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1.
Malar J ; 22(1): 154, 2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37179349

RESUMEN

BACKGROUND: In Nigeria, declining responsiveness to artemether-lumefantrine (AL), the artemisinin-based combination therapy (ACT) of choice since 2005, has been reported. Pyronaridine-artesunate (PA) is a newer fixed-dose ACT recently prequalified by the WHO for the treatment of uncomplicated falciparum malaria. However, PA data from the Nigerian pediatric population is scarce. Therefore, the efficacy and safety of PA and AL using the WHO 28-day anti-malarial therapeutic efficacy study protocol in Ibadan, southwest Nigeria, were compared. METHODS: In an open-labelled, randomized, controlled clinical trial, 172 children aged 3-144 months with a history of fever and microscopically confirmed uncomplicated Plasmodium falciparum malaria were enrolled in southwest Nigeria. Enrollees were randomly assigned to receive PA or AL at standard dosages according to body weight for 3 days. Venous blood was obtained for hematology, blood chemistry, and liver function tests on days 0, 3, 7, and 28 as part of the safety evaluation. RESULTS: 165 (95.9%) of the enrolled individuals completed the study. About half (52.3%; 90/172) of enrollees were male. Eighty-seven (50.6%) received AL, while 85 (49.4%) received PA. Day 28, adequate clinical and parasitological response for PA was 92.7% [(76/82) 95% CI 83.1, 95.9] and 71.1% [(59/83) 95% CI 60.4, 79.9] for AL (0.001). Fever and parasite clearance were similar in both groups. Two of six and eight of 24 parasite recurrences were observed among PA- and AL-treated children, respectively. PCR-corrected Day-28 cure rates for PA were 97.4% (76/78) and 88.1% (59/67) for AL (= 0.04) in the per-protocol population after new infections were censored. Hematological recovery at day 28 was significantly better among PA-treated patients (34.9% 2.8) compared to those treated with AL (33.1% 3.0) (0.002). Adverse events in both treatment arms were mild and similar to the symptoms of malaria infection. Blood chemistry and liver function tests were mostly within normal limits, with an occasional marginal rise. CONCLUSION: PA and AL were well-tolerated. PA was significantly more efficacious than AL in both the PCR-uncorrected and PCR-corrected per-protocol populations during this study. The results of this study support the inclusion of PA in the anti-malarial treatment guidelines in Nigeria. RETROSPECTIVE TRIAL REGISTRATION: Clinicaltrials.gov: NCT05192265.


Asunto(s)
Antimaláricos , Artemisininas , Malaria Falciparum , Humanos , Niño , Masculino , Lactante , Femenino , Antimaláricos/efectos adversos , Combinación Arteméter y Lumefantrina/uso terapéutico , Nigeria , Estudios Retrospectivos , Artemisininas/efectos adversos , Arteméter/uso terapéutico , Combinación de Medicamentos , Malaria Falciparum/tratamiento farmacológico , Etanolaminas/uso terapéutico , Resultado del Tratamiento , Fluorenos/efectos adversos
2.
Parasitol Res ; 122(2): 519-526, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36510009

RESUMEN

BACKGROUND: Microscopic evaluation of parasite clearance is the gold standard in antimalarial drug efficacy trials. However, the presence of sub-microscopic residual parasitemia after artemisinin-based combination therapy (ACT) needs to be investigated. METHODS: One hundred and twenty (AL: n = 60, PA: n = 60) days 3 and 14 dried blood spots, negative by microscopy were analysed for residual parasitemia using nested PCR. Isolates with residual parasitemia on days 3 and 14 were further genotyped with their corresponding day-0 isolates using merozoite surface proteins msp-1, msp-2, and glurp genes for allelic similarity. RESULTS: Persistent PCR-determined sub-microscopic residual parasitemia at day 3 post ACT treatment was 83.3 (AL) and 88.3% (PA), respectively (ρ = 0.600), while 63.6 and 36.4% (ρ = 0.066) isolates were parasitemic at day 14 for AL and PA, respectively. Microscopy-confirmed gametocytemia persisted from days 0 to 7 and from days 0 to 21 for AL and PA. When the alleles of day 3 versus day 0 were compared according to base pair sizes, 59% of parasites shared identical alleles for glurp, 36% each for 3D7 and FC27, while K1 was 77%, RO33 64%, and MAD20 23%, respectively. Similarly, day 14 versus day 0 was 36% (glurp), 64% (3D7), and 32% (FC27), while 73% (K1), 77% (RO33), and 41% (MAD20), respectively. CONCLUSION: The occurrence of residual parasitemia on days 3 and 14 following AL or PA treatment may be attributable to the presence of either viable asexual, gametocytes, or dead parasite DNAs, which requires further investigation.


Asunto(s)
Antimaláricos , Malaria Falciparum , Humanos , Antimaláricos/uso terapéutico , Plasmodium falciparum , Parasitemia/tratamiento farmacológico , Parasitemia/epidemiología , Parasitemia/parasitología , Prevalencia , Nigeria/epidemiología , Arteméter/uso terapéutico , Combinación Arteméter y Lumefantrina/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Proteína 1 de Superficie de Merozoito/genética
3.
J Trop Pediatr ; 68(4)2022 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-35895093

RESUMEN

BACKGROUND: Although the global malaria burden is decreasing, there are still concerns about overdiagnosis of malaria and the danger of misdiagnosis of non-malaria causes of fever. Clinicians continue to face the challenge of differentiating between these causes despite the introduction of malaria rapid diagnostic tests (mRDTs). AIM: To determine the prevalence and causes of non-malaria-caused fever in children in South-Western Nigeria. METHODS: Secondary analysis of data obtained to evaluate the effect of restricting antimalarial treatment to positive mRDT children in rural and urban areas of southwest Nigeria. Clinical examinations, laboratory tests for malaria parasites (including thick blood film and mRDT) and bacterial identification were performed on children aged 3-59 months (n = 511). The non-malaria group comprised febrile children who had both negative mRDT and microscopy results, while the malaria group included those who were positive for either mRDT or microscopy. We compared the causes of fever among children with non-malaria fever and those with malaria. RESULTS: The prevalence of non-malaria fever and bacteria-malaria co-infection was 37.2% and 2.0%, respectively. Non-malarial pathogens identified were viral (54.7%) and bacterial (32.1%) infections. The bacterial infections included bacteriaemia (2.7%), urinary tract infections (21.6%), skin infections (11.6%) and otitis media (2.6%). The leading bacterial isolates were Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus pneumoniae. CONCLUSION: The high prevalence and wide range of non-malarial infections reinforces the need for point-of-care tests to identify bacterial and viral infections to optimize the treatment of febrile illnesses in malaria-endemic areas.


Asunto(s)
Antimaláricos , Malaria , Antimaláricos/uso terapéutico , Niño , Pruebas Diagnósticas de Rutina/métodos , Fiebre/epidemiología , Fiebre/etiología , Humanos , Lactante , Malaria/complicaciones , Malaria/diagnóstico , Malaria/epidemiología , Resultados Negativos , Nigeria/epidemiología
4.
Parasitol Res ; 121(7): 1983-1992, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35522326

RESUMEN

Malaria, helminthiasis and HIV are widespread in developing countries taking a heavy toll on pregnant women. Due to similar environmental and human factors of transmission, they co-exist. The epidemiology and pathology of these diseases have been extensively studied but data on serum cytokine profile changes which is crucial in pregnancy is limited. The aim of this study was to evaluate the co-infections and their impact on peripheral blood cytokines. Blood and stool samples were collected from recruited 18-45-year-old pregnant women in different trimesters who were apparently healthy with no obvious complications in pregnancy. Pretested questionnaires were administered for personal and socio-demographic details. Malaria parasitemia in Giemsa-stained thick blood films was examined microscopically. Stool samples were screened for helminths using Kato-Katz method. Cytokine levels of TNF-α, IFN-γ, IL-1α, IL-2, IL-4, IL-6, IL-10, IL-12p70, IL-13 and IL-17 in 121 serum samples were determined using ELISA. Data were analysed using descriptive statistics and Mann-Whitney U test at α0.05. Relative to the single infections, there were significant reductions in IFN-γ and IL-13 in second and third trimesters respectively in those with Plasmodium and helminth co-infection. IFN-γ and IL-17 were elevated while IL-1α and IL-12p70 were reduced in co-infection of helminths and HIV. Co-infection of Plasmodium and HIV in second and third trimesters showed significant elevations in IL-1α, IL-10 and IL-17 while TNF-α, IL-4 and IL-12p70 were significantly reduced. HIV in pregnancy and its co-infection with Plasmodium resulted in significant distortions in the cytokine profile. However, helminth and its co-infection with Plasmodium or HIV produced less changes in the cytokine profile.


Asunto(s)
Coinfección , Infecciones por VIH , Helmintiasis , Helmintos , Malaria , Plasmodium , Adolescente , Adulto , Animales , Coinfección/epidemiología , Citocinas , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Helmintiasis/complicaciones , Helmintiasis/epidemiología , Helmintiasis/parasitología , Humanos , Interleucina-10 , Interleucina-13 , Interleucina-17 , Interleucina-4 , Parasitosis Intestinales , Malaria/complicaciones , Malaria/epidemiología , Malaria/parasitología , Persona de Mediana Edad , Nigeria/epidemiología , Embarazo , Mujeres Embarazadas , Prevalencia , Factor de Necrosis Tumoral alfa , Adulto Joven
5.
AIDS Res Hum Retroviruses ; 37(12): 922-929, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34074135

RESUMEN

There are about 2.1 million children infected with HIV globally and about 120,000 deaths annually. Nigeria has one of the highest rates of pediatric HIV infection globally. Pretreatment HIV drug resistance data inform the choice of first- and second-line antiretroviral therapy (ART) regimens. This study investigated the prevalence of HIV drug-resistant strains among ART-naive children in Ibadan, Nigeria. A total of 20 children aged <15 years were enrolled. Demographic, clinical, and laboratory data were documented. Total nucleic acid was extracted from blood samples after which amplification of HIV-1 pol gene was done using polymerase chain reaction. Amplified gene was sequenced using big dye sequencing method. The sequenced HIV-1 pol gene was typed and analyzed for identification of mutations indicative of drug resistance across the different classes of ART. HIV-1 RNA pol gene was successfully amplified in 12/20 (60%) children. All were identified as HIV-1 and the subtypes were G and CRF 02AG, recombinant of 02_AG/G and recombinant of 02_AG/A1. Drug-resistant mutations (DRMs) were identified in 4/12 (33%). Three out of the four mutations were identified as non-nucleoside reverse transcriptase inhibitors DRM (K103N), whereas the fourth had nucleoside reverse transcriptase inhibitors DRM (M184V). Results from this preliminary study show that drug resistance among ART-naive children is a problem in Ibadan. Pretreatment drug resistance testing is desirable in children before initiation of ART to guide effective treatment.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Niño , Farmacorresistencia Viral/genética , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , VIH-1/genética , Humanos , Mutación , Nigeria
6.
Int J MCH AIDS ; 10(1): 81-87, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33659096

RESUMEN

BACKGROUND OR OBJECTIVES: Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) is widespread in sub-Saharan Africa with similarity in geographical distribution of major pathogens of public health interest. The aim of this study was to assess the effect of malaria and helminths on CD4 count, hematocrit values and viral load among HIV-infected pregnant women. METHODS: One hundred and ninety-seven HIV-infected pregnant women aged 18-45 years were recruited from a registered HIV clinic and questionnaires were administered for socio-demographic details. Screening for malaria parasites in blood was through microscopy while helminths were identified in stool using Kato-Katz method. Hematocrit levels were determined through centrifugation of blood collected in capillary tubes. At the time of recruitment, most recent CD4 count and viral load was obtained from the patients' case notes. RESULTS: About three-quarters (73.6%) of the women had above primary school level of education while more than half (60.2%) were petty traders. The prevalence of malaria parasites in the blood samples was 24.9%, while 3% were infected with helminths. There was only a single case of malaria, helminths and HIV co-infection in the study group. Prevalence of anemia was 75.6% with eight cases (4.1%) of severe anemia. About 86.6% of the women with anemia had low CD4 count (χ2= 8.801, p=0.032). The mean CD4 count was significantly lower among those with co-infection of malaria and HIV. CONCLUSION AND GLOBAL HEALTH IMPLICATIONS: Malaria or helminth infection among HIV-infected women lowers the CD4 count and increases the viral load with little changes in hematocrit values. Routine screening of HIV-infected women for probable multiple infections will aid in improving their overall health and well-being.

8.
Ghana Med J ; 55(3): 198-205, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35950180

RESUMEN

Objectives: This study aimed to assess communities' perception and adoption of the evidenced-based malaria diagnosis and case management intervention targeted at under-five children. The effectiveness of trained Volunteer Community Health Workers (VCHWs) to diagnose malaria among under-five children using rapid diagnostic testing kit, provide treatment using Artemisinin Combination Therapy and rectal Artesunate were assessed. Design: A qualitative evaluation study was conducted in October 2015. Setting: Communities in the 6 rural wards in Ona-Ara Local Government Area, Oyo State Nigeria. Participants: Caregivers of under-five children, community-based frontline health workers, and community leaders selected using purposively sampling. Methods: Nine Focus Group Discussions and 15 Key Informant Interviews were conducted using a pre-tested guide. Data were subjected to thematic analysis. Results: It was disclosed that VCHWs promoted people's access to prompt and appropriate malaria treatment. The communities accepted the VCHWs; the reasons given for this included the following: effectiveness of VCHWs in case management of malaria; good inter-personal relationship with caregivers; and the positive health outcomes associated with services provided by them. In addition, community members expressed satisfaction with the VCHWs and provided them with all the support needed to function throughout the malaria case management intervention. The VCHWs considered the support as a great source of encouragement. Conclusions: The use of VCHWs to treat malaria was adjudged to be effective and considered acceptable to the communities. The adoption of the intervention and its integration into the primary health system by the government is advocated for in medically underserved rural communities. Funding: This work was supported by UNICEF/UNDP/World Bank/WHO Special Programme for Research & Training in Tropical Diseases, World Health Organization, Geneva, Switzerland (project ID: A80550 [Nigeria] through funds made available by the European Commission (FP7) for research to improve community access to health interventions in Africa.


Asunto(s)
Antimaláricos , Malaria , Antimaláricos/uso terapéutico , Manejo de Caso , Niño , Humanos , Malaria/diagnóstico , Malaria/tratamiento farmacológico , Nigeria , Satisfacción Personal , Población Rural
9.
J Vector Borne Dis ; 58(4): 311-316, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35381819

RESUMEN

BACKGROUND & OBJECTIVES: Alterations in plasma apolipoproteins in individuals with malaria infection and their potential roles in the pathogenesis are known but the link between the malaria parasite density and apolipoprotein A1 (apo-A1) level is insufficiently understood. This study was conducted to determine whether the plasma apo-A1 level is influenced by the degree of parasitaemia in malaria infections. METHODS: In a case-control study, a convenient sample of children aged 2-10 years with uncomplicated malaria cases (UMC), asymptomatic parasitaemia cases (APC) and healthy children without parasitaemia (HCP) was recruited. The cases consisted of 61 UMC and 21 APC, while the controls consisted of 24 HCP. Levels of apo-A1 was determined using immunoturbidimetric assay and compared among the different degrees of parasite density. RESULTS: Of the 82 participants with parasitaemia, density was ≤1000/µL in 12, 1001-10000/µL in 21 and >10000/µL in 49 children. There was significant difference among the mean values of apolipoprotein A1 of the three groups, viz: UMC [91.4 (95% CI: 81.3, 101.5) mg/dL], APC [67.0 (95% CI: 48.9, 84.9) mg/dL] and HCP [99.0 (95% CI: 76.6, 121.3) mg/dL], p=0.029. Post-hoc analysis revealed that the mean plasma level of apo-A1 in HCP was significantly higher than APC by 32.0±12.4 mg/dL and UMC by 7.5±4.2 mg/dL. However, there were no differences in the mean apolipoprotein A1 levels among the three groups of parasite density. INTERPRETATION & CONCLUSION: The presence of parasitaemia causes a remarkable reduction in apolipoprotein A1 level that was not influenced by the degree of parasitaemia.


Asunto(s)
Apolipoproteína A-I , Malaria , Parasitemia , Apolipoproteína A-I/sangre , Infecciones Asintomáticas , Estudios de Casos y Controles , Niño , Preescolar , Humanos , Malaria/parasitología , Nigeria
10.
Implement Sci ; 15(1): 13, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32131852

RESUMEN

BACKGROUND: In the context of task shifting, a promoted approach to healthcare delivery in resource-poor settings, trained community health workers (CHWs) have been shown to be effective in delivering quality care of malaria for febrile under-5 children. While their effectiveness has been documented, the fidelity of implementation (FOI) has not been adequately studied. By understanding and measuring whether an intervention has been performed with fidelity, researchers and practitioners gain a better understanding of how and why an intervention works, and the extent to which outcomes can be improved. The objective of this study was to assess the FOI of a recommended protocol for malaria care by CHWs in a resource-poor setting in Nigeria. METHODS: Thirty-five female CHWs who participated in a 3-day training on home management of malaria among under-5 children were studied. They managed 1,646 children over the implementation period and then underwent evaluation via a one-time hospital-based observation by the trainers. During the evaluation, a pre-tested standard checklist was used to compute performance scores for CHWs; doctors and nurses were selected to serve as the gold standard for comparison. Performance scores (PS) recorded during the evaluation were used to assess adherence and compliance with the recommended treatment protocol. RESULTS: Of the 4 skill domains assessed, adherence was greatest for compliance with malaria treatment recommendations (94%) and lowest for post-treatment initiation counseling of home-based caregivers (69%). The average overall adherence of 83% was comparable to adherence by gold standard comparators. Mean PS was not found to be significantly associated with CHW demographics. Scores for clinical evaluation among those whose occupation was not healthcare-related were significantly lowered by 0.52 [95% CI (1.05-0.01), p = 0.05]. Compliance with the treatment protocol increased by 23% for every unit increase in total PS (p = 0.07) and doubled for every unit increase in scores for post-treatment initiation counseling of caregivers (p = 0.002). CONCLUSIONS: Studying intervention fidelity stands to identify the shortcomings of implementation and specific areas to target for improvement in future adoption or implementation. This study concludes that future trainings should emphasize clinical evaluation and post-treatment counseling of caregivers by CHWs to ensure the best outcome for children.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Protocolos Clínicos/normas , Agentes Comunitarios de Salud/normas , Malaria/tratamiento farmacológico , Adulto , Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Cuidadores/educación , Preescolar , Consejo/métodos , Quimioterapia Combinada , Evaluación del Rendimiento de Empleados/normas , Femenino , Humanos , Ciencia de la Implementación , Lactante , Capacitación en Servicio/organización & administración , Malaria/terapia , Técnicas Microbiológicas/métodos , Persona de Mediana Edad , Nigeria , Factores Socioeconómicos
11.
Microorganisms ; 8(2)2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31979279

RESUMEN

Malaria remains a significant disease, causing epic health problems and challenges all over the world, especially in sub-Saharan Africa. CD209 and CD28 genes act as co-stimulators and regulators of the immune system, while the STAT6 gene has been reported to mediate cytokine-induced responses. Single nucleotide polymorphisms of these genes might lead to differential disease susceptibility among populations at risk for malaria, due to alterations in the immune response. We aim to identify key drivers of the immune response to malaria infection among the three SNPs: CD209 (rs4804803), CD28 (rs35593994) and STAT6 (rs3024974). After approval and informed consent, we genotyped blood samples from a total of 531 children recruited from Nigeria using the Taqman SNP genotyping assay and performed comparative analysis of clinical covariates among malaria-infected children. Our results reveal the CD209 (rs4804803) polymorphism as a susceptibility factor for malaria infection, significantly increasing the risk of disease among children, but not CD28 (rs35593994) or STAT6 (rs3024974) polymorphisms. Specifically, individuals with the homozygous mutant allele (rs4804803G/G) for the CD209 gene have a significantly greater susceptibility to malaria, and presented with higher mean parasitemia. This observation may be due to a defective antigen presentation and priming, leading to an ineffective downstream adaptive immune response needed to combat infection, as well as the resultant higher parasitemia and disease manifestation. We conclude that the CD209 gene is a critical driver of the immune response during malaria infection, and can serve as a predictor of disease susceptibility or a biomarker for disease diagnosis.

12.
Afr Health Sci ; 20(3): 1035-1044, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33402949

RESUMEN

BACKGROUND: Iron deficiency is a dominant source of anaemia in many settings. To evaluate the key cause of anaemia in the study area, the prevalence of anaemia due to major public health diseases was compared with anaemia due to iron deficiency. METHODS: Pregnant women were recruited from ante-natal (n=490) and HIV clinics (n=217) with their personal data documented using a questionnaire. Microscopy of Giemsa-stained thick smears was used for detection of malaria parasites while helminths in stools were detected using direct smear method. Haematocrit values were determined by capillary method. Serum ferritin levels were determined using enzyme-linked immunosorbent assay. Data was analysed using SPSS version 22.0. RESULTS: The mean age of the recruited women was 28.6±5.4 years old. There were 68.1% cases of anaemia of which 35.5% was due to infections only predominantly HIV and malaria, 14.9% from unknown sources while anaemia due to iron deficiency only was 7.1%. CONCLUSION: It can safely be inferred that malaria and HIV predispose to anaemia than iron deficiency in the study area. Although pregnant women are dewormed and given IPTp for helminths and malaria treatment respectively, there should be complementary routine malaria screening at ANC visits for those with HCT values <33% and those infected with HIV.


Asunto(s)
Anemia Ferropénica/epidemiología , Anemia/epidemiología , Anemia/parasitología , Ferritinas/sangre , Helmintiasis/epidemiología , Malaria/epidemiología , Complicaciones Hematológicas del Embarazo/epidemiología , Complicaciones Parasitarias del Embarazo/epidemiología , Adulto , Animales , Estudios Transversales , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Helmintos/aislamiento & purificación , Humanos , Nigeria/epidemiología , Embarazo , Complicaciones Hematológicas del Embarazo/sangre , Mujeres Embarazadas , Atención Prenatal , Factores Socioeconómicos
13.
Acta Trop ; 196: 121-125, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31103699

RESUMEN

Prompt diagnosis and appropriate treatment of malaria remain the hallmark for reducing malaria-related mortality in high transmission areas. Plasmodium falciparum histidine-rich protein2 (PfHRP2) based rapid diagnostic tests (RDT) play a vital role in prompt and accurate malaria diagnosis. However, pfhrp2 gene deletion threatens the RDT test sensitivity. This study reports the presence of pfhrp2 and pfhrp3 genes deletion among parasite isolates in Nigeria. Febrile children were screened using histidine-rich protein (HRP2) specific RDT (SD-Bioline RDT) and microscopy for P. falciparum infections. All RDT negative samples were re-evaluated by polymerase chain reaction (PCR). The presence of parasite in RDT false negative cases and randomly selected RDT positive cases were validated using PCRs targeting glutamate-rich protein (glurp) and merozoite surface proteins (msp-1 and msp-2). Thereafter, exon 2 of pfhrp2 and pfhrp3 were amplified, and Sanger sequenced. A total of 511 febrile children were enrolled out of which 309 (61%) were positive by RDT. The presence of pfhrp2 and pfhrp3 genes were analyzed in 66 PCR positive samples comprising of 31 RDT false negative and 35 RDT true positive randomly selected samples. The pfhrp2 and pfhrp3 genes failed to amplify in 17% (11/66) and 6% (4/66) samples, respectively. Seven of the eleven samples had only pfhrp2 deletion while four had both pfhrp2 and pfhrp3 deletions. The absence of the pfhrp2 gene may be responsible for the seven RDT false negative cases observed. Three RDT positive cases lacked pfhrp2 whereas pfhrp3 was absent in only four RDT false negative cases. The pfhrp2 and pfhrp3 amino acid repeat sequences were highly diverse. The P. falciparum isolates lacking pfhrp2 and pfhrp3 genes may be circulating and contributing to RDT false negativity in Nigeria. More studies in larger population and seasonally defined cases will be needed to determine the extent of pfhrp2/3 genes deletion in different geographical areas of Nigeria.


Asunto(s)
Antígenos de Protozoos/genética , Pruebas Diagnósticas de Rutina/métodos , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Preescolar , Eliminación de Gen , Humanos , Malaria Falciparum/epidemiología , Nigeria/epidemiología , Reacción en Cadena de la Polimerasa
14.
Malar J ; 17(1): 1, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29291736

RESUMEN

BACKGROUND: Nigeria carries a high burden of malaria which makes continuous surveillance for current information on genetic diversity imperative. In this study, the merozoite surface proteins (msp-1, msp-2) and glutamate-rich protein (glurp) of Plasmodium falciparum collected from two communities representing rural and urban settings in Ibadan, southwestern Nigeria were analysed. METHODS: A total of 511 febrile children, aged 3-59 months, whose parents/guardians provided informed consent, were recruited into the study. Capillary blood was obtained for malaria rapid diagnostic test, thick blood smears for parasite count and blood spots on filter paper for molecular analysis. RESULTS: Three-hundred and nine samples were successfully genotyped for msp-1, msp-2 and glurp genes. The allelic distribution of the three genes was not significantly different in the rural and urban communities. R033 and 3D7 were the most prevalent alleles in both rural and urban communities for msp-1 and msp-2, respectively. Eleven of glurp RII region genotypes, coded I-XII, with sizes ranging from 500 to 1100 base pairs were detected in the rural setting. Genotype XI (1000-1050 bp) had the highest prevalence of 41.5 and 38.5% in rural and urban settings, respectively. Overall, 82.1 and 70.0% of samples had multiclonal infection with msp-1 gene resulting in a mean multiplicity of infection (MOI) of 2.8 and 2.6 for rural and urban samples, respectively. Msp-1 and msp-2 genes displayed higher levels of diversity and higher MOI rates than the glurp gene. CONCLUSION: Significant genetic diversity was observed between rural and urban parasite populations in Ibadan, southwestern Nigeria. The results of this study show that malaria transmission intensity in these regions is still high. No significant difference was observed between rural and urban settings, except for a completely different msp-1 allele, compared to previous reports, thereby confirming the changing face of malaria transmission in these communities. This study provides important baseline information required for monitoring the impact of malaria elimination efforts in this region and data points useful in revising current protocols.


Asunto(s)
Antígenos de Protozoos/genética , Frecuencia de los Genes , Variación Genética , Malaria Falciparum/parasitología , Proteína 1 de Superficie de Merozoito/genética , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Preescolar , Estudios Transversales , Femenino , Genotipo , Técnicas de Genotipaje , Humanos , Lactante , Malaria Falciparum/epidemiología , Masculino , Epidemiología Molecular , Nigeria/epidemiología , Plasmodium falciparum/aislamiento & purificación , Prevalencia , Población Rural , Población Urbana
15.
Pathog Glob Health ; 112(2): 86-92, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29318942

RESUMEN

This study assesses the prevalence of asymptomatic Plasmodium falciparum parasitemia positivity and P. falciparum dihydrofolate reductase (pfdhfr) mutations in parasite isolates among pregnant women in Southwest Nigeria. Plasmodium falciparum parasitemia was confirmed by microscopy and nested PCR in 200 pregnant women attending antenatal care. The prevalence of pfdhfr polymorphisms was determined by direct sequencing of the gene fragments containing the C50R, N51I, C59R, S108N, and I164L mutations. Information on the use of antimalarial drugs and methods applied to prevent malaria were obtained by a questionnaire. The prevalence of asymptomatic P. falciparum infection was 30% (60/200). The frequency of the pfdhfr triple-mutant alleles (N51I, C59R, and S108N) was 63% (38/60); none of the isolates carried the I164L mutation. Among the investigated pregnant women, 40% used un-prescribed antimalarials such as dihydroartemisinin (18%), chloroquine (14%) or pyrimethamine (9%), while only 20.5% used sulfadoxine-pyrimethamine for prevention and 39.5% did not use any drug. The prevalence of P. falciparum parasitemia (37%) was higher among pregnant women who had not taken any antimalarial drugs. A significant difference in the prevalence of the pfdhfr triple-mutant alleles was observed among women who took SP (90%) compared to those who did not take any drug (82%) and women who took dihydroartemisinin (67%) p = 0.007). Poor adherence to the World Health Organisation (WHO) strategies for malaria prevention among pregnant women was observed in addition to high prevalence of pfdhfr mutations. These findings underline the need to improve control of malaria among pregnant women in the study area.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria Falciparum/parasitología , Mutación Missense , Plasmodium falciparum/enzimología , Complicaciones Infecciosas del Embarazo/parasitología , Pirimetamina/uso terapéutico , Sulfadoxina/uso terapéutico , Tetrahidrofolato Deshidrogenasa/genética , Adolescente , Adulto , Animales , Enfermedades Asintomáticas/epidemiología , Estudios Transversales , Combinación de Medicamentos , Femenino , Humanos , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Microscopía , Nigeria/epidemiología , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Prevalencia , Análisis de Secuencia de ADN , Adulto Joven
16.
Immunogenetics ; 70(2): 135-140, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28963676

RESUMEN

Susceptibility to malaria infection has been associated with host genetic polymorphisms that differs between groups. We hypothesize that Toll-interacting proteins (TOLLIP), vitamin D receptor (VDR) and tumor necrosis factor-α (TNF) genes are significant contributors to susceptibility and disease severity in Plasmodium falciparum (Pf) infection. Our aim is to explore the genomic diversity and haplotype frequency of these genes, as well as extrapolate possible association with markers of severity, between malaria-infected and healthy controls. Genomic DNA samples extracted from the blood of 107 malaria-infected patients and 190 uninfected controls were analyzed, with no difference in genotypic or allelic frequencies of TOLLIP and VDR polymorphisms. However, a significant difference in the genotypic (p = 2.20E-16) and allelic frequencies (p = 2.20E-16) of the TNF-α (snp rs1800629) polymorphism was found. The preponderance of the mutant variant among the malaria-infected show a possible impaired capacity to mount an effective immune response, potentially confirmed by our association results. This result calls for analysis of clearly delineated uncomplicated versus severe disease groups, including serum assays, providing a basis to conclude that susceptibility to malaria infection and potential contribution to disease severity is significantly associated with polymorphisms of the tumor necrosis factor-α but not TOLLIP or VDR genes.


Asunto(s)
Malaria Falciparum/genética , Factor de Necrosis Tumoral alfa/genética , Adulto , África del Sur del Sahara/epidemiología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Haplotipos , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Malaria/genética , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Receptores de Calcitriol/genética
17.
Infect Dis (Auckl) ; 10: 1178633617726781, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28970738

RESUMEN

CD14 is a multifunctional receptor expressed on many cell types and has been shown to mediate immune response resulting in the activation of an inflammatory cascade, with polymorphism of its promoter (rs2569190) found to be associated with susceptibility to several diseases. In malaria infection, the CD14 gene demonstrated a pathogenic profile in regulating experimental cerebral malaria, with reports of elevated levels of soluble CD14 in serum of patients but no definitive conclusion. We present a detailed analysis of genetic diversity of CD14 promoter gene (snp -159 C/T; rs2519190) polymorphism between a malaria-infected group and uninfected controls and its association with clinical parameters of disease. Genomic DNA samples obtained from 106 Plasmodium falciparum malaria-infected patients and 277 uninfected controls were elucidated with a polymerase chain reaction-restriction fragment length polymorphism (RFLP) assay. Our results show a significant diversity (P = 3.32E-06) in the genotypic frequency (3.8% versus 22.4%) of the rs2569190 mutant variant between the malaria-infected group and controls, respectively. The mutant allele had the lowest frequency among the malaria-infected group demonstrating its necessity for infection. Mean parasitemia (parasites/µL of blood) was significantly regulated based on CD14 polymorphic profile (19 855 versus 37 041 versus 49 396 for homozygote mutants, heterozygotes, and homozygote wild type, respectively). Interestingly, we found no association between CD14 genetic variants with fever, age of patients, or anemia. How this affects disease severity between subregional and continental groups deserves further clarification, including extending these studies in a larger group and among severe and asymptomatic patients with malaria.

18.
Clin Infect Dis ; 63(suppl 5): S245-S255, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27941101

RESUMEN

BACKGROUND: Malaria-endemic countries are encouraged to increase, expedite, and standardize care based on parasite diagnosis and treat confirmed malaria using oral artemisinin-based combination therapy (ACT) or rectal artesunate plus referral when patients are unable to take oral medication. METHODS: In 172 villages in 3 African countries, trained community health workers (CHWs) assessed and diagnosed children aged between 6 months and 6 years using rapid histidine-rich protein 2 (HRP2)-based diagnostic tests (RDTs). Patients coming for care who could take oral medication were treated with ACTs, and those who could not were treated with rectal artesunate and referred to hospital. The full combined intervention package lasted 12 months. Changes in access and speed of care and clinical course were determined through 1746 random household interviews before and 3199 during the intervention. RESULTS: A total of 15 932 children were assessed: 6394 in Burkina Faso, 2148 in Nigeria, and 7390 in Uganda. Most children assessed (97.3% [15 495/15 932]) were febrile and most febrile cases (82.1% [12 725/15 495]) tested were RDT positive. Almost half of afebrile episodes (47.6% [204/429]) were RDT positive. Children eligible for rectal artesunate contributed 1.1% of episodes. The odds of using CHWs as the first point of care doubled (odds ratio [OR], 2.15; 95% confidence interval [CI], 1.9-2.4; P < .0001). RDT use changed from 3.2% to 72.9% (OR, 80.8; 95% CI, 51.2-127.3; P < .0001). The mean duration of uncomplicated episodes reduced from 3.69 ± 2.06 days to 3.47 ± 1.61 days, Degrees of freedom (df) = 2960, Student's t (t) = 3.2 (P = .0014), and mean duration of severe episodes reduced from 4.24 ± 2.26 days to 3.7 ± 1.57 days, df = 749, t = 3.8, P = .0001. There was a reduction in children with danger signs from 24.7% before to 18.1% during the intervention (OR, 0.68; 95% CI, .59-.78; P < .0001). CONCLUSIONS: Provision of diagnosis and treatment via trained CHWs increases access to diagnosis and treatment, shortens clinical episode duration, and reduces the number of severe cases. This approach, recommended by the World Health Organization, improves malaria case management. CLINICAL TRIALS REGISTRATION: ISRCTN13858170.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/epidemiología , Administración Oral , Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Artemisininas/metabolismo , Artemisininas/uso terapéutico , Artesunato , Burkina Faso/epidemiología , Niño , Preescolar , Agentes Comunitarios de Salud , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Lactante , Malaria/tratamiento farmacológico , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Masculino , Nigeria/epidemiología , Proteínas/metabolismo , Derivación y Consulta , Uganda/epidemiología
19.
Clin Infect Dis ; 63(suppl 5): S256-S263, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27941102

RESUMEN

BACKGROUND: Community health workers (CHWs) were trained in Burkina Faso, Nigeria, and Uganda to diagnose febrile children using malaria rapid diagnostic tests, and treat positive malaria cases with artemisinin-based combination therapy (ACT) and those who could not take oral medicines with rectal artesunate. We quantified the impact of this intervention on private household costs for childhood febrile illness. METHODS: Households with recent febrile illness in a young child in previous 2 weeks were selected randomly before and during the intervention and data obtained on household costs for the illness episode. Household costs included consultation fees, registration costs, user fees, diagnosis, bed, drugs, food, and transport costs. Private household costs per episode before and during the intervention were compared. The intervention's impact on household costs per episode was calculated and projected to districtwide impacts on household costs. RESULTS: Use of CHWs increased from 35% of illness episodes before the intervention to 50% during the intervention (P < .0001), and total household costs per episode decreased significantly in each country: from US Dollars (USD) $4.36 to USD $1.54 in Burkina Faso, from USD $3.90 to USD $2.04 in Nigeria, and from USD $4.46 to USD $1.42 in Uganda (all P < .0001). There was no difference in the time used by the child's caregiver to care for a sick child (59% before intervention vs 51% during intervention spent ≤2 days). Using the most recent population figures for each study district, we estimate that the intervention could save households a total of USD $29 965, USD $254 268, and USD $303 467, respectively, in the study districts in Burkina Faso, Nigeria, and Uganda. CONCLUSIONS: Improving access to malaria diagnostics and treatments in malaria-endemic areas substantially reduces private household costs. The key challenge is to develop and strengthen community human resources to deliver the intervention, and ensure adequate supplies of commodities and supervision. We demonstrate feasibility and benefit to populations living in difficult circumstances. CLINICAL TRIALS REGISTRATION: ISRCTN13858170.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/diagnóstico , Malaria/tratamiento farmacológico , Adolescente , Adulto , Antimaláricos/economía , Artemisininas/economía , Artemisininas/uso terapéutico , Artesunato , Burkina Faso/epidemiología , Preescolar , Agentes Comunitarios de Salud/estadística & datos numéricos , Composición Familiar , Femenino , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Malaria/epidemiología , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Encuestas y Cuestionarios , Uganda/epidemiología , Adulto Joven
20.
Clin Infect Dis ; 63(suppl 5): S264-S269, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27941103

RESUMEN

BACKGROUND: Use of community health workers (CHWs) to increase access to diagnosis and treatment of malaria is recommended by the World Health Organization. The present article reports on training and performance of CHWs in applying these recommendations. METHODS: Two hundred seventy-nine CHWs were trained for 3-5 days in Burkina Faso, Nigeria, and Uganda, and 19 were certified to diagnose and treat only uncomplicated malaria and 235 to diagnose and treat both uncomplicated and severe malaria. Almost 1 year after training, 220 CHWs were assessed using standard checklists using facility staff responses as the reference standard. RESULTS: Training models were slightly different in the 3 countries, but the same topics were covered. The main challenges noticed were the low level of education in rural areas and the involvement of health staff in the supervision process. Overall performance was 98% (with 99% in taking history, 95% in measuring temperature, 85% for measuring respiratory rates, 98% for diagnosis, 98% for classification, and 99% for prescribing treatment). Young, single, new CHWs performed better than their older, married, more experienced counterparts. CONCLUSIONS: Training CHWs for community-based diagnosis and treatment of uncomplicated and severe malaria is possible with basic and refresher training and close supervision of CHWs' performance. CLINICAL TRIALS REGISTRATION: ISRCTRS13858170.


Asunto(s)
Antimaláricos/uso terapéutico , Agentes Comunitarios de Salud/estadística & datos numéricos , Malaria/tratamiento farmacológico , Administración Rectal , Adulto , África del Sur del Sahara/epidemiología , Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Artemisininas/uso terapéutico , Artesunato , Burkina Faso/epidemiología , Femenino , Humanos , Malaria/epidemiología , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Población Rural , Uganda/epidemiología
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