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1.
medRxiv ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38559091

RESUMO

Background: Tororo District, Uganda experienced a dramatic decrease in malaria burden from 2015-19 following 5 years of indoor residual spraying (IRS) with carbamate (Bendiocarb) and then organophosphate (Actellic) insecticides. However, a marked resurgence occurred in 2020, which coincided with a change to a clothianidin-based IRS formulations (Fludora Fusion/SumiShield). To quantify the magnitude of the resurgence, investigate causes, and evaluate the impact of a shift back to IRS with Actellic in 2023, we assessed changes in malaria metrics in regions within and near Tororo District. Methods: Malaria surveillance data from Nagongera Health Center, Tororo District was included from 2011-2023. In addition, a cohort of 667 residents from 84 houses was followed from August 2020 through September 2023 from an area bordering Tororo and neighboring Busia District, where IRS has never been implemented. Cohort participants underwent passive surveillance for clinical malaria and active surveillance for parasitemia every 28 days. Mosquitoes were collected in cohort households every 2 weeks using CDC light traps. Female Anopheles were speciated and tested for sporozoites and phenotypic insecticide resistance. Temporal comparisons of malaria metrics were stratified by geographic regions. Findings: At Nagongera Health Center average monthly malaria cases varied from 419 prior to implementation of IRS; to 56 after 5 years of IRS with Bendiocarb and Actellic; to 1591 after the change in IRS to Fludora Fusion/SumiShield; to 155 after a change back to Actellic. Among cohort participants living away from the border in Tororo, malaria incidence increased over 8-fold (0.36 vs. 2.97 episodes per person year, p<0.0001) and parasite prevalence increased over 4-fold (17% vs. 70%, p<0.0001) from 2021 to 2022 when Fludora Fusion/SumiShield was used. Incidence decreased almost 5-fold (2.97 vs. 0.70, p<0.0001) and prevalence decreased by 39% (70% vs. 43%, p<0.0001) after shifting back to Actellic. There was a similar pattern among those living near the border in Tororo, with increased incidence between 2021 and 2022 (0.93 vs. 2.40, p<0.0001) followed by a decrease after the change to Actellic (2.40 vs. 1.33, p<0.001). Among residents of Busia, malaria incidence did not change significantly over the 3 years of observation. Malaria resurgence in Tororo was temporally correlated with the replacement of An. gambiae s.s. by An. funestus as the primary vector, with a marked decrease in the density of An. funestus following the shift back to IRS with Actellic. In Busia, An. gambiae s.s. remained the primary vector throughout the observation period. Sporozoite rates were approximately 50% higher among An. funestus compared to the other common malaria vectors. Insecticide resistance phenotyping of An. funestus revealed high tolerance to clothianidin, but full susceptibility to Actellic. Conclusions: A dramatic resurgence of malaria in Tororo was temporally associated with a change to clothianidin-based IRS formulations and emergence of An. funestus as the predominant vector. Malaria decreased after a shift back to IRS with Actellic. This study highlights the ability of malaria vectors to rapidly circumvent control efforts and the importance of high-quality surveillance systems to assess the impact of malaria control interventions and generate timely, actionable data.

2.
Am J Trop Med Hyg ; 107(5): 1028-1035, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36191870

RESUMO

Highly effective vector control can reduce malaria burden significantly, but individuals with parasitemia provide a potential reservoir for onward transmission. We performed an empirical, non-parametric simulation based on cohort data from Tororo District, Uganda-an area with historically high but recently reduced malaria transmission-to estimate the effects of mass drug administration (MDA) and test-and-treat on parasite prevalence. We estimate that a single round of MDA would have accelerated declines in parasite prevalence dramatically over 2 years (cumulative parasite prevalence ratio [PPR], 0.34). This decline was mostly during the first year of administration (PPR, 0.23) and waned by 23 months (PPR, 0.74). Test-and-treat using a highly sensitive diagnostic had nearly the same effect as MDA at 1 year (PPR, 0.27) and required many fewer treatments. The impact of test-and-treat using a standard diagnostic was modest (PPR, 0.58 at 1 year). Our analysis suggests that in areas experiencing a dramatic reduction in malaria prevalence, MDA or test-and-treat with a highly sensitive diagnostic may be an effective way of reducing or eliminating the infectious reservoir temporarily. However, for sustained benefits, repeated rounds of the intervention or additional interventions are required.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Humanos , Administração Massiva de Medicamentos , Uganda/epidemiologia , Malária/diagnóstico , Malária/tratamento farmacológico , Malária/epidemiologia , Parasitemia/diagnóstico , Parasitemia/tratamento farmacológico , Parasitemia/epidemiologia , Prevalência , Antimaláricos/uso terapêutico , Malária Falciparum/epidemiologia
3.
J Infect Dis ; 226(4): 708-713, 2022 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-35578987

RESUMO

Achieving malaria elimination requires a better understanding of the transmissibility of human infections in different transmission settings. This study aimed to characterize the human infectious reservoir in a high endemicity setting in eastern Uganda, using gametocyte quantification and mosquito feeding assays. In asymptomatic infections, gametocyte densities were positively associated with the proportion of infected mosquitoes (ß = 1.60; 95% CI, 1.32-1.92; P < .0001). Combining transmissibility and abundance in the population, symptomatic and asymptomatic infections were estimated to contribute to 5.3% and 94.7% of the infectious reservoir, respectively. School-aged children (5-15 years old) contributed to 50.4% of transmission events and were important drivers of malaria transmission.


Assuntos
Anopheles , Linfoma de Burkitt , Malária Falciparum , Malária , Adolescente , Animais , Infecções Assintomáticas/epidemiologia , Criança , Pré-Escolar , Humanos , Malária/epidemiologia , Malária Falciparum/epidemiologia , Plasmodium falciparum , Uganda/epidemiologia
4.
J Perinatol ; 42(2): 181-186, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35067676

RESUMO

OBJECTIVE: Our study sought to determine whether metabolites from a retrospective collection of banked cord blood specimens could accurately estimate gestational age and to validate these findings in cord blood samples from Busia, Uganda. STUDY DESIGN: Forty-seven metabolites were measured by tandem mass spectrometry or enzymatic assays from 942 banked cord blood samples. Multiple linear regression was performed, and the best model was used to predict gestational age, in weeks, for 150 newborns from Busia, Uganda. RESULTS: The model including metabolites and birthweight, predicted the gestational ages within 2 weeks for 76.7% of the Ugandan cohort. Importantly, this model estimated the prevalence of preterm birth <34 weeks closer to the actual prevalence (4.67% and 4.00%, respectively) than a model with only birthweight which overestimates the prevalence by 283%. CONCLUSION: Models that include cord blood metabolites and birth weight appear to offer improvement in gestational age estimation over birth weight alone.


Assuntos
Sangue Fetal , Nascimento Prematuro , Peso ao Nascer , Feminino , Sangue Fetal/metabolismo , Idade Gestacional , Humanos , Recém-Nascido , Metabolômica/métodos , Gravidez , Estudos Retrospectivos
5.
Am J Trop Med Hyg ; 106(3): 850-852, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35026727

RESUMO

Rapid diagnostic tests (RDTs) for Plasmodium falciparum commonly detect histidine-rich protein 2 (HRP-2), but HRP-2 deletions are increasingly recognized. We evaluated a prototype test detecting parasite lactate dehydrogenase (pLDH) and compared it to commercially available RDTs at a health facility in Uganda, using quantitative polymerase chain reaction as a gold standard. The prototype pLDH test had a high sensitivity for infections with at least 100 parasites/µL (98%), comparable to HRP-2, and greater than an existing pLDH RDT (89%). Specificity for the prototype test was 99.5%, which is greater than the HRP-2 tests (93-95%). Therefore, the prototype pLDH test may be an attractive alternative malaria diagnostic.


Assuntos
Malária Falciparum , Malária , Antígenos de Protozoários/análise , Testes Diagnósticos de Rotina , Humanos , L-Lactato Desidrogenase/análise , Malária/diagnóstico , Malária Falciparum/diagnóstico , Malária Falciparum/parasitologia , Microscopia , Plasmodium falciparum , Reação em Cadeia da Polimerase , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Sensibilidade e Especificidade , Uganda
6.
Lancet Infect Dis ; 21(11): 1568-1578, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34146476

RESUMO

BACKGROUND: Symptomatic malaria cases reflect only a small proportion of all Plasmodium spp infections. Many infected individuals are asymptomatic, and persistent asymptomatic Plasmodium falciparum infections are common in endemic settings. We aimed to quantify the contribution of symptomatic and asymptomatic infections to P falciparum transmission in Tororo, Uganda. METHODS: We did a longitudinal, observational cohort study in Tororo district, Uganda. We recruited participants of all ages from randomly selected households within this district. Participants were eligible if the selected household had no more than nine permanent residents and at least two members younger than 10 years, and the household was their primary residence, and they agreed to come to the study clinic for any fever episode and avoid antimalarial medications outside the study. Participants were followed-up by continuous passive surveillance for the incidence of symptomatic infections; routine assessments (ie, standardised clinical evaluation and blood samples) were done at baseline and at routine visits every 4 weeks for 2 years. P falciparum parasite density, gametocyte density, and genetic composition were determined molecularly using quantitative PCR (qPCR), quantitative reverse transcriptase PCR (qRT-PCR), and amplicon deep sequencing, respectively. Membrane feeding assays were also done to assess infectivity to mosquitoes. The contribution of different populations to the infectious reservoir was estimated for symptomatic infections, asymptomatic but microscopically detected infections, and asymptomatic but qPCR-detected infections; and for age groups younger than 5 years, 5-15 years, and 16 years or older. FINDINGS: Between Oct 4, 2017, and Oct 31, 2019, 531 individuals were enrolled from 80 randomly selected households and were followed-up for 2 years. At baseline, P falciparum was detected in 28 (5·3%) of 531 participants by microscopy and an additional 64 (12·1%) by qPCR and declined thereafter. In 538 mosquito feeding experiments on 107 individuals, 446 (1·2%) of 37 404 mosquitoes became infected, with mosquito infection rates being strongly associated with gametocyte densities (ß=2·11, 95% CI 1·62-2·67; p<0·0001). Considering both transmissibility of infections and their relative frequency, the estimated human infectious reservoir consisted primarily of asymptomatic microscopy-detected infections (83·8%), followed by asymptomatic submicroscopic infections (15·6%), and symptomatic infections (0·6%). Children aged 5-15 years accounted for more than half of the infectious reservoir (58·7%); individuals younger than 5 years (25·8%) and those 16 years or older (15·6%) contributed less. Samples from four children contribued to 279 (62·6%) of 446 infected mosquitoes after multiple mosquito-feeding assays. INTERPRETATION: Individuals with asymptomatic infections were important drivers of malaria transmission. School-aged children contributed to more than half of all mosquito infections, with a small minority of asymptomatic children being highly infectious. Demographically targeted interventions, aimed at school-aged children, could further reduce transmission in areas under effective vector control. FUNDING: US National Institutes of Health, Bill & Melinda Gates Foundation, and the European Research Council.


Assuntos
Anopheles/parasitologia , Malária Falciparum/prevenção & controle , Malária Falciparum/transmissão , Plasmodium falciparum/fisiologia , Adolescente , Animais , Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/administração & dosagem , Combinação Arteméter e Lumefantrina/uso terapêutico , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Masculino , Uganda/epidemiologia
7.
J Infect Dis ; 224(12): 2105-2112, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34010401

RESUMO

BACKGROUND: Placental malaria has been associated with increased cord blood maternal microchimerism (MMc), which in turn may affect susceptibility to malaria in the offspring. We sought to determine the impact of maternal peripheral Plasmodium falciparum parasitemia during pregnancy on MMc and to determine whether maternal cells expand during primary parasitemia in the offspring. METHODS: We conducted a nested cohort study of maternal-infant pairs from a prior pregnancy malaria chemoprevention study. Maternal microchimerism was measured by quantitative polymerase chain reaction targeting a maternal-specific marker in genomic DNA from cord blood, first P falciparum parasitemia, and preparasitemia. Logistic and negative binomial regression were used to assess the impact of maternal peripheral parasitemia, symptomatic malaria, and placental malaria on cord blood MMc. Generalized estimating equations were used to assess predictors of MMc during infancy. RESULTS: Early maternal parasitemia was associated with increased detection of cord blood MMc (adjusted odds ratio = 3.91, P = .03), whereas late parasitemia, symptomatic malaria, and placental malaria were not. The first parasitemia episode in the infant was not associated with increased MMc relative to preparasitemia. CONCLUSIONS: Maternal parasitemia early in pregnancy may increase the amount of MMc acquired by the fetus. Future work should investigate the impact of this MMc on immune responses in the offspring.


Assuntos
Quimerismo/estatística & dados numéricos , Malária Falciparum/genética , Doenças Placentárias/genética , Plasmodium falciparum/isolamento & purificação , Complicações Parasitárias na Gravidez/genética , Adolescente , Adulto , Estudos de Coortes , Suscetibilidade a Doenças , Feminino , Humanos , Malária Falciparum/diagnóstico , Malária Falciparum/epidemiologia , Saúde Materna , Parasitemia/epidemiologia , Placenta/parasitologia , Doenças Placentárias/epidemiologia , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia
9.
Lancet Infect Dis ; 19(9): 962-972, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31307883

RESUMO

BACKGROUND: Intermittent preventive treatment (IPT) of malaria with dihydroartemisinin-piperaquine is a promising strategy for malaria prevention in young African children. However, the optimal dosing strategy is unclear and conflicting evidence exists regarding the risk of malaria after cessation of chemoprevention. We aimed to compare two dosing strategies of IPT with dihydroartemisinin-piperaquine in young Ugandan children, and to evaluate the risk of malaria after cessation of IPT. METHODS: In this double-blind, randomised controlled phase 2 trial, women and their unborn children were recruited at Tororo District Hospital (Tororo, Uganda). Eligible participants were HIV-negative women aged 16 years or older with a viable pregnancy (gestational age 12-20 weeks). Women and their unborn children were randomly assigned (1:1:1:1) to one of four treatment groups, all receiving dihydroartemisinin-piperaquine, on the basis of the IPT intervention received by the woman during pregnancy: women every 8 weeks, children every 4 weeks; women every 4 weeks, children every 4 weeks; women every 8 weeks, children every 12 weeks; and women every 4 weeks, children every 12 weeks. Block randomisation was done by an independent investigator using a computer-generated randomisation list (permuted block sizes of six and 12). We analysed children on the basis of their random assignment to receive dihydroartemisinin-piperaquine (20 mg/160 mg tablets) once daily for 3 consecutive days every 4 weeks or 12 weeks. Children received study drugs from age 8 weeks to 24 months and were followed-up to age 36 months. Participants and investigators were masked to treatment allocation. The primary outcome was the incidence of symptomatic malaria during the intervention and following cessation of the intervention, adjusted for potential confounders. The primary outcome and safety were assessed in the modified intention-to-treat population, which included all children who reached 8 weeks of age and received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT02163447. FINDINGS: Between Oct 21, 2014, and May 18, 2015, 191 children were born, of whom 183 reached 8 weeks of age and received at least one dose of study drug and thus were included in the primary analysis (96 children in the 4-week group and 87 in the 12-week group). During the intervention, the incidence of symptomatic malaria was significantly lower among children treated every 4 weeks than children treated every 12 weeks; three episodes occurred among children treated every 4 weeks (incidence 0·018 episodes per person-year) compared with 61 episodes among children treated every 12 weeks (incidence 0·39 episodes per person-year; adjusted incidence rate ratio [aIRR] 0·041, 95% CI 0·012-0·150, p<0·0001). After cessation of IPT, children who had previously received dihydroartemisinin-piperaquine every 4 weeks had a lower incidence of symptomatic malaria than children who were treated every 12 weeks; 62 episodes occurred among children previously treated every 4 weeks (incidence 0·73 episodes per person-year) compared with 83 episodes among children treated every 12 weeks (incidence 1·1 episodes per person-year; aIRR 0·62, 0·40-0·95, p=0·028). In the 4-week group, 94 (98%) of 96 children had adverse events versus 87 (100%) of 87 children in the 12-week group. The most commonly reported adverse event was cough in both treatment groups (94 [98%] in the 4-week group vs 87 [100%] in the 12-week group). 16 children had severe adverse events (seven [7%] children in the 4-week group vs nine [10%] children in the 12-week group). No severe adverse events were thought to be related to study drug administration. One death occurred during the intervention (age 8 weeks to 24 months), which was due to respiratory failure unrelated to malaria. INTERPRETATION: IPT with dihydroartemisinin-piperaquine given every 4 weeks was superior to treatment every 12 weeks for the prevention of malaria during childhood, and this protection was extended for up to 1 year after cessation of IPT. FUNDING: Eunice Kennedy Shriver National Institute of Child Health and Human Development.


Assuntos
Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Quinolinas/administração & dosagem , Anemia/epidemiologia , Anemia/parasitologia , Antimaláricos/efeitos adversos , Artemisininas/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Incidência , Lactente , Malária Falciparum/diagnóstico , Masculino , Parasitemia/epidemiologia , Parasitemia/parasitologia , Quinolinas/efeitos adversos , Medição de Risco , Uganda/epidemiologia , Suspensão de Tratamento
10.
Sci Rep ; 9(1): 6758, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043691

RESUMO

Women living with HIV (WLHIV) have an increased risk of malaria in pregnancy (MiP). It is unclear if MiP in WLHIV causes a systemic inflammatory response and increases the risk of adverse birth outcomes, especially for women receiving antiretroviral therapy (ART) and daily trimethoprim-sulfamethoxazole (TMP/SXT). We analyzed repeated plasma samples in a cohort of malaria-exposed Ugandan WLHIV receiving ART and daily TMP/SXT to examine changes in inflammatory markers across pregnancy and their association with birth outcomes. Concentrations of CHI3L1, CRP, IL-18BP, IL-6, sICAM-1, and sTNFR2 were quantified by ELISA in 1115 plasma samples collected over pregnancy from 326 women. MiP was associated with increased sTNFR2, sICAM-1 and IL-18BP concentrations across pregnancy. Women who delivered preterm had elevated concentrations of sTNFR2 and altered levels of IL-6 during pregnancy. Women with sTNFR2 concentrations in the highest quartile within 6 weeks of delivery had an increased relative risk of preterm birth. Our results indicate that despite daily TMP/SXT, MiP in WLHIV induced a systemic inflammatory response that was associated with an increased risk of preterm birth. These findings highlight the need for additional strategies to protect WLHIV from malaria infection in pregnancy to promote healthy outcomes for mother and child.


Assuntos
Antirretrovirais/administração & dosagem , Infecções por HIV/complicações , HIV/isolamento & purificação , Inflamação/etiologia , Malária/epidemiologia , Nascimento Prematuro/epidemiologia , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem , Adulto , Estudos de Coortes , Feminino , HIV/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Incidência , Recém-Nascido , Inflamação/patologia , Malária/virologia , Gravidez , Nascimento Prematuro/virologia , Prognóstico , Fatores de Risco , Uganda/epidemiologia
11.
PLoS One ; 14(4): e0215058, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973949

RESUMO

BACKGROUND: Preterm birth (PTB) is a leading cause of neonatal mortality and longer-term morbidity. Acute chorioamnionitis (ACA) is a common cause of PTB, however, there are limited data on the prevalence of ACA and its association with PTB in resource limited settings. METHODS: Data and samples came from a clinical trial evaluating novel strategies for the prevention of malaria in HIV infected pregnant women in Uganda. Women were enrolled between 12-28 weeks of gestation and followed through delivery. For each placenta delivered, three placental tissue types (membrane roll, umbilical cord and chorionic plate/villous parenchyma) were collected. Slides were assessed for diagnosis of maternal and fetal ACA by microscopic evaluation of neutrophilic infiltration using a standardized grading scale. The primary outcomes were PTB (<37 weeks), low birth weight (LBW, <2500 grams), and small-for-gestational age (SGA, birth weight <10th percentile for age). Univariate and multivariate logistic regression were used to estimate associations between 1) maternal characteristics (age, education, wealth, gravidity, gestational age at enrollment, placental malaria, anti-malarial prophylaxis treatment regimen, HIV disease parameters) and ACA, and 2) associations between ACA and adverse birth outcomes. FINDINGS: A total of 193 placentas were included in the analysis. The prevalence of maternal and fetal ACA was 44.5% and 28.0%, respectively. HIV infected women between 28-43 years of age had a higher risk of maternal ACA compared to those between 17-21 years of age (50.9% vs. 19.1%; aOR = 4.00 (1.10-14.5), p = 0.04) and the diagnosis of severe maternal ACA was associated with a significantly higher risk of PTB (28.6% vs. 6.0%; aOR = 6.04 (1.87-19.5), p = 0.003), LBW (33.3% vs. 9.4%; aOR = 4.86 (1.65-14.3); p = 0.004), and SGA (28.6% vs. 10.1%; aOR = 3.70 (1.20-11.4), p = 0.02). No maternal characteristics were significantly associated with fetal ACA and the diagnosis of fetal ACA was not associated with adverse birth outcomes. CONCLUSIONS: Histological evidence of severe maternal ACA was associated with an increased risk of PTB, LBW, and SGA in HIV infected, pregnant Ugandan women.


Assuntos
Corioamnionite/fisiopatologia , Retardo do Crescimento Fetal/etiologia , Infecções por HIV/complicações , HIV/isolamento & purificação , Recém-Nascido Pequeno para a Idade Gestacional , Complicações Infecciosas na Gravidez/etiologia , Doença Aguda , Adolescente , Adulto , Peso ao Nascer , Método Duplo-Cego , Feminino , Retardo do Crescimento Fetal/patologia , Infecções por HIV/epidemiologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez , Uganda/epidemiologia , Adulto Jovem
12.
Malar J ; 18(1): 144, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31014336

RESUMO

BACKGROUND: Malaria in pregnancy is a major public health challenge, but its risk factors remain poorly understood in some settings. This study assessed the association between household and maternal characteristics and malaria among pregnant women in a high transmission area of Uganda. METHODS: A nested prospective study was conducted between 6th September 2016 and 5th December 2017 in Busia district. 782 HIV uninfected women were enrolled in the parent study with convenience sampling. Socioeconomic and house construction data were collected via a household survey after enrolment. Homes were classified as modern (plaster or cement walls, metal or wooden roof and closed eaves) or traditional (all other homes). Maternal and household risk factors were evaluated for three outcomes: (1) malaria parasitaemia at enrolment, measured by thick blood smear and qPCR, (2) malaria parasitaemia during pregnancy following initiation of IPTp, measured by thick blood smear and qPCR and (3) placental malaria measured by histopathology. RESULTS: A total of 753 of 782 women were included in the analysis. Most women had no or primary education (75%) and lived in traditional houses (77%). At enrolment, microscopic or sub-microscopic parasitaemia was associated with house type (traditional versus modern: adjusted risk ratio (aRR) 1.29, 95% confidence intervals 1.15-1.45, p < 0.001), level of education (primary or no education versus O-level or beyond: aRR 1.13, 95% confidence interval 1.02-1.24, p = 0.02), and gravidity (primigravida versus multigravida: aRR 1.10, 95% confidence interval 1.02-1.18, p = 0.009). After initiation of IPTp, microscopic or sub-microscopic parasitaemia was associated with wealth index (poorest versus least poor: aRR 1.24, 95% CI 1.10-1.39, p < 0.001), house type (aRR 1.14, 95% CI 1.01-1.28, p = 0.03), education level (aRR 1.19, 95% CI 1.06-1.34, p = 0.002) and gravidity (aRR 1.32, 95% CI 1.20-1.45, p < 0.001). Placental malaria was associated with gravidity (aRR 2.87, 95% CI 2.39-3.45, p < 0.001), but not with household characteristics. CONCLUSIONS: In an area of high malaria transmission, primigravid women and those belonging to the poorest households, living in traditional homes and with the least education had the greatest risk of malaria during pregnancy.


Assuntos
Características da Família , Malária/epidemiologia , Complicações Parasitárias na Gravidez/epidemiologia , Adolescente , Adulto , Antimaláricos/uso terapêutico , Escolaridade , Doenças Endêmicas , Feminino , Humanos , Malária/tratamento farmacológico , Mães , Razão de Chances , Gravidez , Estudos Prospectivos , Fatores de Risco , Fatores Socioeconômicos , Uganda/epidemiologia , Adulto Jovem
13.
PLoS Med ; 15(7): e1002606, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30016328

RESUMO

BACKGROUND: Intermittent preventive treatment of malaria in pregnancy (IPTp) with dihydroartemisinin-piperaquine (IPTp-DP) has been shown to reduce the burden of malaria during pregnancy compared to sulfadoxine-pyrimethamine (IPTp-SP). However, limited data exist on how IPTp regimens impact malaria risk during infancy. We conducted a double-blinded randomized controlled trial (RCT) to test the hypothesis that children born to mothers given IPTp-DP would have a lower incidence of malaria during infancy compared to children born to mothers who received IPTp-SP. METHODS AND FINDINGS: We compared malaria metrics among children in Tororo, Uganda, born to women randomized to IPTp-SP given every 8 weeks (SP8w, n = 100), IPTp-DP every 8 weeks (DP8w, n = 44), or IPTp-DP every 4 weeks (DP4w, n = 47). After birth, children were given chemoprevention with DP every 12 weeks from 8 weeks to 2 years of age. The primary outcome was incidence of malaria during the first 2 years of life. Secondary outcomes included time to malaria from birth and time to parasitemia following each dose of DP given during infancy. Results are reported after adjustment for clustering (twin gestation) and potential confounders (maternal age, gravidity, and maternal parasitemia status at enrolment).The study took place between June 2014 and May 2017. Compared to children whose mothers were randomized to IPTp-SP8w (0.24 episodes per person year [PPY]), the incidence of malaria was higher in children born to mothers who received IPTp-DP4w (0.42 episodes PPY, adjusted incidence rate ratio [aIRR] 1.92; 95% CI 1.00-3.65, p = 0.049) and nonsignificantly higher in children born to mothers who received IPT-DP8w (0.30 episodes PPY, aIRR 1.44; 95% CI 0.68-3.05, p = 0.34). However, these associations were modified by infant sex. Female children whose mothers were randomized to IPTp-DP4w had an apparently 4-fold higher incidence of malaria compared to female children whose mothers were randomized to IPTp-SP8w (0.65 versus 0.20 episodes PPY, aIRR 4.39, 95% CI 1.87-10.3, p = 0.001), but no significant association was observed in male children (0.20 versus 0.28 episodes PPY, aIRR 0.66, 95% CI 0.25-1.75, p = 0.42). Nonsignificant increases in malaria incidence were observed among female, but not male, children born to mothers who received DP8w versus SP8w. In exploratory analyses, levels of malaria-specific antibodies in cord blood were similar between IPTp groups and sex. However, female children whose mothers were randomized to IPTp-DP4w had lower mean piperaquine (PQ) levels during infancy compared to female children whose mothers received IPTp-SP8w (coef 0.81, 95% CI 0.65-1.00, p = 0.048) and male children whose mothers received IPTp-DP4w (coef 0.72, 95% CI 0.57-0.91, p = 0.006). There were no significant sex-specific differences in PQ levels among children whose mothers were randomized to IPTp-SP8w or IPTp-DP8w. The main limitations were small sample size and childhood provision of DP every 12 weeks in infancy. CONCLUSIONS: Contrary to our hypothesis, preventing malaria in pregnancy with IPTp-DP in the context of chemoprevention with DP during infancy does not lead to a reduced incidence of malaria in childhood; in this setting, it may be associated with an increased incidence of malaria in females. Future studies are needed to better understand the biological mechanisms of in utero drug exposure on drug metabolism and how this may affect the dosing of antimalarial drugs for treatment and prevention during infancy. TRIAL REGISTRATION: ClinicalTrials.gov number NCT02163447.


Assuntos
Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Malária Falciparum/prevenção & controle , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/administração & dosagem , Quinolinas/administração & dosagem , Sulfadoxina/administração & dosagem , Adolescente , Adulto , Antimaláricos/efeitos adversos , Artemisininas/efeitos adversos , Pré-Escolar , Método Duplo-Cego , Esquema de Medicação , Combinação de Medicamentos , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Falciparum/transmissão , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/parasitologia , Pirimetamina/efeitos adversos , Quinolinas/efeitos adversos , Sulfadoxina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Uganda/epidemiologia , Adulto Jovem
14.
Clin Infect Dis ; 66(3): 428-436, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29136115

RESUMO

Background: Combination antiretroviral therapy (cART) use in pregnancy has been associated with hormonal dysregulation. We performed a secondary retrospective analysis of longitudinal progesterone and estradiol levels in pregnancy using specimens from the Protease Inhibitors to Reduce Malaria Morbidity in HIV-infected Pregnant Women study, which randomized Ugandan human immunodeficiency virus (HIV)-infected ART-naive women to initiate either lopinavir/ritonavir (LPV/r)-based or efavirenz (EFV)-based cART. Methods: Three hundred twenty-six women (160 randomized to the EFV arm and 166 women to the LPV/r arm) with at least 1 plasma sample collected during pregnancy were included. Enrollment samples collected prior to cART initiation were used as a cART-naive comparator group. Hormone levels were quantified by enzyme-linked immunosorbent assay. Results: Estradiol levels were differentially affected by the 2 cART regimens. Exposure to LPV/r was associated with an increase in estradiol (P < .0001), whereas exposure to EFV was associated with a decrease in estradiol (P < .0001), relative to the cART-naive gestationally matched comparator group. Lower estradiol levels correlated with small for gestational age (SGA) (P = .0019) and low birth weight (P = .019) in the EFV arm, while higher estradiol levels correlated with SGA in the LPV/r arm (P = .027). Although progesterone levels were similar between treatment arms, we observed an association between SGA and lower progesterone in the LPV/r arm (P = .04). No association was observed between hormone levels and preterm birth in either arm. Levels of progesterone and estradiol were lower in cases of stillbirth, and levels of both hormones declined immediately prior to stillbirth in 5 of 8 cases. Conclusions: Combination ART regimens differentially affect estradiol levels in pregnancy, a hormone critical to the maintenance of a healthy pregnancy. Identifying cART regimens that minimize perinatal HIV transmission without contributing to hormonal dysregulation represents an urgent public health priority. Clinical Trials Registration: NCT00993031.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Benzoxazinas/uso terapêutico , Estradiol/sangue , Infecções por HIV/tratamento farmacológico , Lopinavir/uso terapêutico , Ritonavir/uso terapêutico , Adulto , Alcinos , Fármacos Anti-HIV/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Benzoxazinas/efeitos adversos , Ciclopropanos , Combinação de Medicamentos , Ensaio de Imunoadsorção Enzimática , Feminino , HIV-1 , Humanos , Lopinavir/efeitos adversos , Gravidez , Complicações Infecciosas na Gravidez/virologia , Progesterona/sangue , Ritonavir/efeitos adversos , Uganda
15.
Malar J ; 16(1): 400, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28982374

RESUMO

BACKGROUND: Malaria in pregnancy has been associated with maternal morbidity, placental malaria, and adverse birth outcomes. However, data are limited on the relationships between longitudinal measures of malaria during pregnancy, measures of placental malaria, and birth outcomes. METHODS: This is a nested observational study of data from a randomized controlled trial of intermittent preventive therapy during pregnancy among 282 participants with assessment of placental malaria and delivery outcomes. HIV-uninfected pregnant women were enrolled at 12-20 weeks of gestation. Symptomatic malaria during pregnancy was measured using passive surveillance and monthly detection of asymptomatic parasitaemia using loop-mediated isothermal amplification (LAMP). Placental malaria was defined as either the presence of parasites in placental blood by microscopy, detection of parasites in placental blood by LAMP, or histopathologic evidence of parasites or pigment. Adverse birth outcomes assessed included low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA) infants. RESULTS: The 282 women were divided into three groups representing increasing malaria burden during pregnancy. Fifty-two (18.4%) had no episodes of symptomatic malaria or asymptomatic parasitaemia during the pregnancy, 157 (55.7%) had low malaria burden (0-1 episodes of symptomatic malaria and < 50% of samples LAMP+), and 73 (25.9%) had high malaria burden during pregnancy (≥ 2 episodes of symptomatic malaria or ≥ 50% of samples LAMP+). Women with high malaria burden had increased risks of placental malaria by blood microscopy and LAMP [aRR 14.2 (1.80-111.6) and 4.06 (1.73-9.51), respectively], compared to the other two groups combined. Compared with women with no malaria exposure during pregnancy, the risk of placental malaria by histopathology was higher among low and high burden groups [aRR = 3.27 (1.32-8.12) and aRR = 7.07 (2.84-17.6), respectively]. Detection of placental parasites by any method was significantly associated with PTB [aRR 5.64 (1.46-21.8)], and with a trend towards increased risk for LBW and SGA irrespective of the level of malaria burden during pregnancy. CONCLUSION: Higher malaria burden during pregnancy was associated with placental malaria and together with the detection of parasites in the placenta were associated with increased risk for adverse birth outcomes. Trial Registration Current Controlled Trials Identifier NCT02163447.


Assuntos
Malária Falciparum/epidemiologia , Placenta/parasitologia , Plasmodium falciparum/fisiologia , Complicações Infecciosas na Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Adolescente , Adulto , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Malária Falciparum/complicações , Malária Falciparum/parasitologia , Parasitemia/parasitologia , Gravidez , Complicações Infecciosas na Gravidez/parasitologia , Nascimento Prematuro/parasitologia , Prevalência , Uganda/epidemiologia , Adulto Jovem
16.
Am J Obstet Gynecol ; 217(6): 684.e1-684.e17, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29031892

RESUMO

BACKGROUND: Angiogenic processes in the placenta are critical regulators of fetal growth and impact birth outcomes, but there are limited data documenting these processes in HIV-infected women or women from low-resource settings. OBJECTIVE: We sought to determine whether angiogenic factors are associated with adverse birth outcomes in HIV-infected pregnant women started on antiretroviral therapy. STUDY DESIGN: This is a secondary analysis of samples collected as part of a clinical trial randomizing pregnant women and adolescents infected with HIV to lopinavir/ritonavir-based (n = 166) or efavirenz-based (n = 160) antiretroviral therapy in Tororo, Uganda. Pregnant women living with HIV were enrolled between 12-28 weeks of gestation. Plasma samples were evaluated for angiogenic biomarkers (angiopoietin-1, angiopoietin-2, vascular endothelial growth factor, soluble fms-like tyrosine kinase-1, placental growth factor, and soluble endoglin) by enzyme-linked immunosorbent assay between: 16-<20, 20-<24, 24-<28, 28-<32, 32-<36, 36-<37 weeks of gestation. The primary outcome was preterm birth. RESULTS: In all, 1115 plasma samples from 326 pregnant women and adolescents were evaluated. There were no differences in angiogenic factors according to antiretroviral therapy group (P > .05 for all). The incidence of adverse birth outcomes was 16.9% for spontaneous preterm births, 25.6% for small-for-gestational-age births, and 2.8% for stillbirth. We used linear mixed effect modelling to evaluate longitudinal changes in angiogenic factor concentrations between birth outcome groups adjusting for gestational age at venipuncture, maternal age, body mass index, gravidity, and the interaction between treatment arm and gestational age. Two angiogenic factors-soluble endoglin and placental growth factor-were associated with adverse birth outcomes. Significantly higher concentrations of soluble endoglin throughout gestation were found in study participants destined to deliver preterm [likelihood ratio test, χ2(1) = 12.28, P < .0005] and in those destined to have stillbirths [χ2(1) = 5.67, P < .02]. By contrast, significantly lower concentrations of placental growth factor throughout gestation were found in those destined to have small-for-gestational-age births [χ2(1) = 7.89, P < .005] and in those destined to have stillbirths [χ2(1) = 21.59, P < .0001]. CONCLUSION: An antiangiogenic state in the second or third trimester is associated with adverse birth outcomes, including stillbirth in women and adolescents living with HIV and receiving antiretroviral therapy.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Nascimento Prematuro/epidemiologia , Natimorto/epidemiologia , Adulto , Alcinos , Angiopoietina-1/sangue , Angiopoietina-2/sangue , Benzoxazinas/uso terapêutico , Biomarcadores/sangue , Ciclopropanos , Combinação de Medicamentos , Endoglina/sangue , Feminino , Infecções por HIV/sangue , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Lopinavir/uso terapêutico , Neovascularização Fisiológica , Fator de Crescimento Placentário/sangue , Gravidez , Complicações Infecciosas na Gravidez/sangue , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Nascimento Prematuro/sangue , Ritonavir/uso terapêutico , Uganda/epidemiologia , Fator A de Crescimento do Endotélio Vascular/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue
17.
J Acquir Immune Defic Syndr ; 74(3): 279-284, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27828878

RESUMO

BACKGROUND: Lifelong antiretroviral therapy (ART) is recommended for all HIV-infected pregnant women, but early studies suggest that women often drop out of care postpartum and data are limited on virologic outcomes. METHODS: We evaluated viral suppression (primary outcome) and retention in care up to 5 years after ART initiation among HIV-infected women who started lifelong ART during pregnancy, irrespective of CD4 count, in a study in rural Uganda (NCT00993031). Participants were followed in the study for up to 1 year postpartum, then referred to clinics in surrounding communities. A random sample (N = 200) was invited to participate in a cross-sectional follow-up study after completing the trial, involving one visit for a questionnaire and pregnancy and HIV-1 RNA testing. Retention in care was defined as having attended an HIV clinic in the last 90 days. Logistic regression models were used to examine factors associated with viral suppression (HIV-1 RNA <400 copies/ml) at follow-up. RESULTS: One hundred fifty women (75%) were successfully contacted for follow-up at a median of 4.2 years after starting ART; 135 were retained in care [90%, 95% confidence interval (CI): 84.0% to 94.3%] and 121 demonstrated viral suppression (80.7%, 95% CI: 73.4% to 86.7%). Women who had disclosed their HIV status to their primary partner had greater odds of viral suppression (adjusted odds ratio: 4.51, 95% CI: 1.02 to 19.8). CONCLUSIONS: High rates of viral suppression can be achieved up to 5 years after initiating ART during pregnancy among women retained in care. Interventions to facilitate disclosure may improve long-term outcomes among women who initiate ART during pregnancy under universal treatment.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adesão à Medicação , Complicações Infecciosas na Gravidez/tratamento farmacológico , Resposta Viral Sustentada , Adulto , Estudos Transversais , Feminino , Seguimentos , HIV-1/isolamento & purificação , Humanos , Gravidez , RNA Viral/sangue , População Rural , Inquéritos e Questionários , Resultado do Tratamento , Uganda
18.
Malar J ; 15(1): 437, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27566109

RESUMO

BACKGROUND: Indoor residual spraying of insecticide (IRS) is a key intervention for reducing the burden of malaria in Africa. However, data on the impact of IRS on malaria in pregnancy and birth outcomes is limited. METHODS: An observational study was conducted within a trial of intermittent preventive therapy during pregnancy in Tororo, Uganda. Women were enrolled at 12-20 weeks of gestation between June and October 2014, provided with insecticide-treated bed nets, and followed through delivery. From December 2014 to February 2015, carbamate-containing IRS was implemented in Tororo district for the first time. Exact spray dates were collected for each household. The exposure of interest was the proportion of time during a woman's pregnancy under protection of IRS, with three categories of protection defined: no IRS protection, >0-20 % IRS protection, and 20-43 % IRS protection. Outcomes assessed included malaria incidence and parasite prevalence during pregnancy, placental malaria, low birth weight (LBW), pre-term delivery, and fetal/neonatal deaths. RESULTS: Of 289 women followed, 134 had no IRS protection during pregnancy, 90 had >0-20 % IRS protection, and 65 had >20-43 % protection. During pregnancy, malaria incidence (0.49 vs 0.10 episodes ppy, P = 0.02) and parasite prevalence (20.0 vs 8.9 %, P < 0.001) were both significantly lower after IRS. At the time of delivery, the prevalence of placental parasitaemia was significantly higher in women with no IRS protection (16.8 %) compared to women with 0-20 % (1.1 %, P = 0.001) or >20-43 % IRS protection (1.6 %, P = 0.006). Compared to women with no IRS protection, those with >20-43 % IRS protection had a lower risk of LBW (20.9 vs 3.1 %, P = 0.002), pre-term birth (17.2 vs 1.5 %, P = 0.006), and fetal/neonatal deaths (7.5 vs 0 %, P = 0.03). CONCLUSION: In this setting, IRS was temporally associated with lower malaria parasite prevalence during pregnancy and at delivery, and improved birth outcomes. IRS may represent an important tool for combating malaria in pregnancy and for improving birth outcomes in malaria-endemic settings. Trial Registration Current Controlled Trials Identifier NCT02163447.


Assuntos
Malária/epidemiologia , Malária/prevenção & controle , Controle de Mosquitos/métodos , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/prevenção & controle , Adulto , África , Animais , Antimaláricos/administração & dosagem , Quimioprevenção/métodos , Feminino , Humanos , Mosquiteiros Tratados com Inseticida , Malária/complicações , Gravidez , Resultado do Tratamento , Uganda/epidemiologia , Adulto Jovem
19.
N Engl J Med ; 374(10): 928-39, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26962728

RESUMO

BACKGROUND: Intermittent treatment with sulfadoxine-pyrimethamine is widely recommended for the prevention of malaria in pregnant women in Africa. However, with the spread of resistance to sulfadoxine-pyrimethamine, new interventions are needed. METHODS: We conducted a double-blind, randomized, controlled trial involving 300 human immunodeficiency virus (HIV)-uninfected pregnant adolescents or women in Uganda, where sulfadoxine-pyrimethamine resistance is widespread. We randomly assigned participants to a sulfadoxine-pyrimethamine regimen (106 participants), a three-dose dihydroartemisinin-piperaquine regimen (94 participants), or a monthly dihydroartemisinin-piperaquine regimen (100 participants). The primary outcome was the prevalence of histopathologically confirmed placental malaria. RESULTS: The prevalence of histopathologically confirmed placental malaria was significantly higher in the sulfadoxine-pyrimethamine group (50.0%) than in the three-dose dihydroartemisinin-piperaquine group (34.1%, P=0.03) or the monthly dihydroartemisinin-piperaquine group (27.1%, P=0.001). The prevalence of a composite adverse birth outcome was lower in the monthly dihydroartemisinin-piperaquine group (9.2%) than in the sulfadoxine-pyrimethamine group (18.6%, P=0.05) or the three-dose dihydroartemisinin-piperaquine group (21.3%, P=0.02). During pregnancy, the incidence of symptomatic malaria was significantly higher in the sulfadoxine-pyrimethamine group (41 episodes over 43.0 person-years at risk) than in the three-dose dihydroartemisinin-piperaquine group (12 episodes over 38.2 person-years at risk, P=0.001) or the monthly dihydroartemisinin-piperaquine group (0 episodes over 42.3 person-years at risk, P<0.001), as was the prevalence of parasitemia (40.5% in the sulfadoxine-pyrimethamine group vs. 16.6% in the three-dose dihydroartemisinin-piperaquine group [P<0.001] and 5.2% in the monthly dihydroartemisinin-piperaquine group [P<0.001]). In each treatment group, the risk of vomiting after administration of any dose of the study agents was less than 0.4%, and there were no significant differences among the groups in the risk of adverse events. CONCLUSIONS: The burden of malaria in pregnancy was significantly lower among adolescent girls or women who received intermittent preventive treatment with dihydroartemisinin-piperaquine than among those who received sulfadoxine-pyrimethamine, and monthly treatment with dihydroartemisinin-piperaquine was superior to three-dose dihydroartemisinin-piperaquine with regard to several outcomes. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT02163447.).


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/administração & dosagem , Malária/prevenção & controle , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/uso terapêutico , Quinolinas/administração & dosagem , Sulfadoxina/uso terapêutico , Adolescente , Adulto , Antimaláricos/efeitos adversos , Artemisininas/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Humanos , Incidência , Malária/epidemiologia , Parasitemia/epidemiologia , Gravidez , Resultado da Gravidez , Pirimetamina/efeitos adversos , Quinolinas/efeitos adversos , Sulfadoxina/efeitos adversos , Uganda , Vômito/induzido quimicamente , Adulto Jovem
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