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1.
J Infect Dis ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462671

RESUMO

BACKGROUND: The association between low-frequency HIV-1 drug resistance mutations (DRMs) and treatment failure (TF) is controversial. We explore this association using NGS methods that accurately sample low-frequency DRMs. METHODS: We enrolled women with HIV-1 in Malawi who were either ART naïve (A), had ART failure (B), or had discontinued ART (C). At entry, A and C began an NNRTI-based regimen and B started a PI-based regimen. We used Primer ID MiSeq to identify regimen-relevant DRMs in entry and TF plasma samples, and a Cox proportional hazards model to calculate hazard ratios (HRs) for entry DRMs. Low-frequency DRMs were defined as ≤ 20%. RESULTS: We sequenced 360 participants. Cohort B and C participants were more likely to have TF than Cohort A participants. The presence of K103N at entry significantly increased TF risk among A and C participants at both high and low frequency, with HR of 3.12 [1.58-6.18, 95% CI] and 2.38 [1.00-5.67, 95% CI] respectively. At TF, 45% of participants showed selection of DRMs while in the remaining participants there was an apparent lack of selective pressure from ART. CONCLUSIONS: Using accurate NGS for DRM detection may benefit an additional 10% of the patients by identifying low-frequency K103N mutations.

2.
AIDS ; 37(14): 2185-2190, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37877275

RESUMO

OBJECTIVE: The aim of this study was to understand how vaginal microbiota composition affects antiretroviral concentrations in the setting of hormonal contraception initiation. METHODS: Cervicovaginal fluid (CVF) concentrations of tenofovir, lamivudine, and efavirenz from 73 Malawian women with HIV were compared before and after initiation of depot-medroxyprogesterone acetate (DMPA) or levonorgestrel implant. We evaluated antiretroviral concentrations and vaginal microbiota composition/structure in the context of contraception initiation and predicted genital shedding using multivariable repeated measurements models fit by generalized estimating equations. RESULTS: Mean lamivudine CVF concentrations decreased 37% 1 month after contraception initiation. Subgroup analyses revealed a 41% decrease in women 1 month after initiating levonorgestrel implant, but no significant difference was observed in DMPA group alone. Tenofovir, lamivudine, and efavirenz CVF concentrations were positively correlated with anaerobic bacteria associated with nonoptimal vaginal microbiota. Risk of genital HIV shedding was not significantly associated with tenofovir or lamivudine CVF concentrations [tenofovir relative risk (RR): 0.098, P = 0.75; lamivudine RR: 0.142, P = 0.54]. Lack of association between genital HIV shedding and efavirenz CVF concentrations did not change when adjusting for vaginal microbiota composition and lamivudine/tenofovir CVF concentrations (RR: 1.33, P = 0.531). CONCLUSION: No effect of hormone initiation on genital shedding provides confidence that women with HIV on either DMPA or levonorgestrel implant contraception will not have compromised ART efficacy. The unexpected positive correlation between antiretroviral CVF concentrations and certain bacterial taxa relative abundance requires further work to understand the mechanism and clinical relevance.


Assuntos
Infecções por HIV , Microbiota , Feminino , Humanos , Levanogestrel , Lamivudina/uso terapêutico , Acetato de Medroxiprogesterona/uso terapêutico , Contracepção Hormonal , Malaui , Infecções por HIV/tratamento farmacológico , Vagina , Antirretrovirais/uso terapêutico , Tenofovir/uso terapêutico
3.
AIDS ; 37(14): 2233-2238, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37534689

RESUMO

OBJECTIVES: To examine the time required to suppress HIV in the genital tract with antiretroviral therapy (ART) in men with urethritis. DESIGN: An observational cohort study. METHODS: Men with HIV and urethritis not on ART were enrolled at an STI clinic in Malawi and offered to initiate ART. Blood and semen samples were collected pretreatment and at 1, 2, 4, 8, 12 and 24 weeks posturethritis treatment. Median viral loads (VLs) were calculated by ART initiation groups: 'within 1 week', 'between 1 and 4 weeks' and 'no ART before 4 weeks', based on the men's choice about whether or not to initiate ART. The presence of ART at each visit was confirmed by bioanalytical methods. FINDINGS: Between January 2017 and November 2018, 74 men presented with urethritis and HIV and were confirmed ART naive. The median age was 32 years. Forty-one (55% of men) initiated ART within 1 week; 12 (16%) between 1 and 4 weeks; and 21 (28%) did not initiate ART by week 4. Within the 1 week group, median VL was suppressed within 4 weeks in both semen and blood. Among the 1-4 weeks group, VL was suppressed within 4 weeks in semen and 5 weeks in blood. Among the no ART before 4 weeks group, VL in semen declined within the first 4 weeks but remained unsuppressed through week 24, and there was no significant decline in blood HIV. CONCLUSION: Treatment of urethritis and prompt initiation of ART with counseling for safer sex for at least one month is a critical measure to reduce transmission of HIV.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Uretrite , Masculino , Humanos , Adulto , Infecções por HIV/tratamento farmacológico , Sêmen , Uretrite/tratamento farmacológico , Estudos de Coortes , Carga Viral , Fármacos Anti-HIV/uso terapêutico
4.
mSphere ; 8(1): e0058522, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36622252

RESUMO

Important questions remain on how hormonal contraceptives alter the local immune environment and the microbiota in the female genital tract and how such effects may impact susceptibility to HIV infection. We leveraged samples from a previously conducted clinical trial of Malawian women with (n = 73) and without (n = 24) HIV infection randomized to depot medroxyprogesterone acetate (DMPA) or the levonogestrel implant in equal numbers within each group and determined the effects of these hormonal contraceptives (HCs) on the vaginal immune milieu and the composition of the vaginal microbiota. Longitudinal data for soluble immune mediators, measured by multiplex bead arrays and enzyme-linked immunosorbent assays (ELISAs), and vaginal microbiota, assessed by 16S rRNA gene amplicon, were collected prior to and over a period of 180 days post-HC initiation. DMPA and levonogestrel had only minimal effects on the vaginal immune milieu and microbiota. In women with HIV, with the caveat of a small sample size, there was an association between the median log10 change in the interleukin-12 (IL-12)/IL-10 ratio in vaginal fluid at day 180 post-HC compared to baseline when these women were classified as having a community state type (CST) IV vaginal microbiota and were randomized to DMPA. Long-lasting alterations in soluble immune markers or shifts in microbiota composition were not observed. Furthermore, women with HIV did not exhibit increased viral shedding in the genital tract after HC initiation. Consistent with the results of the ECHO (Evidence for Contraceptive Options and HIV Outcomes) trial, our data imply that the progestin-based HC DMPA and levonorgestrel are associated with minimal risk for women with HIV. (This study has been registered at ClinicalTrials.gov under registration no. NCT02103660). IMPORTANCE The results of the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial, the first large randomized controlled clinical trial comparing the HIV acquisition risk of women receiving DMPA, the levonorgestrel (LNG) implant, or the copper intrauterine device (IUD), did not reveal an increased risk of HIV acquisition for women on any of these three contraceptives. Our study results confirm that the two different progestin-based hormonal contraceptives DMPA and levonogestrel will not increase the risk for HIV infection. Furthermore, DMPA and levonogestrel have only minimal effects on the immune milieu and the microbiota in the vaginal tract, attesting to the safety of these hormonal contraceptives.


Assuntos
Contraceptivos Hormonais , Infecções por HIV , Microbiota , Feminino , Humanos , Anticoncepcionais/efeitos adversos , Anticoncepcionais/uso terapêutico , Citocinas/efeitos dos fármacos , Levanogestrel/efeitos adversos , Levanogestrel/uso terapêutico , Malaui , Acetato de Medroxiprogesterona/efeitos adversos , Acetato de Medroxiprogesterona/uso terapêutico , Microbiota/efeitos dos fármacos , Progestinas/farmacologia , RNA Ribossômico 16S , Contraceptivos Hormonais/efeitos adversos , Contraceptivos Hormonais/uso terapêutico
5.
JMIR Res Protoc ; 11(12): e37395, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36469400

RESUMO

BACKGROUND: Pre-exposure prophylaxis (PrEP) reduces HIV acquisition risk by >90% and is a critical lever to reduce HIV incidence. Identifying individuals most likely to benefit from PrEP and retaining them on PrEP throughout HIV risk is critical to realize PrEP's prevention potential. Individuals with sexually transmitted infections (STIs) are an obvious priority PrEP population, but there are no data from sub-Saharan Africa (SSA) confirming the effectiveness of integrating PrEP into STI clinics. Assisted partner notification may further enhance STI clinic-based PrEP programming by recruiting PrEP users from the pool of named sexual partners of individuals presenting with an incident STI. However, the acceptability, feasibility, and effectiveness of these integrated and enhanced strategies are unknown. OBJECTIVE: This study aims to describe the implementation outcomes of acceptability, feasibility, and effectiveness (regarding PrEP uptake and persistence) of integrating an enhanced PrEP implementation strategy into an STI clinic in Malawi. METHODS: The enhanced PrEP STI study is a prospective cohort study enrolling patients who are eligible for PrEP (aged ≥15 years) who are seeking STI services at a Lilongwe-based STI clinic. Data collection relies on a combination of in-depth interviews, patient and clinic staff surveys, and clinic record review. All enrolled PrEP users will be screened for acute HIV infection and receive quarterly testing for Neisseria gonorrhea, Chlamydia trachomatis, and syphilis. Participants will be asked to name recent sexual partners for assisted notification; returning partners will be screened for PrEP eligibility and, if interested, enrolled into the cohort of PrEP initiators. We will also enroll patients who are eligible for PrEP but choose not to initiate it, from the STI clinic. Patient participants will be followed for 6 months; we will assess self-reported PrEP use, PrEP refills, sexual behaviors, perceived HIV risk, and incident STIs. Clinic staff participants will be interviewed at baseline and at approximately 6 months and will complete surveys examining the perceived acceptability and feasibility of the integrated and enhanced PrEP strategy. RESULTS: Enrollment began in March 2022 and is projected to continue until February 2023, with patient participant follow-up through August 2023. The results of this study are expected to be reported in 2024. CONCLUSIONS: This study will generate important evidence regarding the potential integration of PrEP services into STI clinics in SSA and preliminary data regarding the effectiveness of an enhanced intervention that includes assisted partner notification as a strategy to identify potential PrEP users. Furthermore, this trial will provide some of the first insights into STI incidence among PrEP users recruited from an STI clinic in SSA-critical data to inform the use of etiologic STI testing where syndromic management is the current standard. These findings will help to design future PrEP implementation strategies in SSA. TRIAL REGISTRATION: ClinicalTrials.gov NCT05307991; https://clinicaltrials.gov/ct2/show/NCT05307991. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/37395.

6.
J Acquir Immune Defic Syndr ; 90(1): 56-61, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35044991

RESUMO

BACKGROUND: Persons with acute HIV infection (AHI) are highly infectious and responsible for a disproportionate share of incident infections. Immediate antiretroviral therapy (ART) rapidly reduces blood viral loads (VLs), but genital VLs after ART initiation during AHI are less well described. SETTING: Lilongwe, Malawi, 2012-2014. METHODS: HIV-seronegative and HIV-serodiscordant persons aged ≥18 years were screened for AHI (RNA positive) and randomized to standard of care, behavioral intervention, or behavioral intervention plus short-term ART (raltegravir/emtricitabine/tenofovir) (1:2:2). Persons who were ART eligible under Malawi guidelines could receive first-line therapy. Blood and genital VLs were assessed at weeks 1, 4, 8, and 12. Fisher's Exact test was used to compare viral suppression by ART status. RESULTS: Overall, 46 persons with AHI were enrolled; of whom, 17 started ART within 12 weeks. Median blood VL at AHI diagnosis was 836,115 copies/mL. At week 12, 7% (1/14) of those who initiated ART had a blood VL of ≥400 copies/mL, compared with 100% (23/23; P < 0.0001) of those who did not initiate ART (median VL: 61,605 copies/mL). Median genital VL at week 1 was 772 copies/mL, with 13 of 22 (59%) having VL of ≥400 copies/mL. At week 12, 0 of 10 (0%) of those who initiated ART had genital VL of ≥400 copies/mL, compared with 7 of 15 (47%) of those who did not initiate ART (P = 0.02). CONCLUSION: Although highly correlated, VLs in blood and genital fluids occupy discrete biological compartments with distinct virologic dynamics. Our results corroborate the dramatic reduction in both compartments after ART initiation. Increasing AHI screening and rapidly initiating treatment is key to interrupting transmission.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Genitália , Infecções por HIV/diagnóstico , Humanos , Malaui , Carga Viral
7.
J Infect Dis ; 225(2): 257-268, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34244739

RESUMO

BACKGROUND: Plasmodium falciparum malaria dominates throughout sub-Saharan Africa, but the prevalence of Plasmodium malariae, Plasmodium ovale spp., and Plasmodium vivax increasingly contribute to infection in countries that control malaria using P. falciparum-specific diagnostic and treatment strategies. METHODS: We performed quantitative polymerase chain reaction (qPCR) on 2987 dried blood spots from the 2015-2016 Malawi Demographic and Health Survey to identify presence and distribution of nonfalciparum infection. Bivariate models were used to determine species-specific associations with demographic and environmental risk factors. RESULTS: Nonfalciparum infections had broad spatial distributions. Weighted prevalence was 0.025 (SE, 0.004) for P. malariae, 0.097 (SE, 0.008) for P. ovale spp., and 0.001 (SE, 0.0005) for P. vivax. Most infections (85.6%) had low-density parasitemias ≤ 10 parasites/µL, and 66.7% of P. malariae, 34.6% of P. ovale spp., and 40.0% of P. vivax infections were coinfected with P. falciparum. Risk factors for P. malariae were like those known for P. falciparum; however, there were few risk factors recognized for P. ovale spp. and P. vivax, perhaps due to the potential for relapsing episodes. CONCLUSIONS: The prevalence of any nonfalciparum infection was 11.7%, with infections distributed across Malawi. Continued monitoring of Plasmodium spp. becomes critical as nonfalciparum infections become important sources of ongoing transmission.


Assuntos
Malária/epidemiologia , Plasmodium malariae/isolamento & purificação , Plasmodium ovale/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , Feminino , Humanos , Malária/diagnóstico , Malária Vivax/epidemiologia , Malaui/epidemiologia , Masculino , Plasmodium malariae/genética , Plasmodium ovale/genética , Plasmodium vivax/genética , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
8.
Int J Public Health ; 66: 629338, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335138

RESUMO

Objectives: Newborn screening in the United States and Europe allows early identification of congenital disorders but does not yet exist in most low-resource settings, especially in sub-Saharan Africa. Newborn screening can identify multiple inherited hematological disorders, but feasibility and effectiveness for Africa are not fully determined. Methods: Surplus dried blood spot collected in Central Malawi through the HIV Early Infant Diagnosis surveillance program were repurposed and tested by isoelectric focusing for sickle cell disease and trait. Additional genetic testing identified G6PD deficiency and alpha thalassemia. Results: Testing of 10,529 cards revealed an overall sickle cell trait prevalence of 7.0% (range 3.9-9.7% by district); 10 of 14 infants identified with sickle cell disease (prevalence 0.1%) were located and received care at a specialized clinic. Subsequent testing of 1,329 randomly selected cards identified alpha thalassemia trait in 45.7% of samples, and G6PD deficiency in 20.4% of males and 3.4% of females, with 29.0% of females as heterozygous carriers. Conclusion: Inherited hematological disorders are common in Central Malawi; early identification through newborn screening can improve clinical outcomes and should be supported throughout Africa.


Assuntos
Anemia Falciforme , Doenças Hematológicas , Triagem Neonatal , Anemia Falciforme/diagnóstico , Feminino , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Deficiência de Glucosefosfato Desidrogenase/genética , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/genética , Humanos , Recém-Nascido , Malaui/epidemiologia , Masculino , Estudos Prospectivos , Talassemia alfa/diagnóstico , Talassemia alfa/genética
10.
Microb Genom ; 7(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33295867

RESUMO

Antimicrobial resistance (AMR) is a global threat, including in sub-Saharan Africa. However, little is known about the genetics of resistant bacteria in the region. In Malawi, there is growing concern about increasing rates of antimicrobial resistance to most empirically used antimicrobials. The highly drug resistant Escherichia coli sequence type (ST) 131, which is associated with the extended spectrum ß-lactamase blaCTX-M-15, has been increasing in prevalence globally. Previous data from isolates collected between 2006 and 2013 in southern Malawi have revealed the presence of ST131 and the blaCTX-M-15 gene in the country. We performed whole genome sequencing (WGS) of 58 clinical E. coli isolates at Kamuzu Central Hospital, a tertiary care centre in central Malawi, collected from 2012 to 2018. We used Oxford Nanopore Technologies (ONT) sequencing, which was performed in Malawi. We show that ST131 is observed more often (14.9% increasing to 32.8%) and that the blaCTX-M-15 gene is occurring at a higher frequency (21.3% increasing to 44.8%). Phylogenetics indicates that isolates are highly related between the central and southern geographic regions and confirms that ST131 isolates are contained in a single group. All AMR genes, including blaCTX-M-15, were widely distributed across sequence types. We also identified an increased number of ST410 isolates, which in this study tend to carry a plasmid-located copy of blaCTX-M-15 gene at a higher frequency than blaCTX-M-15 occurs in ST131. This study confirms the expanding nature of ST131 and the wide distribution of the blaCTX-M-15 gene in Malawi. We also highlight the feasibility of conducting longitudinal genomic epidemiology studies of important bacteria with the sequencing done on site using a nanopore platform that requires minimal infrastructure.


Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli/epidemiologia , Escherichia coli/classificação , Sequenciamento Completo do Genoma/métodos , Adulto , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Estudos de Viabilidade , Feminino , Humanos , Estudos Longitudinais , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Filogenia , Plasmídeos/genética , Prevalência , Análise de Sequência de DNA , Centros de Atenção Terciária , Adulto Jovem
11.
Clin Infect Dis ; 73(7): e2000-e2004, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33033831

RESUMO

BACKGROUND: Prior to the widespread availability of antiretroviral therapy (ART), men living with human immunodeficiency virus (HIV) with urethritis had increased concentrations of HIV in semen. This study aims to better evaluate HIV shedding in men with urethritis receiving ART, and its implications for the cure of HIV. METHODS: Men living with HIV with urethritis taking ART ≥12 weeks were enrolled at a sexually transmitted infections clinic in Lilongwe, Malawi. Study follow-up included visits at 1, 2, 4, 8, 12, 24, 36, and 48 weeks after urethritis diagnosis and treatment. Matched blood and semen samples were collected at all visits, and all additional episodes of urethritis were followed with extra visits 1, 2, and 4 weeks after treatment. RESULTS: There were 111 men enrolled in the study between January 2017-March 2019, and 77 (69%) were suppressed in the blood (<400 copies/mL). Among the 77 men, 87 episodes of urethritis were evaluated during follow-up. Of the 87 episodes, 15 episodes (17%) had instances of seminal viral shedding ≥400 copies/mL despite viral suppression in the blood. During nonurethritis follow-up, ≤6% of men at each visit had a viral load ≥400 copies/mL in the semen while maintaining viral suppression in the blood. CONCLUSIONS: An HIV cure requires the elimination of HIV from every body compartment, but available ART does not currently accomplish this. Our study highlights the male genital tract as a local source of HIV that can be reversibly activated. A better understanding of this phenomenon is important to advance the HIV cure field.


Assuntos
Infecções por HIV , HIV-1 , Uretrite , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Masculino , RNA Viral , Sêmen , Uretrite/tratamento farmacológico , Carga Viral , Eliminação de Partículas Virais
12.
Contracept X ; 2: 100027, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33364598

RESUMO

OBJECTIVES: Our primary objective was to compare geometric mean levonorgestrel concentrations between levonorgestrel implant users who were or were not taking the antiretroviral efavirenz, for up to 30 months after implant initiation. Our secondary objective was to evaluate the pregnancy rate among levonorgestrel implant users on efavirenz. STUDY DESIGN: We performed a subanalysis of 42 Malawian women randomized to initiate the levonorgestrel implant as part of a parent randomized clinical trial. Our subset included 30 HIV-infected women taking efavirenz and 12 HIV-uninfected women not taking efavirenz. They underwent urine pregnancy testing every 3 months and serum levonorgestrel testing at day 3 and months 1, 3, 6, 12, 18, 24, 27 and 30 after implant initiation. Geometric mean levonorgestrel concentrations were calculated for efavirenz users and non-efavirenz users at each time point. RESULTS: The geometric mean levonorgestrel concentrations were lower for efavirenz users than non-efavirenz users at every time point; the geometric mean ratio for efavirenz users:non-efavirenz users ranged from 0.60 [90% confidence interval (CI) 0.46-0.79] at 1 month to 0.27 (90% CI 0.12-0.61) at 30 months after implant insertion. No pregnancies occurred over 60 woman-years of concomitant levonorgestrel implant and efavirenz use, although 11 women had levonorgestrel concentrations < 180 pg/mL (the previously suggested minimum threshold concentration for efficacy). CONCLUSIONS: Efavirenz users had lower levonorgestrel concentrations than non-efavirenz users, and one third of our concomitant efavirenz and levonorgestrel implant users had concentrations < 180 pg/mL. Continued evaluation of the contraceptive efficacy of the levonorgestrel implant may be needed for efavirenz users. IMPLICATIONS: Among 42 Malawian women using the levonorgestrel implant for contraception, women who were taking the antiretroviral efavirenz had lower serum levonorgestrel concentrations than women who were not taking efavirenz. However, none of the women who were taking efavirenz became pregnant over 60 women-years of follow-up.

13.
Sci Rep ; 10(1): 18740, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127922

RESUMO

Malaria remains a significant cause of morbidity and mortality in Malawi, with an estimated 18-19% prevalence of Plasmodium falciparum in children 2-10 years in 2015-2016. While children report the highest rates of clinical disease, adults are thought to be an important reservoir to sustained transmission due to persistent asymptomatic infection. The 2015-2016 Malawi Demographic and Health Survey was a nationally representative household survey which collected dried blood spots from 15,125 asymptomatic individuals ages 15-54 between October 2015 and February 2016. We performed quantitative polymerase chain reaction on 7,393 samples, detecting an overall P. falciparum prevalence of 31.1% (SE = 1.1). Most infections (55.6%) had parasitemias ≤ 10 parasites/µL. While 66.2% of individuals lived in a household that owned a bed net, only 36.6% reported sleeping under a long-lasting insecticide-treated net (LLIN) the previous night. Protective factors included urbanicity, greater wealth, higher education, and lower environmental temperatures. Living in a household with a bed net (prevalence difference 0.02, 95% CI - 0.02 to 0.05) and sleeping under an LLIN (0.01; - 0.02 to 0.04) were not protective against infection. Our findings demonstrate a higher parasite prevalence in adults than published estimates among children. Understanding the prevalence and distribution of asymptomatic infection is essential for targeted interventions.


Assuntos
Malária Falciparum/epidemiologia , Plasmodium falciparum/patogenicidade , Adolescente , Adulto , Feminino , Humanos , Mosquiteiros Tratados com Inseticida , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Temperatura , Adulto Jovem
14.
BMC Public Health ; 20(1): 910, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532234

RESUMO

BACKGROUND: RTS,S/AS01 is the first vaccine against malaria to undergo pilot implementation, beginning in 2019 and vaccinating 360,000 children per year in Malawi, Ghana, and Kenya. The four-dose vaccine is given as a primary three-dose series with a fourth dose given approximately 18 months later. The efficacy of RTS,S/AS01 was variable among the 11 sites participating in the 2009-2014 phase III trial (MALARIA-055, NCT00866619), possibly due to differences in transmission intensity. However, a within-site examination of environmental factors related to transmission intensity and their impact on vaccine efficacy has yet to be conducted. METHODS: We implemented the phase III RTS,S/AS01 trial at the Malawi site, which enrolled 1578 infants (6-12 weeks) and children (5-17 months) living in the Lilongwe District in Central Malawi and followed them for 3 years between 2009 and 2014. A global positioning system survey and an ecological questionnaire were conducted to collect participant household locations and characteristics, while additional data on background malaria prevalence were obtained from a concurrent Malaria Transmission Intensity (MTI) survey. Negative binomial regression models were used to assess whether the efficacy of the vaccine varied by estimated background malaria prevalence, household roof type, or amount of nearby vegetation. RESULTS: Vaccine efficacy did not significantly vary by estimated malaria prevalence or by roof type. However, increased vegetation cover was associated with an increase in the efficacy of the three-dose primary RTS,S/AS01 series in the 18 months before the fourth dose and a decrease in the efficacy of the primary vaccine series in the second 18 months following, if the fourth dose was not given. Vegetation cover did not alter the efficacy of the fourth dose in a statistically or practically significant manner. CONCLUSIONS: Vegetation coverage in this study site might be a proxy for nearness to rivers or branching, shallow wetlands called "dambos" which could serve as breeding sites for mosquitoes. We observed statistically significant modification of the efficacy of RTS,S/AS01 by forest cover, suggesting that initial vaccine efficacy and the importance of the fourth dose varies based on ecological context. TRIAL REGISTRATION: Efficacy of GSK Biologicals' Candidate Malaria Vaccine (257049) Against Malaria Disease Caused by P. falciparum Infection in Infants and Children in Africa. NCT00866619 prospectively registered 20 March 2009.


Assuntos
Vacinas Antimaláricas/imunologia , Malária Falciparum/epidemiologia , Plasmodium falciparum/imunologia , Criança , Meio Ambiente , Feminino , Sistemas de Informação Geográfica , Humanos , Lactente , Malária Falciparum/prevenção & controle , Malaui/epidemiologia , Masculino , Análise Espacial , Inquéritos e Questionários , Vacinação
15.
AIDS Res Hum Retroviruses ; 36(8): 641-646, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32390454

RESUMO

Overlap in metabolism pathways of endogenous female sex hormones and antiretroviral drugs may lead to altered exposure to these compounds. In a family planning clinic in Lilongwe, Malawi, blood, blood cell, and cervicovaginal fluid (CVF) samples from seventy-three HIV positive Malawian women taken in follicular and luteal menstrual phases were assessed for estradiol and progesterone by chemiluminescent immunoassay, and for antiretroviral concentration by liquid chromatography-mass spectrometry. In both follicular and luteal phases, estradiol concentrations were lower in women receiving efavirenz compared with women on non-efavirenz regimens or no antiretroviral therapy (p < .01). Serum estradiol was moderately and negatively correlated with efavirenz plasma (r = -0.36, p < .001) and CVF (r = -0.50, p < .001) concentrations. Serum estradiol was a significant predictor of efavirenz CVF concentrations even after adjusting for efavirenz plasma concentrations (p = .02). In upper-layer packed cells (ULPCs), tenofovir diphosphate (TFVdp) concentrations were similar between follicular and luteal phases and were not correlated with estradiol or progesterone concentrations. Tenofovir concentrations in CVF were not associated with menstrual cycle or serum hormone concentrations. In CVF and plasma, efavirenz concentrations were negatively correlated with serum estradiol concentrations, suggesting a modulatory effect of estradiol on efavirenz metabolism and/or transport processes, and/or an effect of efavirenz on the metabolism of estradiol. Differences in CVF persisted even after adjusting for plasma concentrations, suggesting a mechanism specific to the female genital compartment separate from absorption or hepatic metabolism. In contrast, TFVdp concentrations in ULPC were not influenced by endogenous estradiol or progesterone concentrations.


Assuntos
Antirretrovirais/sangue , Infecções por HIV/tratamento farmacológico , Progesterona/sangue , Vagina/química , Adolescente , Adulto , Antirretrovirais/classificação , Antirretrovirais/uso terapêutico , Líquidos Corporais/química , Colo do Útero/química , Feminino , Fase Folicular , Infecções por HIV/epidemiologia , Humanos , Fase Luteal , Malaui/epidemiologia , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
16.
Vaccine ; 38(25): 4079-4087, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32362527

RESUMO

BACKGROUND: RTS,S/AS01, the most advanced vaccine against malaria, is now undergoing pilot implementation in Malawi, Ghana, and Kenya where an estimated 360,000 children will be vaccinated each year. In this study we evaluate RTS,S/AS01 alongside bed net use and estimate cost-effectiveness. METHODS: RTS,S/AS01 phase III trial and bed net prevalence data were used to determine the effect of vaccination in the urban/periurban and rural areas of Lilongwe, Malawi. Cost data were used to calculate the cost-effectiveness of various interventions over three years. FINDINGS: Since bed nets reduce malaria incidence and homogeneous vaccine efficacy was assumed, participants without bed nets received greater relative benefit from vaccination with RTS,S/AS01 than participants with bed nets. Similarly, since malaria incidence in rural Lilongwe is higher than in urban Lilongwe, the impact and cost-effectiveness of vaccine interventions is increased in rural areas. In rural Lilongwe, we estimated that vaccinating one child without a bed net would prevent 2·59 (1·62 to 3·38) cases of malaria over three years, corresponding to a cost of $10·08 (7·71 to 16·13) per case averted. Alternatively, vaccinating one child with a bed net would prevent 1·59 (0·87 to 2·57) cases, corresponding to $16·43 (10·16 to 30·06) per case averted. Providing RTS,S/AS01 to 30,000 children in rural Lilongwe was estimated to cost $782,400 and to prevent 58,611 (35,778 to 82,932) cases of malaria over a three-year period. Joint interventions providing both vaccination and bed nets (to those without them) were estimated to prevent additional cases of malaria and to be similarly cost-effective, compared to vaccine-only interventions. INTERPRETATION: To maximize malaria prevention, vaccination and bed net distribution programs could be integrated. FUNDING: Impacts of Environment, Host Genetics and Antigen Diversity on Malaria Vaccine Efficacy (1R01AI137410-01).


Assuntos
Vacinas Antimaláricas , Malária Falciparum , Criança , Análise Custo-Benefício , Gana , Humanos , Lactente , Quênia/epidemiologia , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malaui/epidemiologia
17.
J Virol ; 94(12)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32269129

RESUMO

Concurrent sexually transmitted infections (STI) can increase the probability of HIV-1 transmission primarily by increasing the viral load present in semen. In this study, we explored the relationship of HIV-1 in blood and seminal plasma in the presence and absence of urethritis and after treatment of the concurrent STI. Primer ID deep sequencing of the V1/V3 region of the HIV-1 env gene was done for paired blood and semen samples from antiretroviral therapy (ART)-naive men living in Malawi with (n = 19) and without (n = 5) STI-associated urethritis; for a subset of samples, full-length env genes were generated for sequence analysis and to test entry phenotype. Cytokine concentrations in the blood and semen were also measured, and a reduction in the levels of proinflammatory cytokines was observed following STI treatment. We observed no difference in the prevalence of diverse compartmentalized semen-derived lineages in men with or without STI-associated urethritis, and these viral populations were largely stable during STI treatment. Clonal amplification of one or a few viral sequences accounted for nearly 50% of the viral population, indicating a recent bottleneck followed by limited viral replication. We conclude that the male genital tract is a site where virus can be brought in from the blood, where localized sustained replication can occur, and where specific genotypes can be amplified, perhaps initially by cellular proliferation but further by limited viral replication.IMPORTANCE HIV-1 infection is a sexually transmitted infection that coexists with other STI. Here, we examined the impact of a concurrent STI resulting in urethritis on the HIV-1 population within the male genital tract. We found that viral populations remain largely stable even with treatment of the STI. These results show that viral populations within the male genital tract are defined by factors beyond transient inflammation associated with a concurrent STI.


Assuntos
Infecções por HIV/virologia , HIV-1/genética , Sêmen/virologia , Infecções Sexualmente Transmissíveis/virologia , Uretrite/virologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Adulto , Sequência de Bases , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Estudos de Coortes , Citocinas/genética , Citocinas/imunologia , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , Infecções por HIV/transmissão , HIV-1/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Filogenia , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/imunologia , Infecções Sexualmente Transmissíveis/transmissão , Uretrite/epidemiologia , Replicação Viral , Produtos do Gene env do Vírus da Imunodeficiência Humana/sangue , Produtos do Gene env do Vírus da Imunodeficiência Humana/classificação
18.
Gates Open Res ; 4: 139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33447735

RESUMO

Conducting collaborative and comprehensive epidemiological research on neonatal sepsis in low- and middle-income countries (LMICs) is challenging due to a lack of diagnostic tests. This prospective study protocol aims to obtain epidemiological data on bacterial sepsis in newborns and young infants at Kamuzu Central Hospital in Lilongwe, Malawi. The main goal is to determine if the use of whole blood transcriptome host immune response signatures can help in the identification of infants who have sepsis of bacterial causes. The protocol includes a detailed clinical assessment with vital sign measurements, strict aseptic blood culture protocol with state-of-the-art microbial analyses and RNA-sequencing and metagenomics evaluations of host responses and pathogens, respectively. We also discuss the directions of a brief analysis plan for RNA sequencing data. This study will provide robust epidemiological data for sepsis in neonates and young infants in a setting where sepsis confers an inordinate burden of disease.

19.
Pediatr Blood Cancer ; 66(11): e27954, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31397075

RESUMO

INTRODUCTION: Sickle cell disease (SCD) is among the most common inherited hematologic diseases in sub-Saharan Africa (SSA). Historically, hydroxyurea administration in SSA has been restricted due to limited region-specific evidence for safety and efficacy. METHODS: We conducted a prospective observational cohort study of pediatric patients with SCD in Malawi. From January 2015 to November 2017, hydroxyurea at doses of 10-20 mg/kg/day was administered to children with clinically severe disease (targeted use policy). From December 2017 to July 2018, hydroxyurea was prescribed to all patients (universal use policy). RESULTS: Of 187 patients with SCD, seven (3.7%) died and 23 (12.3%) were lost to follow-up. The majority (135, 72.2%) were prescribed hydroxyurea, 59 (43.7%) under the targeted use policy and 76 (56.3%) under the universal use policy. There were no documented severe toxicities. Under the targeted use policy, children with SCD demonstrated absolute decreases in the rates of hospitalization (-4.1 per 1000 person-days; -7.2, -1.0; P = .004), fevers (-4.2 per 1000 person-days; -7.2, -1.1; P = .002), transfusions (-2.3 per 1000 person-days; 95% confidence interval: -4.9, 0.3; P = .06), and annual school absenteeism (-51.2 per person-year; -60.1, -42.3; P < .0001) within 6 months of hydroxyurea commencement. CONCLUSION: We successfully implemented universal administration of hydroxyurea to children with SCD at a tertiary hospital in Malawi. Similar to recently reported trials, hydroxyurea was safe and effective during routine programmatic experience, with clinical benefits particularly among high-risk children. This highlights the importance of continued widespread scale-up of hydroxyurea within SCD programs across SSA.


Assuntos
Anemia Falciforme/tratamento farmacológico , Países em Desenvolvimento , Hidroxiureia/uso terapêutico , Absenteísmo , Adolescente , Anemia Falciforme/epidemiologia , Transfusão de Sangue/estatística & dados numéricos , Criança , Pré-Escolar , Terapia Combinada , Feminino , Febre/epidemiologia , Febre/etiologia , Hemoglobinas/análise , Hospitalização/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Humanos , Hidroxiureia/efeitos adversos , Hidroxiureia/provisão & distribuição , Lactente , Cooperação Internacional , Malaui/epidemiologia , Masculino , North Carolina , Pacientes Desistentes do Tratamento , Utilização de Procedimentos e Técnicas , Estudos Prospectivos , Centros de Atenção Terciária/estatística & dados numéricos
20.
Contraception ; 100(5): 402-405, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31374188

RESUMO

OBJECTIVE: To compare medroxyprogesterone acetate (MPA) concentrations between HIV-positive women on antiretroviral therapy (ART) and HIV-negative women initiating depot medroxyprogesterone (DMPA) injectable. STUDY DESIGN: Secondary analysis of 28 HIV-positive women on non-nucleoside reverse transcriptase inhibitor-containing ART regimens and 10 HIV-negative women randomized to initiate DMPA in a clinical trial of progestin contraception in Malawi. RESULTS: MPA concentrations were significantly lower among HIV-positive women on ART, compared with HIV-negative women, at week 4 and week 13 (p=.03 for both), but not at day 3 or week 26 post-DMPA initiation. CONCLUSIONS: Antiretroviral medications may affect MPA metabolism in HIV-positive African women.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Anticoncepcionais Femininos/farmacocinética , Infecções por HIV/tratamento farmacológico , Acetato de Medroxiprogesterona/farmacocinética , Progestinas/uso terapêutico , Adulto , Anticoncepção/métodos , Anticoncepcionais Femininos/uso terapêutico , Preparações de Ação Retardada , Feminino , Humanos , Malaui , Acetato de Medroxiprogesterona/uso terapêutico , Resultado do Tratamento , Adulto Jovem
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