbodji A, Ndam NT, Deloron P, Cot M. Influence of the timing of malaria infection during pregnancy on birth weight and on maternal anemia in Benin. Am J Trop Med Hyg 2011; 85:214-20. [PMID: 21813837 DOI: 10.4269/ajtmh.2011.11-0103] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Abstract. Although consequences of malaria in pregnancy are well known, the period of pregnancy in which infection has the highest impact is still unclear. In Benin, we followed up a cohort of 1,037 women through pregnancy until delivery. The objective was to evaluate the relationship between the timing of infection and birth weight, and maternal anemia at delivery. At the beginning of pregnancy, peripheral infections were associated with a decrease in mean birth weight (-98.5 g; P = 0.03) and an increase in the risk of anemia at delivery (adjusted odds ratio [aOR] = 1.6; P = 0.03). Infections in late pregnancy were related to a higher risk of maternal anemia at delivery (aOR = 1.7; P = 0.001). To fully protect the women during the whole pregnancy, already implemented measures (insecticide-treated nets and intermittent preventive treatment) should be reinforced. In the future, a vaccine against pregnancy-associated malaria parasites could protect the women in early pregnancy, which seems to be a high-risk period.
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Affiliation(s)
- Bich-Tram Huynh
- Institut de Recherche pour le Développement, Mère et Enfant Face aux Infections Tropicales, Paris, France.
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Umbers AJ, Aitken EH, Rogerson SJ. Malaria in pregnancy: small babies, big problem. Trends Parasitol 2011; 27:168-75. [PMID: 21377424 DOI: 10.1016/j.pt.2011.01.007] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 01/24/2011] [Accepted: 01/27/2011] [Indexed: 11/28/2022]
Abstract
Placental malaria is hypothesized to lead to placental insufficiency, which causes fetal growth restriction (FGR). In this review, recent discoveries regarding the mechanisms of pathogenesis by which malaria causes FGR are discussed in the wider context of placental function and fetal growth. Placental malaria and associated host responses can induce changes in placental structure and function, affecting pregnancy-associated growth-regulating hormones and predisposing the offspring to hypertension and vascular dysfunction. Risk factors associated with FGR are highlighted, and potential interventions and studies to uncover remaining mechanisms of pathogenesis are proposed. Together, these strategies aim to decrease the burden of FGR associated with malaria in pregnancy.
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Affiliation(s)
- Alexandra J Umbers
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Post Office Royal Melbourne Hospital, Parkville, VIC 3050, Australia
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Dhangadamajhi G, Kar SK, Ranjit M. The survival strategies of malaria parasite in the red blood cell and host cell polymorphisms. Malar Res Treat 2010; 2010:973094. [PMID: 22332025 PMCID: PMC3277829 DOI: 10.4061/2010/973094] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 07/07/2010] [Indexed: 11/20/2022] Open
Abstract
Parasite growth within the erythrocyte causes dramatic alterations of host cell which on one hand facilitates nutrients acquisition from extracellular environment and on other hand contributes to the symptoms of severe malaria. The current paper focuses on interactions between the Plasmodium parasite and its metabolically highly reduced host cell, the natural selection of numerous polymorphisms in the genes encoding hemoglobin and other erythrocyte proteins.
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Affiliation(s)
- Gunanidhi Dhangadamajhi
- Regional Medical Research Centre, Indian Council of Medical Research, Chandrasekharpur, Bhubaneswar 751023, India
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Wellems TE, Hayton K, Fairhurst RM. The impact of malaria parasitism: from corpuscles to communities. J Clin Invest 2009; 119:2496-505. [PMID: 19729847 DOI: 10.1172/jci38307] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Malaria continues to exert a tremendous health burden on human populations, reflecting astonishingly successful adaptations of the causative Plasmodium parasites. We discuss here how this burden has driven the natural selection of numerous polymorphisms in the genes encoding hemoglobin and other erythrocyte proteins and some effectors of immunity. Plasmodium falciparum, the most deadly parasite species in humans, displays a vigorous system of antigen variation to counter host defenses and families of functionally redundant ligands to invade human cells. Advances in genetics and genomics are providing fresh insights into the nature of these evolutionary adaptations, processes of parasite transmission and infection, and the difficult challenges of malaria control.
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Affiliation(s)
- Thomas E Wellems
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland 20892-8132, USA.
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Agomo CO, Oyibo WA, Anorlu RI, Agomo PU. Prevalence of malaria in pregnant women in Lagos, South-West Nigeria. THE KOREAN JOURNAL OF PARASITOLOGY 2009; 47:179-83. [PMID: 19488427 DOI: 10.3347/kjp.2009.47.2.179] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 04/04/2009] [Accepted: 04/09/2009] [Indexed: 11/23/2022]
Abstract
Prevalence rates reported for malaria in pregnancy in Nigeria vary considerably. The accuracy of results of malaria diagnosis is dependent on training, experience, and motivation of the microscopist as well as the laboratory facility available. Results of training programmes on malaria microscopy have shown low levels of sensitivity and specificity of those involved in malaria diagnosis routinely and for research. This study was done to ascertain the true prevalence of malaria in pregnancy in Lagos, South-West Nigeria. A total of 1,084 pregnant women were recruited into this study. Blood smears stained with Giemsa were used for malaria diagnosis by light microscopy. Malaria infection during pregnancy presents mostly as asymptomatic infection. The prevalence of malaria in this population was 7.7% (95% confidence interval; 6.2-9.4%). Factors identified to increase the risk of malaria infection include young maternal age (< 20 years), and gravidity (primigravida). In conclusion, this study exposes the over-diagnosis of malaria in pregnancy and the need for training and retraining of laboratory staffs as well as establishing the malaria diagnosis quality assurance programme to ensure the accuracy of malaria microscopy results at all levels.
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Affiliation(s)
- Chimere O Agomo
- WHO/TDR Malaria Specimen Bank Collection Site, Tropical Diseases Research Laboratory, Department of Medical Microbiology and Parasitology, College of Medicine of the University of Lagos, Nigeria
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Flt1, pregnancy, and malaria: evolution of a complex interaction. Proc Natl Acad Sci U S A 2008; 105:14243-4. [PMID: 18801923 DOI: 10.1073/pnas.0807932105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Anders K, Marchant T, Chambo P, Mapunda P, Reyburn H. Timing of intermittent preventive treatment for malaria during pregnancy and the implications of current policy on early uptake in north-east Tanzania. Malar J 2008; 7:79. [PMID: 18471279 PMCID: PMC2396646 DOI: 10.1186/1475-2875-7-79] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Accepted: 05/09/2008] [Indexed: 11/10/2022] Open
Abstract
Background Intermittent preventive treatment (IPTp) is efficacious in reducing the adverse outcomes associated with pregnancy-associated malaria, however uptake of the recommended two doses is low in Tanzania, and little is known of the timepoint during pregnancy at which it is delivered. This study investigated the timing of delivery of IPTp to pregnant women attending antenatal clinics (ANC), and the potential determinants of timely uptake. Methods Structured interviews were conducted with staff and pregnant women at antenatal clinics in northeast Tanzania, and antenatal consultations were observed. Facility-based and individual factors were analysed for any correlation with timing of IPTp uptake. Results Almost half the women interviewed first attended ANC during or before the fourth month of gestation, however 86% of these early attendees did not receive IPTp on their first visit. The timing of IPTp delivery complied closely with the national guidelines which stipulate giving the first dose at 20–24 weeks gestation. Uptake of at least one dose of IPTp among women who had reached this gestation age was 67%, although this varied considerably between clinics. At one facility, IPTp was not delivered because SP was out of stock. Conclusion Early uptake of IPTp was found to be hampered by factors external to health worker performance or women's individual preferences. These include insufficient drug stocks and an apparent lack of information to health workers on the reasoning for continued use of SP for IPTp when it has been replaced as a first-line treatment. In addition, an unexpectedly high proportion of women attend antenatal clinics before 20 weeks of pregnancy. While current policy denies the use of IPTp at this time, there is emerging, but incomplete, evidence that malaria in early pregnancy may contribute considerably to the burden of pregnancy-related malaria. Current policy may thus result in a missed opportunity for maximising the benefit of this intervention, and efforts to encourage earlier attendance at ANC alone are unlikely to improve uptake of IPTp. More evidence is needed to weigh the benefits of early IPTp use against theoretical risks of antifolate drugs in early pregnancy.
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Affiliation(s)
- Katherine Anders
- London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK.
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Hot, sweet and sticky: the glycobiology of Plasmodium falciparum. Trends Parasitol 2008; 24:210-8. [DOI: 10.1016/j.pt.2008.02.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 02/02/2008] [Accepted: 02/05/2008] [Indexed: 11/22/2022]
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