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1.
Front Oncol ; 14: 1356654, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476363

RESUMO

Objective: To explore the experiences of Malawian women who underwent a human papillomavirus (HPV)-based screen-triage-treat algorithm for cervical cancer (CxCa) prevention. This algorithm included GeneXpert® HPV testing of self-collected vaginal samples, visual inspection with acetic acid (VIA) and colposcopy for HPV-positive women, and thermal ablation of ablation-eligible women. Method: In-depth interviews were conducted with participants of a trial that evaluated the feasibility of a HPV-based screen-triage-treat algorithm among women living with HIV and HIV negative women in Lilongwe, Malawi. Participants were recruited from 3 groups: 1) HPV-negative; 2) HPV-positive/VIA-negative; 3) HPV-positive/VIA-positive and received thermal ablation. Interviews explored baseline knowledge of CxCa and screening, attitudes towards self-collection, and understanding of test results. Content analysis was conducted using NVIVO v12. Results: Thematic saturation was reached at 25 interviews. Advantages of HPV self-collection to participants were convenience of sampling, same-day HPV results and availability of same-day treatment. There was confusion surrounding HPV-positive/VIA-negative results, as some participants still felt treatment was needed. Counseling, and in particular anticipatory guidance, was key in helping participants understand complex screening procedures and results. Overall, participants expressed confidence in the HPV screen-triage-treat strategy. Discussion: HPV testing through self-collected samples is a promising tool to increase CxCa screening coverage. A multi-step screening algorithm utilizing HPV self-testing, VIA triage and thermal ablation treatment requires proper counseling and anticipatory guidance to improve patient understanding. Incorporating thorough counseling in CxCa screening programs can change women's perspectives about screening, build trust in healthcare systems, and influence healthcare seeking behavior towards routine screening and prevention.

2.
Lancet ; 403(10424): 365-378, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38224710

RESUMO

BACKGROUND: The efficacy of daily co-trimoxazole, an antifolate used for malaria chemoprevention in pregnant women living with HIV, is threatened by cross-resistance of Plasmodium falciparum to the antifolate sulfadoxine-pyrimethamine. We assessed whether addition of monthly dihydroartemisinin-piperaquine to daily co-trimoxazole is more effective at preventing malaria infection than monthly placebo plus daily co-trimoxazole in pregnant women living with HIV. METHODS: We did an individually randomised, two-arm, placebo-controlled trial in areas with high-grade sulfadoxine-pyrimethamine resistance in Kenya and Malawi. Pregnant women living with HIV on dolutegravir-based combination antiretroviral therapy (cART) who had singleton pregnancies between 16 weeks' and 28 weeks' gestation were randomly assigned (1:1) by computer-generated block randomisation, stratified by site and HIV status (known positive vs newly diagnosed), to daily co-trimoxazole plus monthly dihydroartemisinin-piperaquine (three tablets of 40 mg dihydroartemisinin and 320 mg piperaquine given daily for 3 days) or daily co-trimoxazole plus monthly placebo. Daily co-trimoxazole consisted of one tablet of 160 mg sulfamethoxazole and 800 mg trimethoprim. The primary endpoint was the incidence of Plasmodium infection detected in the peripheral (maternal) or placental (maternal) blood or tissue by PCR, microscopy, rapid diagnostic test, or placental histology (active infection) from 2 weeks after the first dose of dihydroartemisinin-piperaquine or placebo to delivery. Log-binomial regression was used for binary outcomes, and Poisson regression for count outcomes. The primary analysis was by modified intention to treat, consisting of all randomised eligible participants with primary endpoint data. The safety analysis included all women who received at least one dose of study drug. All investigators, laboratory staff, data analysts, and participants were masked to treatment assignment. This trial is registered with ClinicalTrials.gov, NCT04158713. FINDINGS: From Nov 11, 2019, to Aug 3, 2021, 904 women were enrolled and randomly assigned to co-trimoxazole plus dihydroartemisinin-piperaquine (n=448) or co-trimoxazole plus placebo (n=456), of whom 895 (99%) contributed to the primary analysis (co-trimoxazole plus dihydroartemisinin-piperaquine, n=443; co-trimoxazole plus placebo, n=452). The cumulative risk of any malaria infection during pregnancy or delivery was lower in the co-trimoxazole plus dihydroartemisinin-piperaquine group than in the co-trimoxazole plus placebo group (31 [7%] of 443 women vs 70 [15%] of 452 women, risk ratio 0·45, 95% CI 0·30-0·67; p=0·0001). The incidence of any malaria infection during pregnancy or delivery was 25·4 per 100 person-years in the co-trimoxazole plus dihydroartemisinin-piperaquine group versus 77·3 per 100 person-years in the co-trimoxazole plus placebo group (incidence rate ratio 0·32, 95% CI 0·22-0·47, p<0·0001). The number needed to treat to avert one malaria infection per pregnancy was 7 (95% CI 5-10). The incidence of serious adverse events was similar between groups in mothers (17·7 per 100 person-years in the co-trimoxazole plus dihydroartemisinin-piperaquine group [23 events] vs 17·8 per 100 person-years in the co-trimoxazole group [25 events]) and infants (45·4 per 100 person-years [23 events] vs 40·2 per 100 person-years [21 events]). Nausea within the first 4 days after the start of treatment was reported by 29 (7%) of 446 women in the co-trimoxazole plus dihydroartemisinin-piperaquine group versus 12 (3%) of 445 women in the co-trimoxazole plus placebo group. The risk of adverse pregnancy outcomes did not differ between groups. INTERPRETATION: Addition of monthly intermittent preventive treatment with dihydroartemisinin-piperaquine to the standard of care with daily unsupervised co-trimoxazole in areas of high antifolate resistance substantially improves malaria chemoprevention in pregnant women living with HIV on dolutegravir-based cART and should be considered for policy. FUNDING: European and Developing Countries Clinical Trials Partnership 2; UK Joint Global Health Trials Scheme (UK Foreign, Commonwealth and Development Office; Medical Research Council; National Institute for Health Research; Wellcome); and Swedish International Development Cooperation Agency.


Assuntos
Antimaláricos , Artemisininas , Antagonistas do Ácido Fólico , Infecções por HIV , Malária , Piperazinas , Quinolinas , Feminino , Humanos , Lactente , Gravidez , Antimaláricos/efeitos adversos , Quimioprevenção , Antagonistas do Ácido Fólico/uso terapêutico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Quênia/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Malaui/epidemiologia , Placenta , Resultado da Gravidez , Gestantes , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Método Duplo-Cego
3.
BMC Health Serv Res ; 22(1): 1196, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151553

RESUMO

BACKGROUND: Community health workers (CHWs) are essential field-based personnel and increasingly used to deliver priority interventions to achieve universal health coverage. Existing literature allude to the potential for detrimental effects of multi-tasking CHWs. This study objective was to assess the impact of integrating cervical cancer screening and prevention therapy (CCSPT) with family planning (FP) on time utilization among CHWs. METHODS: A time and motion study was conducted in 7 health facilities in Malawi. Data was collected at baseline between October-July 2019, and 12 months after CCSPT implementation between July and August 2021. CHWs trained to deliver CCSPT were continuously observed in real time while their activities were timed by independent observers. We used paired sample t-test to assess pre-post differences in average hours CHWs spent on the following key activities, before and after CCSPT implementation: clinical and preventive care; administration; FP; and non-work-related tasks. Regression models were used to ascertain impact of CCSPT on average durations CHWs spent on key activities. RESULTS: Thirty-seven (n = 37) CHWs were observed. Their mean age and years of experience were 42 and 17, respectively. Overall, CHWs were observed for 323 hours (inter quartile range: 2.8-5.5). Compared with the period before CCSPT, the proportion of hours CHWs spent on clinical and preventive care, administration and non-work-related activities were reduced by 13.7, 8.7 and 34.6%, respectively. CHWs spent 75% more time on FP services after CCSPT integration relative to the period before CCSPT. The provision of CCSPT resulted in less time that CHWs devoted towards clinical and preventive care but this reduction was not significant. Following CCPST, CHWs spent significantly few hours on non-work-related activities. CONCLUSION: Introduction of CCSPT was not very detrimental to pre-existing community services. CHWs managed their time ensuring additional efforts required for CCSPT were not at the expense of essential activities. The programming and policy implications are that multi-tasking CHWs with CCSPT will not have substantial opportunity costs.


Assuntos
Agentes Comunitários de Saúde , Neoplasias do Colo do Útero , Detecção Precoce de Câncer , Feminino , Humanos , Malaui , Estudos de Tempo e Movimento , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle
4.
Contemp Clin Trials Commun ; 26: 100903, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35243124

RESUMO

Cervical cancer is the leading cause of cancer mortality among Malawian women, despite being preventable through screening and preventive therapy. In 2004, Malawi implemented a national screening program, using visual inspection with acetic acid (VIA) and cryotherapy, but its success has been limited due to equipment and human resources challenges. Since the development of that program, new technologies for screening and treatment that are less resource-intensive and more scalable have become available. GeneXpert systems provide fast, accurate HPV results and are increasingly available in low-income countries. Self-collection for human papillomavirus (HPV) testing is a validated method for screening and improves uptake. Thermal ablation provides an alternative ablative treatment that is simpler to use than cryotherapy and can be performed with portable devices. Meanwhile, urine HPV testing methods provide promising options for primary screening. We designed a single-arm prospective study to investigate a novel HPV screen-triage-treat strategy among 1250 women in Lilongwe, Malawi. Our proposed strategy consists of (1) Xpert HPV testing of self-collected samples, (2) VIA and colposcopy for HPV-positive women, and (3) thermal ablation for HPV-positive/ablation-eligible women. We will collect cervical biopsies, Pap smears, and endocervical samples to validate the HPV results and VIA/colposcopy findings against endpoints of high-grade cervical intraepithelial neoplasia or cancer (CIN2+). We will evaluate same-day completion of our algorithm, its performance in triaging women for treatment, and 24-week treatment efficacy of thermal ablation. We will also explore the performance of HPV and methylation tests in urine samples, as compared to provider- and self-collected cervicovaginal samples.

5.
Pilot Feasibility Stud ; 7(1): 98, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879259

RESUMO

BACKGROUND: Cervical cancer is the leading cause of cancer incidence and mortality among Malawian women, despite being a largely preventable disease. Implementing a cervical cancer screening and preventive treatment (CCSPT) program that utilizes rapid human papillomavirus (HPV) testing on self-collected cervicovaginal samples for screening and thermal ablation for treatment may achieve greater coverage than current programs that use visual inspection with acetic acid (VIA) for screening and cryotherapy for treatment. Furthermore, self-sampling creates the opportunity for community-based screening to increase uptake in populations with low screening rates. Malawi's public health system utilizes regularly scheduled outreach and village-based clinics to provide routine health services like family planning. Cancer screening is not yet included in these community services. Incorporating self-sampled HPV testing into national policy could address cervical cancer screening barriers in Malawi, though at present the effectiveness, acceptability, appropriateness, feasibility, and cost-effectiveness still need to be demonstrated. METHODS: We designed a cluster randomized feasibility trial to determine the effectiveness, acceptability, appropriateness, feasibility, and budget impact of two models for integrating a HPV-based CCSPT program into family planning (FP) services in Malawi: model 1 involves only clinic-based self-sampled HPV testing, whereas model 2 includes both clinic-based and community-based self-sampled HPV testing. Our algorithm involves self-collection of samples for HPV GeneXpert® testing, visual inspection with acetic acid for HPV-positive women to determine ablative treatment eligibility, and same-day thermal ablation for treatment-eligible women. Interventions will be implemented at 14 selected facilities. Our primary outcome will be the uptake of cervical cancer screening and family planning services during the 18 months of implementation, which will be measured through an Endline Household Survey. We will also conduct mixed methods assessments to understand the acceptability, appropriateness, and feasibility of the interventions, and a cost analysis to assess budget impact. DISCUSSION: Our trial will provide in-depth information on the implementation of clinic-only and clinic-and-community models for integrating self-sampled HPV testing CCSPT with FP services in Malawi. Findings will provide valuable insight for policymakers and implementers in Malawi and other resource-limited settings with high cervical cancer burden. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04286243 . Registered on February 26, 2020.

6.
Nat Commun ; 11(1): 3799, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732892

RESUMO

Plasmodium falciparum in pregnancy is a major cause of adverse pregnancy outcomes. We combine performance estimates of standard rapid diagnostic tests (RDT) from trials of intermittent screening and treatment in pregnancy (ISTp) with modelling to assess whether screening at antenatal visits improves upon current intermittent preventative therapy with sulphadoxine-pyrimethamine (IPTp-SP). We estimate that RDTs in primigravidae at first antenatal visit are substantially more sensitive than in non-pregnant adults (OR = 17.2, 95% Cr.I. 13.8-21.6), and that sensitivity declines in subsequent visits and with gravidity, likely driven by declining susceptibility to placental infection. Monthly ISTp with standard RDTs, even with highly effective drugs, is not superior to monthly IPTp-SP. However, a hybrid strategy, recently adopted in Tanzania, combining testing and treatment at first visit with IPTp-SP may offer benefit, especially in areas with high-grade SP resistance. Screening and treatment in the first trimester, when IPTp-SP is contraindicated, could substantially improve pregnancy outcomes.


Assuntos
Malária Falciparum/diagnóstico , Malária Falciparum/prevenção & controle , Programas de Rastreamento/métodos , Complicações Parasitárias na Gravidez/prevenção & controle , Cuidado Pré-Natal/métodos , Antimaláricos/uso terapêutico , Combinação de Medicamentos , Feminino , Política de Saúde , Humanos , Malária Falciparum/tratamento farmacológico , Testes de Sensibilidade Parasitária , Plasmodium falciparum/efeitos dos fármacos , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Primeiro Trimestre da Gravidez , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Tanzânia , Organização Mundial da Saúde
7.
Malar J ; 19(1): 119, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32197619

RESUMO

BACKGROUND: Drug safety assessments in clinical trials present unique analytical challenges. Some of these include adjusting for individual follow-up time, repeated measurements of multiple outcomes and missing data among others. Furthermore, pre-specifying appropriate analysis becomes difficult as some safety endpoints are unexpected. Although existing guidelines such as CONSORT encourage thorough reporting of adverse events (AEs) in clinical trials, they provide limited details for safety data analysis. The limited guidelines may influence suboptimal analysis by failing to account for some analysis challenges above. A typical example where such challenges exist are trials of anti-malarial drugs for malaria prevention during pregnancy. Lack of proper standardized evaluation of the safety of antimalarial drugs has limited the ability to draw conclusions about safety. Therefore, a systematic review was conducted to establish the current practice in statistical analysis for preventive antimalarial drug safety in pregnancy. METHODS: The search included five databases (PubMed, Embase, Scopus, Malaria in Pregnancy Library and Cochrane Central Register of Controlled Trials) to identify original English articles reporting Phase III randomized controlled trials (RCTs) on anti-malarial drugs for malaria prevention in pregnancy published from January 2010 to July 2019. RESULTS: Eighteen trials were included in this review that collected multiple longitudinal safety outcomes including AEs. Statistical analysis and reporting of the safety outcomes in all the trials used descriptive statistics; proportions/counts (n = 18, 100%) and mean/median (n = 2, 11.1%). Results presentation included tabular (n = 16, 88.9%) and text description (n = 2, 11.1%). Univariate inferential methods were reported in most trials (n = 16, 88.9%); including Chi square/Fisher's exact test (n = 12, 66.7%), t test (n = 2, 11.1%) and Mann-Whitney/Wilcoxon test (n = 1, 5.6%). Multivariable methods, including Poisson and negative binomial were reported in few trials (n = 3, 16.7%). Assessment of a potential link between missing efficacy data and safety outcomes was not reported in any of the trials that reported efficacy missing data (n = 7, 38.9%). CONCLUSION: The review demonstrated that statistical analysis of safety data in anti-malarial drugs for malarial chemoprevention in pregnancy RCTs is inadequate. The analyses insufficiently account for multiple safety outcomes potential dependence, follow-up time and informative missing data which can compromise anti-malarial drug safety evidence development, based on the available data.


Assuntos
Antimaláricos/administração & dosagem , Quimioprevenção/estatística & dados numéricos , Malária/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Adulto , Antimaláricos/efeitos adversos , Quimioprevenção/métodos , Interpretação Estatística de Dados , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/parasitologia , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Sex Transm Dis ; 47(4): 275-279, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32168286

RESUMO

BACKGROUND: Human papilloma virus (HPV), the causative agent for cervical cancer, can be tested for using self-collected vaginal samples. Self-collection is promising for HPV screening in hard-to-reach populations. To assess the relationship between willingness to self-collect and subsequent uptake of self-collection, we conducted a longitudinal study of reproductive-age women in rural Malawi. METHODS: At baseline, we asked women if they would be willing to self-collect a vaginal sample for HPV testing. At follow-up (12-18 months later), we offered the same women the opportunity to self-collect a sample for HPV testing. We examined unadjusted and adjusted associations between baseline willingness to self-collect a sample for HPV testing and uptake of self-collection at follow-up using log-binomial models. RESULTS: Among 122 women who, at baseline, indicated willingness to self-collect, n = 65 (53%) agreed to self-collect a sample at follow-up. Of 64 women who stated unwillingness at baseline to self-collect, n = 30 (47%) self-collected a sample for testing at follow-up. We observed no association between women's willingness at baseline and their observed self-collection decision at follow-up (unadjusted prevalence ratio, 1.14; 95% confidence interval, 0.83-1.55). The association remained null after adjustment for age, awareness of cervical cancer, and perceived behavioral control. CONCLUSIONS: Our results suggest that evaluation of acceptability of self-collection should go beyond simply asking women if they would be willing to self-collect a vaginal sample. Given that half of this study's participants agreed to self-collect a sample when the opportunity was offered, regardless of their previously stated preferences, self-collection should be offered to everyone.


Assuntos
Intenção , Programas de Rastreamento/métodos , Papillomaviridae , Infecções por Papillomavirus , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adulto , Feminino , Humanos , Estudos Longitudinais , Malaui/epidemiologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/prevenção & controle , Vigilância da População , População Rural , Autocuidado , Manejo de Espécimes , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle
9.
PLoS Med ; 16(10): e1002914, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31574087

RESUMO

BACKGROUND: Malaria in pregnancy is associated with adverse birth outcomes. However, the underlying mechanisms remain poorly understood. Tight regulation of angiogenic, metabolic, and inflammatory pathways are essential for healthy pregnancies. We hypothesized that malaria disrupts these pathways leading to preterm birth (PTB). METHODS AND FINDINGS: We conducted a secondary analysis of a randomized trial of malaria prevention in pregnancy conducted in Malawi from July 21, 2011, to March 18, 2013. We longitudinally assessed circulating mediators of angiogenic, metabolic, and inflammatory pathways during pregnancy in a cohort of HIV-negative women (n = 1,628), with a median age of 21 years [18, 25], and 562 (35%) were primigravid. Pregnancies were ultrasound dated, and samples were analyzed at 13 to 23 weeks (Visit 1), 28 to 33 weeks (Visit 2), and/or 34 to 36 weeks (Visit 3). Malaria prevalence was high; 70% (n = 1,138) had PCR-positive Plasmodium falciparum infection at least once over the course of pregnancy and/or positive placental histology. The risk of delivering preterm in the entire cohort was 20% (n = 304/1506). Women with malaria before 24 weeks gestation had a higher risk of PTB (24% versus 18%, p = 0.005; adjusted relative risk [aRR] 1.30, 95% confidence interval [CI] 1.04-1.63, p = 0.021); and those who were malaria positive only before week 24 had an even greater risk of PTB (28% versus 17%, p = 0.02; with an aRR of 1.67, 95% CI 1.20-2.30, p = 0.002). Using linear mixed-effects modeling, malaria before 24 weeks gestation was associated with altered kinetics of inflammatory (C-Reactive Protein [CRP], Chitinase 3-like protein-1 [CHI3L1], Interleukin 18 Binding Protein [IL-18BP], soluble Tumor Necrosis Factor receptor II [sTNFRII], soluble Intercellular Adhesion Molecule-1 [sICAM-1]), angiogenic (soluble Endoglin [sEng]), and metabolic mediators (Leptin, Angiopoietin-like 3 [Angptl3]) over the course of pregnancy (χ2 > 13.0, p ≤ 0.001 for each). Limitations include being underpowered to assess the impact on nonviable births, being unable to assess women who had not received any antimalarials, and, because of the exposure to antimalarials in the second trimester, there were limited numbers of malaria infections late in pregnancy. CONCLUSIONS: Current interventions for the prevention of malaria in pregnancy are initiated at the first antenatal visit, usually in the second trimester. In this study, we found that many women are already malaria-infected by their first visit. Malaria infection before 24 weeks gestation was associated with dysregulation of essential regulators of angiogenesis, metabolism, and inflammation and an increased risk of PTB. Preventing malaria earlier in pregnancy may reduce placental dysfunction and thereby improve birth outcomes in malaria-endemic settings.


Assuntos
Malária Falciparum/complicações , Malária Falciparum/diagnóstico , Neovascularização Patológica , Complicações Infecciosas na Gravidez/diagnóstico , Nascimento Prematuro/prevenção & controle , Adulto , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Inflamação/complicações , Modelos Lineares , Malaui , Gravidez , Nascimento Prematuro/epidemiologia , Risco , Resultado do Tratamento , Ultrassonografia Pré-Natal , Adulto Jovem
10.
Glob Heart ; 14(2): 109-118, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31324364

RESUMO

Recent studies have found an increasing burden of noncommunicable diseases in sub-Saharan Africa. A compressive search of PubMed, Medline, EMBASE, and the World Health Organization Global Health Library databases was undertaken to identify studies reporting on the prevalence, risk factors, and interventions for hypertension and diabetes in Malawi. The findings from 23 included studies revealed a high burden of hypertension and diabetes in Malawi, with estimates ranging from 15.8% to 32.9% and from 2.4% to 5.6%, respectively. Associated risk factors included old age, tobacco smoking, excessive alcohol consumption, obesity, physical inactivity, high salt and sugar intake, low fruit and vegetable intake, high body mass index, and high waist-to-hip ratio. Certain antiretroviral therapy regimens were also associated with increased diabetes and hypertension risk in human immunodeficiency virus patient populations. Nationwide, the quality of clinical care was generally limited and demonstrated a need for innovative and targeted interventions to prevent, control, and treat noncommunicable diseases in Malawi.


Assuntos
Diabetes Mellitus/prevenção & controle , Hipertensão/prevenção & controle , Doenças não Transmissíveis/prevenção & controle , Diabetes Mellitus/epidemiologia , Humanos , Hipertensão/epidemiologia , Malaui/epidemiologia , Doenças não Transmissíveis/epidemiologia , Prevalência , Fatores de Risco
11.
Sci Rep ; 9(1): 7878, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133672

RESUMO

In a randomised trial comparing intermittent screening and treatment (IST) with dihydroartemisinin-piperaquine (DP) and intermittent preventive therapy against malaria in pregnancy (IPT) with sulfadoxine-pyrimethamine (SP) in Malawi, the impacts of IST-DP and IPT-SP on the development and maintenance of malaria antibody immunity were compared. Pregnant Malawian women were randomised to receive IST-DP or IPT-SP. In a nested study, paired enrolment and delivery plasma samples from 681 women were assayed for antibodies against recombinant antigens and for IgG and opsonising antibodies to antigens found on infected erythrocytes (IEs). At delivery, antibody responses did not differ between study arms. Between enrolment and delivery, antibodies to recombinant antigens decreased, whereas antibodies to IEs including opsonising antibodies remained stable. Overall, changes in antibody responses over pregnancy did not differ by treatment arm. Stratifying by gravidity, antibody to schizont extract decreased more in multigravidae receiving IST-DP than IPT-SP. There was minimal impact of treatment arm on the development and maintenance of malaria immunity. While antibodies to recombinant antigens declined between enrolment and delivery, antibodies directed against IEs tended to be more stable, suggesting longer-lasting protection.Clinical trial registration: Pa n African Clinical Trials Registry (PACTR201103000280319) 14/03/2011. URL: http://www.isrctn.com/ISRCTN69800930 .


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Complicações Parasitárias na Gravidez/tratamento farmacológico , Pirimetamina/uso terapêutico , Quinolinas/uso terapêutico , Sulfadoxina/uso terapêutico , Adolescente , Adulto , Anticorpos Antiprotozoários/imunologia , Combinação de Medicamentos , Feminino , Humanos , Malária Falciparum/diagnóstico , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Malaui/epidemiologia , Programas de Rastreamento , Plasmodium falciparum/imunologia , Plasmodium falciparum/isolamento & purificação , Gravidez , Complicações Parasitárias na Gravidez/diagnóstico , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/imunologia , Adulto Jovem
12.
J Infect Dis ; 216(3): 296-304, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28658935

RESUMO

Antenatal malaria screening with a rapid diagnostic test (RDT) and treatment only of women with positive RDT findings may potentially prevent low birth weight resulting from malaria. The consequences of subpatent antenatal infections below the detection limit of RDTs are incompletely understood. In Malawi, pregnant women of any gravidity status were tested at each antenatal visit for Plasmodium falciparum, using an RDT and polymerase chain reaction analysis, and were followed until delivery. Associations between antenatal infections and delivery outcomes were assessed with Poisson regression or analysis of variance. Compared with women with no detected antenatal P. falciparum infection, women with positive RDT findings delivered babies with a lower mean birth weight (2960 vs 2867 g; mean difference, -93 g [95% confidence interval {CI}, -27 to -159]; P = .006); this was not observed among women with only subpatent infections (mean birth weight, 3013 g; mean difference, 54 [95% CI, -33-140]; P = .2268). These differences were apparent early in pregnancy, during the second trimester: compared with uninfected women, women with positive RDT findings delivered babies with a lower mean birth weight (mean difference, -94 g [95% CI, -31 to -156]; P = .003), but women with subpatent infections did not (mean difference, 36 g [95% CI, -49-122]; P = .409). Subpatent antenatal P. falciparum infections were not associated with adverse delivery outcomes. The association of patent infections at enrollment with low birth weight suggests the importance of preventing P. falciparum infection early in pregnancy.


Assuntos
Peso ao Nascer , Malária Falciparum/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Adolescente , Adulto , Antimaláricos/uso terapêutico , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Malária Falciparum/tratamento farmacológico , Malaui , Programas de Rastreamento , Microscopia , Plasmodium falciparum , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/parasitologia , Análise de Regressão , Adulto Jovem
13.
Malar J ; 15(1): 574, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27894353

RESUMO

BACKGROUND: Malaria in pregnancy is a major cause of adverse maternal and fetal outcomes. Intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) is one of the control strategies promoted by WHO. In response to mounting resistance to SP, intermittent screening and treatment (ISTp) has been proposed as an alternative. The objective of this study was to explore the acceptability of ISTp for health workers and pregnant women. METHODS: Semi-structured interviews of ten health workers and five focus group discussions of 38 women enrolled in an ongoing trial comparing IPTp-SP and ISTp with dihydroartemisinin-piperaquine (DP) were conducted at two antenatal clinics in rural Malawi. All transcripts were coded and themes were identified using a content analysis approach. RESULTS: Amongst health workers, there were contrasting opinions on the preference of blood sampling methods, and the influence of method on reliability of diagnosis. The perceived greater effectiveness of DP compared to SP was appreciated, however concerns of user compliance with the full dose of DP in non-trial settings were raised. Despite the discomfort of repeated finger pricks, pregnant women were generally accepting of ISTp, particularly the chance for regular blood tests to check for infections and the perceived greater effectiveness with fewer side effects of DP compared to SP. CONCLUSION: In the trial context, pregnant women tended to prefer ISTp-DP over IPTp-SP. Health workers were also accepting of ISTp-DP as an alternative to IPTp-SP in light of increasing SP resistance. However, reliability of stock, adherence to malaria test results and user adherence to the full course of DP may present barriers to successful routine implementation. Effective communication with health workers and between health workers, pregnant women and their communities will be essential for the acceptability of focused antenatal care, including the best malaria control measures available.


Assuntos
Pessoal de Saúde , Malária/diagnóstico , Malária/tratamento farmacológico , Aceitação pelo Paciente de Cuidados de Saúde , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Gestantes , Adolescente , Adulto , Antimaláricos/uso terapêutico , Feminino , Humanos , Recém-Nascido , Entrevistas como Assunto , Malaui , Programas de Rastreamento/métodos , Gravidez , Adulto Jovem
14.
PLoS One ; 6(7): e22491, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21811621

RESUMO

HIV infection increases the burden of disease of malaria in pregnancy, in part by impairing the development of immunity. We measured total IgG and phagocytic antibodies against variant surface antigens of placental-type CS2 parasites in 187 secundigravidae (65% HIV infected). In women with placental malaria infection, phagocytic antibodies to CS2(VSA) were decreased in the presence of HIV (p = 0.011) and correlated positively with infant birth weight (coef = 3.57, p = 0.025), whereas total IgG to CS2(VSA) did not. Phagocytic antibodies to CS2(VSA) are valuable tools to study acquired immunity to malaria in the context of HIV co-infection. Secundigravidae may be an informative group for identification of correlates of immunity.


Assuntos
Anticorpos Antiprotozoários/imunologia , Eritrócitos/patologia , Eritrócitos/parasitologia , Infecções por HIV/complicações , Malária/complicações , Malária/imunologia , Fagocitose/imunologia , Antígenos de Protozoários/imunologia , Peso ao Nascer/imunologia , Estudos de Coortes , Feminino , HIV/fisiologia , Infecções por HIV/imunologia , Hemoglobinas/metabolismo , Humanos , Lactente , Placenta/parasitologia , Placenta/patologia , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Resultado do Tratamento , Adulto Jovem
15.
J Infect Dis ; 203(4): 464-72, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21216867

RESUMO

BACKGROUND: Effectiveness of cotrimoxazole (CTX) compared with sulfadoxine-pyrimethamine (SP) intermittent-preventive-therapy (IPTp) for malaria in HIV-infected pregnant women is unknown. We examined effectiveness of CTX with or without SP-IPTp versus SP-IPTp at reducing malaria parasitemia and anemia. METHODS: From 2005 to 2009, we conducted a cross-sectional study of HIV-infected pregnant women at Thyolo Hospital, Malawi. Blood was tested for malaria parasitemia and anemia (hemoglobin<11 g/dl). Data were collected on use of anti-malaria interventions and other risk factors. CTX prophylaxis policy for HIV-infected pregnant women was introduced in 2007, but implementation problems resulted in some women receiving both CTX and SP-IPTp. FINDINGS: We enrolled 1,142 women, of whom 1,121 had data on CTX and/or SP-IPTp intake. Of these, 49.7%, 29.8%, and 15.4% reported taking SP-IPTp only, CTX only and SP-IPTp plus CTX, respectively. Compared with women taking SP-IPTp, those taking SP-IPTp plus CTX and CTX were less likely to have malaria parasitemia (OR, [95%CI]: 0.09, [0.01-0.66] and 0.43, [0.19-0.97], respectively) or anemia (PR, [95% CI]: 0.67, [0.54-0.83] and 0.72, [0.61-0.83], respectively). CONCLUSION: In HIV-infected pregnant women, daily CTX was associated with reduced malaria parasitemia and anemia compared with SP-IPTp. CTX plus SP-IPTp was associated with further reduction in malaria parasitemia but toxicity was not fully assessed.


Assuntos
Anemia/epidemiologia , Infecções por HIV/complicações , Malária/epidemiologia , Parasitemia/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adolescente , Adulto , Anemia/prevenção & controle , Antimaláricos/uso terapêutico , Quimioprevenção/métodos , Estudos Transversais , Combinação de Medicamentos , Feminino , Humanos , Malária/complicações , Malária/parasitologia , Malária/prevenção & controle , Malaui/epidemiologia , Pessoa de Meia-Idade , Parasitemia/prevenção & controle , Gravidez , Prevalência , Resultado do Tratamento , Adulto Jovem
16.
PLoS One ; 5(5): e10807, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20520838

RESUMO

BACKGROUND: Pregnant women residing in malaria endemic areas are highly susceptible to Plasmodium falciparum malaria, particularly during their first pregnancy, resulting in low birth weight babies and maternal anaemia. This susceptibility is associated with placental sequestration of parasitised red blood cells expressing pregnancy-specific variant surface antigens. Acquisition of antibodies against these variant surface antigens may protect women and their offspring. Functions of such antibodies may include prevention of placental sequestration or opsonisation of parasitised cells for phagocytic clearance. METHODOLOGY/FINDINGS: Here we report the development and optimisation of a new high-throughput flow cytometry-based phagocytosis assay using undifferentiated Thp-1 cells to quantitate the amount of opsonizing antibody in patient sera, and apply this assay to measure the impact of HIV on the levels of antibodies to a pregnancy malaria-associated parasite line in a cohort of Malawian primigravid women. The assay showed high reproducibility, with inter-experimental correlation of r(2) = 0.99. In primigravid women, concurrent malaria infection was associated with significantly increased antibodies, whereas HIV decreased the ability to acquire opsonising antibodies (Mann-Whitney ranksum: p = 0.013). This decrease was correlated with HIV-induced immunosuppression, with women with less than 350 x 10(6) CD4+ T- cells/L having less opsonising antibodies (coef: -11.95,P = 0.002). Levels of antibodies were not associated with protection from low birth weight or anaemia. CONCLUSIONS/SIGNIFICANCE: This flow cytometry-based phagocytosis assay proved to be efficient and accurate for the measurement of Fc-receptor mediated phagocytosis-inducing antibodies in large cohorts. HIV was found to affect mainly the acquisition of antibodies to pregnancy-specific malaria in primigravidae. Further studies of the relationship between opsonising antibodies to malaria in pregnancy and HIV are indicated.


Assuntos
Anticorpos Antiprotozoários/imunologia , Especificidade de Anticorpos/imunologia , HIV/imunologia , Imunoensaio/métodos , Malária Falciparum/imunologia , Fagocitose/imunologia , Complicações Parasitárias na Gravidez/imunologia , Anemia/complicações , Anemia/imunologia , Antígenos de Protozoários/imunologia , Diferenciação Celular , Linhagem Celular , Estudos de Coortes , Feminino , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/parasitologia , Hemoglobinas/metabolismo , Humanos , Imunoglobulina G/imunologia , Recém-Nascido de Baixo Peso/imunologia , Recém-Nascido , Malária Falciparum/complicações , Malária Falciparum/patologia , Gravidez
17.
Diagn Microbiol Infect Dis ; 66(4): 356-60, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20226326

RESUMO

There are limited data on acute HIV infection (AHI) prevalence during pregnancy. Malawian pregnant women admitted in the third trimester and meeting eligibility criteria underwent dual HIV rapid antibody testing. AHI prevalence was retrospectively detected through HIV RNA pooling of seronegative plasma. Among 3,825 pregnant women screened, dual HIV rapid testing indicated that 30.2% were HIV positive, 69.7% were HIV negative, and 0.1% were indeterminate. Sensitivity and specificity of dual rapid testing was 99.0% and 98.7%, respectively. Of 2,666 seronegative specimens, 2,327 had samples available for HIV RNA pooling; 5 women (0.21%) (95% confidence interval, 0.03-0.40%) had AHI with a median peripartum viral load of 1,324,766 copies/mL. Pregnant women are at risk for AHI, warranting counseling of all women and their sexual partners about incident HIV during pregnancy. Dual HIV rapid tests have high sensitivity and specificity. HIV testing should be repeated in the third trimester and/or at delivery.


Assuntos
Infecções por HIV/epidemiologia , HIV/isolamento & purificação , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Feminino , Anticorpos Anti-HIV/sangue , Humanos , Malaui/epidemiologia , Gravidez , Gestantes , Prevalência , RNA Viral/sangue , Sensibilidade e Especificidade , Virologia/métodos , Adulto Jovem
18.
Clin Vaccine Immunol ; 16(3): 312-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19129467

RESUMO

Human immunodeficiency virus type 1 (HIV-1) coinfection decreases antibodies to variant surface antigens implicated in pregnancy-associated malaria (VSA-PAM) caused by Plasmodium falciparum. The effect of HIV-1 on antibody functions that may protect mothers from pregnancy-associated malaria is unknown. Sera from multigravid pregnant women with malaria and HIV-1 coinfection (n=58) or malaria alone (n=29) and from HIV-1-infected (n=102) or -uninfected (n=54) multigravidae without malaria were analyzed for anti-VSA-PAM antibodies by flow cytometry, the ability to inhibit adhesion to chondroitin sulfate A, or to opsonize CS2-infected erythrocytes for phagocytosis by THP-1 cells. In women with malaria, anti-VSA-PAM levels correlated better with opsonic activity (r=0.60) than with adhesion-blocking activity (r=0.33). In univariate analysis, HIV-1 coinfection was associated with lower opsonic activity but not adhesion-blocking activity or anti-VSA-PAM levels. Malaria-infected women with anemia (hemoglobin levels of <11.0 g/dl) had lower opsonic activity than nonanemic women (P=0.007) independent of HIV-1 status. By multivariate analysis, in malaria-infected women, anemia (but not HIV status) was associated with opsonic activity. In women without malaria, opsonic activity was not associated with either anemia or HIV-1 status. In multigravid pregnant women with malaria, impaired serum opsonic activity may contribute to anemia and possibly to the decreased immunity to pregnancy-associated malaria associated with HIV-1.


Assuntos
Anemia/etiologia , Anticorpos Antiprotozoários/sangue , Infecções por HIV/complicações , Malária Falciparum/complicações , Malária Falciparum/imunologia , Plasmodium falciparum/imunologia , Complicações Infecciosas na Gravidez/imunologia , Adulto , Animais , Antígenos de Protozoários/imunologia , Antígenos de Superfície/imunologia , Feminino , HIV/isolamento & purificação , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Recém-Nascido , Proteínas Opsonizantes/imunologia , Gravidez
19.
J Infect Dis ; 197(10): 1378-81, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18444794

RESUMO

BACKGROUND: The mechanism of mother-to-child transmission (MTCT) of HIV-1 is not well described. METHODS: Of 328 HIV-infected mother-infant pairs, we identified 91 that had discordant angiotensin I-converting enzyme and glutathione S-transferase M1 alleles. Maternal alleles in cord blood were quantified with real-time polymerase chain reaction, as indicators of microtransfusions. RESULTS: HIV-1 infected infants had more maternal DNA in cord blood than their uninfected counterparts. Increased maternal DNA in cord blood was associated with preterm delivery, low birth weight, and maternal immunosuppression. CONCLUSION: Intrapartum MTCT was associated with placental microtransfusions. The associations among placental microtransfusion, in-utero MTCT, maternal immunosuppression, and poor birth outcome should be further investigated.


Assuntos
Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas , Alelos , DNA/genética , DNA/isolamento & purificação , Feminino , Sangue Fetal/química , Glutationa Transferase/genética , HIV , Infecções por HIV/genética , Humanos , Recém-Nascido , Malaui , Mães , Peptidil Dipeptidase A/genética , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez
20.
J Infect Dis ; 197(5): 757-65, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18279052

RESUMO

BACKGROUND: Placental malaria causes fetal growth retardation (FGR), which has been linked epidemiologically to placental monocyte infiltrates. We investigated whether parasite or monocyte infiltrates were associated with placental hypoxia, as a potential mechanism underlying malarial FGR. METHODS: We studied the hypoxia markers hypoxia inducible factor (HIF)-1alpha, vascular endothelial growth factor (VEGF), placental growth factor, VEGF receptor 1 and its soluble form, and VEGF receptor 2. We used real-time polymerase chain reaction (in 59 women) to examine gene transcription, immunohistochemistry (in 30 women) to describe protein expression, and laser-capture microdissection (in 23 women) to examine syncytiotrophoblast-specific changes in gene expression. We compared gene and protein expression in relation to malaria infection, monocyte infiltrates, and birth weight. RESULTS: We could not associate any hallmark of placental malaria with a transcription, expression, or tissue-distribution profile characteristic of a response to hypoxia, but we found higher HIF-1alpha levels (P= .0005) and lower VEGF levels (P= .0026) in the syncytiotrophoblasts of cases of malaria than in those of asymptomatic control placentas. CONCLUSIONS: Our data are inconsistent with a role for placental hypoxia in the pathogenesis of malaria-associated FGR. The laser-capture microdissection study was small, but its results suggest (1) that malaria affects syncytiotrophoblast-gene transcription and (2) novel potential mechanisms for placental malaria-associated FGR.


Assuntos
Retardo do Crescimento Fetal/parasitologia , Hipóxia Fetal/parasitologia , Malária/complicações , Placenta/parasitologia , Plasmodium malariae/patogenicidade , Complicações Parasitárias na Gravidez/fisiopatologia , Adulto , Animais , Estudos de Casos e Controles , Vilosidades Coriônicas/metabolismo , Vilosidades Coriônicas/parasitologia , Feminino , Retardo do Crescimento Fetal/metabolismo , Perfilação da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Recém-Nascido de Baixo Peso , Recém-Nascido , Monócitos/parasitologia , Monócitos/patologia , Placenta/metabolismo , Placenta/patologia , Fator de Crescimento Placentário , Gravidez , Proteínas da Gravidez/metabolismo , Estudos Prospectivos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
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