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1.
BMC Health Serv Res ; 24(1): 597, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715044

RESUMO

BACKGROUND: Globally, a fifth of the children continue to face chronic undernutrition with a majority of them situated in the Low- and Middle-Income Countries (LMIC). The rising numbers are attributed to aggravating factors like limited nutrition knowledge, poor feeding practices, seasonal food insecurity, and diseases. Interventions targeting behaviour change may reduce the devastating nutrition situation of children in the LMICs. OBJECTIVE: For the co-design of a Behaviour Change Communication (BCC) intervention for young children in rural Kenya, we aimed to identify the experiences, barriers, facilitators, and preferences of caregivers and stakeholders regarding nutrition and health counselling. DESIGN: We employed a qualitative study design and used a semi-structured interview guide. The in-depth interviews were recorded, transcribed, and analysed using content analysis, facilitated by the software NVivo. SETTING: Health and Demographic Surveillance System (HDSS) area in Siaya County, rural Kenya. PARTICIPANTS: We interviewed 30 caregivers of children between 6 and 23 months of age and 29 local stakeholders with experience in implementing nutrition projects in Kenya. RESULTS: Nutrition and health counselling (NHC) was usually conducted in hospital settings with groups of mothers. Barriers to counselling were long queues and delays, long distances and high travel costs, the inapplicability of the counselling content, lack of spousal support, and a high domestic workload. Facilitators included the trust of caregivers in Community Health Volunteers (CHVs) and counselling services offered free of charge. Preferences comprised (1) delivering of counselling by CHVs, (2) offering individual and group counselling, (3) targeting male and female caregivers. CONCLUSION: There is a disconnect between the caregivers' preferences and the services currently offered. Among these families, a successful BCC strategy that employs nutrition and health counselling should apply a community-based communication channel through trusted CHVs, addressing male and female caregivers, and comprising group and individual sessions.


Assuntos
Cuidadores , Aconselhamento , Pesquisa Qualitativa , População Rural , Humanos , Quênia , Cuidadores/psicologia , Aconselhamento/métodos , Lactente , Feminino , Masculino , Adulto , Entrevistas como Assunto
2.
Open Forum Infect Dis ; 11(Suppl 1): S91-S100, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532953

RESUMO

Background: Although Shigella is an important cause of diarrhea in Kenyan children, robust research platforms capable of conducting incidence-based Shigella estimates and eventual Shigella-targeted clinical trials are needed to improve Shigella-related outcomes in children. Here, we describe characteristics of a disease surveillance platform whose goal is to support incidence and consequences of Shigella diarrhea as part of multicounty surveillance aimed at preparing sites and assembling expertise for future Shigella vaccine trials. Methods: We mobilized our preexisting expertise in shigellosis, vaccinology, and diarrheal disease epidemiology, which we combined with our experience conducting population-based sampling, clinical trials with high (97%-98%) retention rates, and healthcare utilization surveys. We leveraged our established demographic surveillance system (DSS), our network of healthcare centers serving the DSS, and our laboratory facilities with staff experienced in performing microbiologic and molecular diagnostics to identify enteric infections. We joined these resources with an international network of sites with similar capabilities and infrastructure to form a cohesive scientific network, designated Enterics for Global Health (EFGH), with the aim of expanding and updating our knowledge of the epidemiology and adverse consequences of shigellosis and enriching local research and career development priorities. Conclusions: Shigella surveillance data from this platform could help inform Shigella vaccine trials.

3.
Am J Trop Med Hyg ; 110(4): 677-680, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38460198

RESUMO

Unlike praziquantel, artemisinin derivatives are effective against juvenile schistosome worms. We assessed the efficacy and safety of a single oral dose of artesunate plus sulfalene-pyrimethamine versus praziquantel in the treatment of Schistosoma mansoni. Seventy-three schoolchildren (aged 9-15 years) with confirmed S. mansoni infection in Rarieda, western Kenya, were randomly assigned to receive either a single oral dose of artesunate plus sulfalene-pyrimethamine (n = 39) or a single dose of praziquantel (n = 34). The cure and egg reduction rates at 4 weeks posttreatment were 69.4% (25/36) versus 80.6% (25/31) (P = 0.297) and 99.1% versus 97.5% (P = 0.607) in the artesunate plus sulfalene-pyrimethamine group versus praziquantel group, respectively. Fourteen children developed adverse events, and there were no serious adverse events. A single oral dose of artesunate plus sulfalene-pyrimethamine has efficacy comparable to that of praziquantel in the treatment of S. mansoni, but these results should be confirmed in larger randomized controlled trials.


Assuntos
Anti-Helmínticos , Artemisininas , Esquistossomose mansoni , Sulfaleno , Criança , Animais , Humanos , Praziquantel/efeitos adversos , Artesunato/uso terapêutico , Schistosoma mansoni , Quênia , Sulfaleno/farmacologia , Sulfaleno/uso terapêutico , Pirimetamina/uso terapêutico , Artemisininas/efeitos adversos , Quimioterapia Combinada , Esquistossomose mansoni/tratamento farmacológico , Resultado do Tratamento , Anti-Helmínticos/uso terapêutico
4.
Pan Afr Med J ; 46: 21, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107343

RESUMO

Introduction: as a public health policy, the ongoing global coronavirus disease 2019 vaccination drives require continuous tracking, tracing, and testing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Diagnostic testing is important in virus detection and understanding its spread for timely intervention. This is especially important for low-income settings where the majority of the population remains untested. This is well supported by the fact that of about 9% of the Kenyan population had been tested for the virus. Methods: this was a cross-sectional study conducted at the Kisumu and Siaya Referral Hospitals in Kenya. Here we report on the sensitivity and specificity of the rapid antigen detection test (Ag-RDT) of SARS-CoV-2 compared with the quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) using stool and nasopharyngeal swab samples. Further, the mean Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibody levels among symptomatic and asymptomatic individuals in western Kenya were evaluated. Results: the sensitivity and specificity of Ag-RDT were 76.3% (95% CI, 59.8-88.6%) and 96.3% (95% CI, 87.3-99.5%) with a negative and positive predictive value of 85% (95% CI, 73.8%-93.0%) and 93% (95% CI, 78.6%-99.2%) respectively. There was substantial agreement of 88% (Kappa value of 0.75, 95% CI, 0.74-0.77) between Ag-RDT and nasopharyngeal swab RT-qPCR, and between stool and nasopharyngeal swab RT-qPCR results (83.7% agreement, Kapa value 0.62, 95% CI 0.45-0.80). The mean IgM and IgG antibody response to SARS-CoV-2 were not different in asymptomatic individuals, 1.11 (95% CI, 0.78-1.44) and 0.88 (95% CI, 0.65-1.11) compared to symptomatic individuals 4.30 (95% CI 3.30-5.31) and 4.16 (95% CI 3.32 -5.00). Conclusion: the choice of an appropriate SARS-CoV-2 diagnostic, screening, and surveillance test should be guided by the specific study needs and a rational approach for optimal results.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Estudos Transversais , Quênia , Anticorpos Antivirais , Imunoglobulina M , Sensibilidade e Especificidade , Imunoglobulina G , Nasofaringe
5.
Trials ; 24(1): 763, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012787

RESUMO

BACKGROUND: Schistosomiasis control relies on praziquantel for preventive chemotherapy. Alternative drugs are needed for the treatment and control of schistosomiasis. Praziquantel is effective against adult schistosome worms but ineffective against larval stages of the parasite and cannot prevent re-infection or interrupt the transmission of infection. Continued reliance on praziquantel for wide-scale schistosomiasis control will likely accelerate the emergence of drug resistance. Artemisinin derivatives are effective against the juvenile stages but ineffective against adult worms. The SCHISTOACT study aimed to evaluate the efficacy and safety of praziquantel plus one of four artemisinin-based combinations in treating Schistosoma mansoni infection in Kenya. METHODS: The SCHISTOACT study is an open-label, head-to-head, five-arm, proof-of-concept, non-inferiority, individually randomized controlled trial with a follow-up of 12 weeks. A total of 540 primary school-aged children from the Mwea area, Kirinyaga County in central Kenya, diagnosed with S. mansoni infection (by Kato-Katz method) are randomly allocated (1:1:1:1:1) to a single dose of praziquantel plus a 3-day course of artesunate-sulfalene/pyrimethamine, or artesunate-amodiaquine, or artesunate plus mefloquine, or dihydroartemisinin-piperaquine, or praziquantel control arm. The primary endpoints are efficacy (cure rate, assessed by microscopy) and safety (adverse events) of each study arm 6 weeks after treatment. Secondary endpoints include cumulative cure rate, egg reduction rate, and re-infection 12 weeks after treatment. The non-inferiority margin is set at - 10 for the risk difference in cure rates between praziquantel and the combined treatment. DISCUSSION: This study assesses a strategy for repurposing artemisinin-based combination therapies (ACTs) for treating schistosomiasis. It adopts a head-to-head comparison of four different ACTs to test a non-inferiority hypothesis and to strengthen local capacity to conduct clinical trials for interventions against neglected tropical diseases. TRIAL REGISTRATION: Pan-African Clinical Trials Registry PACTR202001919442161 . Retrospectively registered on 6 January 2020.


Assuntos
Anti-Helmínticos , Artemisininas , Esquistossomose mansoni , Esquistossomose , Adulto , Animais , Criança , Humanos , Artemisininas/efeitos adversos , Artesunato/efeitos adversos , Quimioterapia Combinada , Praziquantel/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Reinfecção/induzido quimicamente , Reinfecção/tratamento farmacológico , Schistosoma mansoni , Esquistossomose/tratamento farmacológico , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/induzido quimicamente , Resultado do Tratamento , Estudos de Equivalência como Asunto
6.
Front Public Health ; 11: 1153559, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304117

RESUMO

Background: Climate change significantly impacts health in low-and middle-income countries (LMICs), exacerbating vulnerabilities. Comprehensive data for evidence-based research and decision-making is crucial but scarce. Health and Demographic Surveillance Sites (HDSSs) in Africa and Asia provide a robust infrastructure with longitudinal population cohort data, yet they lack climate-health specific data. Acquiring this information is essential for understanding the burden of climate-sensitive diseases on populations and guiding targeted policies and interventions in LMICs to enhance mitigation and adaptation capacities. Objective: The objective of this research is to develop and implement the Change and Health Evaluation and Response System (CHEERS) as a methodological framework, designed to facilitate the generation and ongoing monitoring of climate change and health-related data within existing Health and Demographic Surveillance Sites (HDSSs) and comparable research infrastructures. Methods: CHEERS uses a multi-tiered approach to assess health and environmental exposures at the individual, household, and community levels, utilizing digital tools such as wearable devices, indoor temperature and humidity measurements, remotely sensed satellite data, and 3D-printed weather stations. The CHEERS framework utilizes a graph database to efficiently manage and analyze diverse data types, leveraging graph algorithms to understand the complex interplay between health and environmental exposures. Results: The Nouna CHEERS site, established in 2022, has yielded significant preliminary findings. By using remotely-sensed data, the site has been able to predict crop yield at a household level in Nouna and explore the relationships between yield, socioeconomic factors, and health outcomes. The feasibility and acceptability of wearable technology have been confirmed in rural Burkina Faso for obtaining individual-level data, despite the presence of technical challenges. The use of wearables to study the impact of extreme weather on health has shown significant effects of heat exposure on sleep and daily activity, highlighting the urgent need for interventions to mitigate adverse health consequences. Conclusion: Implementing the CHEERS in research infrastructures can advance climate change and health research, as large and longitudinal datasets have been scarce for LMICs. This data can inform health priorities, guide resource allocation to address climate change and health exposures, and protect vulnerable communities in LMICs from these exposures.


Assuntos
Mudança Climática , Projetos de Pesquisa , Humanos , Atividades Cotidianas , África , Algoritmos
7.
BMC Vet Res ; 18(1): 363, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183113

RESUMO

BACKGROUND: It has been proposed that childhood vaccines in high-mortality populations may have substantial impacts on mortality rates that are not explained by the prevention of targeted diseases, nor conversely by typical expected adverse reactions to the vaccines, and that these non-specific effects (NSEs) are generally more pronounced in females. The existence of these effects, and any implications for the development of vaccines and the design of vaccination programs to enhance safety, remain controversial. One area of controversy is the reported association of non-live vaccines with increased female mortality. In a previous randomized controlled trial (RCT), we observed that non-live alum-adjuvanted animal rabies vaccine (ARV) was associated with increased female but not male mortality in young, free-roaming dogs. Conversely, non-live non-adjuvanted human rabies vaccine (NRV) has been associated with beneficial non-specific effects in children. Alum adjuvant has been shown to suppress Th1 responses to pathogens, leading us to hypothesize that alum-adjuvanted rabies vaccine in young dogs has a detrimental effect on female survival by modulating the immune response to infectious and/or parasitic diseases. In this paper, we present the protocol of a 3-arm RCT comparing the effect of alum-adjuvanted rabies vaccine, non-adjuvanted rabies vaccine and placebo on all-cause mortality in an owned, free-roaming dog population, with causal mediation analysis of the RCT and a nested case-control study to test this hypothesis. METHODS: Randomised controlled trial with a nested case-control study. DISCUSSION: We expect that, among the placebo group, males will have higher mortality caused by higher pathogen loads and more severe disease, as determined by haematological parameters and inflammatory biomarkers. Among females, we expect that there will be no difference in mortality between the NRV and placebo groups, but that the ARV group will have higher mortality, again mediated by higher pathogen loads and more severe disease. We anticipate that these changes are preceded by shifts in key serum cytokine concentrations towards an anti-inflammatory immune response in females. If confirmed, these results will provide a rational basis for mitigation of detrimental NSEs of non-live vaccines in high-mortality populations.


Assuntos
Doenças do Cão , Vacina Antirrábica , Raiva , Adjuvantes Imunológicos/farmacologia , Compostos de Alúmen , Animais , Anti-Inflamatórios , Biomarcadores , Estudos de Casos e Controles , Ensaios Clínicos Veterinários como Assunto , Citocinas , Doenças do Cão/epidemiologia , Doenças do Cão/prevenção & controle , Cães , Feminino , Humanos , Masculino , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária , Vacinação/veterinária
8.
Trials ; 23(1): 449, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650583

RESUMO

BACKGROUND: Climate change heavily affects child nutritional status in sub-Saharan Africa. Agricultural and dietary diversification are promising tools to balance agricultural yield losses and nutrient deficits in crops. However, rigorous impact evaluation of such adaptation strategies is lacking. This project will determine the potential of an integrated home gardening and nutrition counseling program as one possible climate change adaptation strategy to improve child health in rural Burkina Faso and Kenya. METHODS: Based on careful co-design with stakeholders and beneficiaries, we conduct a multi-center, cluster-randomized controlled trial with 2 × 600 households in North-Western Burkina Faso and in South-Eastern Kenya. We recruit households with children at the age of complementary feed introduction (6-24 months) and with access to water sources. The intervention comprises the bio-diversification of horticultural home gardens and nutritional health counseling, using the 7 Essential Nutrition Action messages by the World Health Organization. After 12-months of follow-up, we will determine the intervention effect on the primary health outcome height-for-age z-score, using multi-level mixed models in an intention-to-treat approach. Secondary outcomes comprise other anthropometric indices, iron and zinc status, dietary behavior, malaria indicators, and household socioeconomic status. DISCUSSION: This project will establish the potential of a home gardening and nutrition counseling program to counteract climate change-related quantitative and qualitative agricultural losses, thereby improving the nutritional status among young children in rural sub-Saharan Africa. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) DRKS00019076 . Registered on 27 July 2021.


Assuntos
Transtornos da Nutrição Infantil , Desnutrição , Burkina Faso , Criança , Transtornos da Nutrição Infantil/diagnóstico , Transtornos da Nutrição Infantil/prevenção & controle , Pré-Escolar , Aconselhamento , Jardinagem , Jardins , Humanos , Lactente , Quênia , Desnutrição/diagnóstico , Desnutrição/prevenção & controle , Estudos Multicêntricos como Assunto , Estado Nutricional , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
PLOS Glob Public Health ; 2(9): e0000951, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36962806

RESUMO

We investigated the first 152 laboratory-confirmed SARS-CoV-2 cases (125 primary and 27 secondary) and their 248 close contacts in Kisumu County, Kenya. Conducted June 10-October 8, 2020, this study included interviews and sample collection at enrolment and 14-21 days later. Median age was 35 years (IQR 28-44); 69.0% reported COVID-19 related symptoms, most commonly cough (60.0%), headache (55.2%), fever (53.3%) and loss of taste or smell (43.8%). One in five were hospitalized, 34.4% >25 years of age had at least one comorbidity, and all deaths had comorbidities. Adults ≥25 years with a comorbidity were 3.15 (95% CI 1.37-7.26) times more likely to have been hospitalized or died than participants without a comorbidity. Infectious comorbidities included HIV, tuberculosis, and malaria, but no current cases of influenza, respiratory syncytial virus, dengue fever, leptospirosis or chikungunya were identified. Thirteen (10.4%) of the 125 primary infections transmitted COVID-19 to 27 close contacts, 158 (63.7%) of whom resided or worked within the same household. Thirty-one percent (4 of 13) of those who transmitted COVID-19 to secondary cases were health care workers; no known secondary transmissions occurred between health care workers. This rapid assessment early in the course of the COVID-19 pandemic identified some context-specific characteristics which conflicted with the national line-listing of cases, and which have been substantiated in the year since. These included over two-thirds of cases reporting the development of symptoms during the two weeks after diagnosis, compared to the 7% of cases reported nationally; over half of cases reporting headaches, and nearly half of all cases reporting loss of taste and smell, none of which were reported at the time by the World Health Organization to be common symptoms. This study highlights the importance of rapid in-depth assessments of outbreaks in understanding the local epidemiology and response measures required.

11.
Front Microbiol ; 12: 734929, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690973

RESUMO

Most studies of HIV-1 transmission have focused on subtypes B and C. In this study, we determined the genomic sequences of the transmitted founder (TF) viruses from acutely infected individuals enrolled between 2005 and 2011 into IAVI protocol C in Rwanda and have compared these isolates to viruses from more recent (2016-2019) acute/early infections in three at risk populations - MSM, high risk women (HRW), and discordant couples (DC). For the Protocol C samples, we utilized near full-length single genome (NFLG) amplification to generate 288 HIV-1 amplicons from 26 acutely infected seroconverters (SC), while for the 21 recent seroconverter samples (13 from HRW, two from DC, and six from MSM), we PCR amplified overlapping half-genomes. Using PacBio SMRT technology combined with the MDPseq workflow, we performed multiplex sequencing to obtain high accuracy sequences for each amplicon. Phylogenetic analyses indicated that the majority of recent transmitted viruses from DC and HRW clustered within those of the earlier Protocol C cohort. However, five of six sequences from the MSM cohort branched together and were greater than 97% identical. Recombination analyses revealed a high frequency (6/26; 23%) of unique inter-subtype recombination in Protocol C with 19% AC and 4% CD recombinant viruses, which contrasted with only 6.5% of recombinants defined by sequencing of the pol gene previously. The frequency of recombinants was significantly higher (12/21; 57%) in the more recent isolates, although, the five related viruses from the MSM cohort had identical recombination break points. While major drug resistance mutations were absent from Protocol C viruses, 4/21 of recent isolates exhibited transmitted nevirapine resistance. These results demonstrate the ongoing evolution and increased prevalence of recombinant and drug resistant transmitted viruses in Rwanda and highlight the importance of defining NFLG sequences to fully understand the nature of TF viruses and in particular the prevalence of unique recombinant forms (URFs) in transmission cohorts.

12.
Front Immunol ; 12: 609884, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679745

RESUMO

Predictive models are becoming more and more commonplace as tools for candidate antigen discovery to meet the challenges of enabling epitope mapping of cohorts with diverse HLA properties. Here we build on the concept of using two key parameters, diversity metric of the HLA profile of individuals within a population and consideration of sequence diversity in the context of an individual's CD8 T-cell immune repertoire to assess the HIV proteome for defined regions of immunogenicity. Using this approach, analysis of HLA adaptation and functional immunogenicity data enabled the identification of regions within the proteome that offer significant conservation, HLA recognition within a population, low prevalence of HLA adaptation and demonstrated immunogenicity. We believe this unique and novel approach to vaccine design as a supplement to vitro functional assays, offers a bespoke pipeline for expedited and rational CD8 T-cell vaccine design for HIV and potentially other pathogens with the potential for both global and local coverage.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV/imunologia , Interações Hospedeiro-Patógeno/imunologia , Aprendizado de Máquina , Antígenos Virais/genética , Antígenos Virais/imunologia , Epitopos de Linfócito T/imunologia , Variação Genética , Genoma Viral , Antígenos HLA/imunologia , Humanos , Peptídeos/imunologia , Proteoma , Proteínas Virais
13.
PLoS Negl Trop Dis ; 12(8): e0006710, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089120

RESUMO

BACKGROUND: Among the different faces of immune reconstitution inflammatory syndrome (IRIS) developing in HIV-patients, no clinical definition has been reported for Schistosomiasis-IRIS (Schisto-IRIS). Although Schisto-IRIS remains largely uninvestigated, matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) have previously been associated with S. mansoni infection and tuberculosis-IRIS. Here, we aimed to investigate the relevance of these markers in Schisto-IRIS. METHODOLOGY: Patients were diagnosed with IRIS related to S. mansoni within a cohort of patients with Schistosomiasis-HIV co-infection, using a clinical working definition of Schisto-IRIS. We compared 9 patients who developed Schisto-IRIS to 9 Schisto+HIV+ controls who did not, and 9 Schisto-HIV+ controls. Plasma levels of MMP-1, MMP-7, MMP-10, TIMP-1, TIMP-2, sCD14, intestinal fatty-acid binding protein, C-reactive protein, and 8 anti-nuclear antibodies (ANA) were analyzed prior to and during 3 months of ART. PRINCIPAL FINDINGS: Although no differences were observed for MMP-1 and -7, MMP-10 levels decreased significantly in Schisto+HIV+ controls during 3 months of ART (p = 0.005) while persisting in Schisto-IRIS patients at significantly higher levels compared to Schisto-HIV+ controls (p≤0.030). In contrast TIMP-1 levels only decreased significantly in Schisto-IRIS patients (p = 0.012), while TIMP-2 levels were lower compared to Schisto+HIV+ controls at 2 weeks (p = 0.007), 1 month (p = 0.005) and 3 months (p = 0.031) of ART. Five out of 8 ANAs studied decreased significantly in Schisto-IRIS patients after 1 month of ART(p≤0.039), whereas only 1 ANA decreased for Schisto+HIV+ controls (p = 0.027). CONCLUSIONS/SIGNIFICANCE: In this study, we propose a working definition for the diagnosis of Schisto-IRIS in resource limited settings. We report persistent plasma levels of MMP-10, along with a more pronounced decrease in TIMP-1 and ANA-levels, and low levels of TIMP-2 during 3 months of ART. Corresponding to the clinical symptoms, these data suggest that Schisto-IRIS is marked by unbalanced MMP/TIMP dynamics which favor inflammation.


Assuntos
Síndrome Inflamatória da Reconstituição Imune/diagnóstico , Síndrome Inflamatória da Reconstituição Imune/etiologia , Metaloproteinases da Matriz/metabolismo , Esquistossomose mansoni/complicações , Inibidores Teciduais de Metaloproteinases/metabolismo , Adulto , Animais , Biomarcadores , Estudos de Casos e Controles , Estudos de Coortes , Coinfecção , Feminino , Infecções por HIV , Humanos , Quênia/epidemiologia , Masculino , Metaloproteinases da Matriz/sangue , Schistosoma mansoni , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/imunologia , Inibidores Teciduais de Metaloproteinases/sangue
14.
Front Immunol ; 9: 1402, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29967622

RESUMO

The potential consequences of parasitic infections on a person's immune responsiveness to unrelated antigens are often conjectured upon in relationship to allergic responses and autoimmune diseases. These considerations sometimes extend to whether parasitic infection of pregnant women can influence the outcomes of responses by their offspring to the immunizations administered during national Expanded Programs of Immunization. To provide additional data to these discussions, we have enrolled 99 close-to-term pregnant women in western Kenya and determined their Schistosoma mansoni and Plasmodium falciparum infection status. At 2 years of age, when the initial immunization schedule was complete, we determined their children's IgG antibody levels to tetanus toxoid, diphtheria toxoid, and measles nucleoprotein (N-protein) antigens using a multiplex assay. We also monitored antibody responses during the children's first 2 years of life to P. falciparum MSP119 (PfMSP119), S. mansoni Soluble Egg Antigen (SEA), Ascaris suum hemoglobin (AsHb), and Strongyloides stercoralis (SsNIE). Mothers' infections with either P. falciparum or S. mansoni had no impact on the level of antibody responses of their offspring or the proportion of offspring that developed protective levels of antibodies to either tetanus or diphtheria antigens at 2 years of age. However, children born of S. mansoni-positive mothers and immunized for measles at 9 months of age had significantly lower levels of anti-measles N-protein antibodies when they were 2 years old (p = 0.007) and a lower proportion of these children (62.5 vs. 90.2%, OR = 0.18, 95% CI = 0.04-0.68, p = 0.011) were considered positive for measles N-protein antibodies. Decreased levels of measles antibodies may render these children more susceptible to measles infection than children whose mothers did not have schistosomiasis. None of the children demonstrated responses to AsHb or SsNIE during the study period. Anti-SEA and anti-PfMSP119 responses suggested that 6 and 70% of the children acquired schistosomes and falciparum malaria, respectively, during the first 2 years of life.

15.
BMC Infect Dis ; 14: 316, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24912586

RESUMO

BACKGROUND: Human Immunodeficiency Virus (HIV) and Schistosomiasis co-infection is common among residents at the shores of Lake Victoria in Kenya. About 36% of this population initiating antiretroviral therapy (ART) experience Immune Reconstitution Inflammatory Syndrome (IRIS) that complicates recovery. Several IL-23R alleles have been associated with susceptibility to both autoimmune and inflammatory diseases through T-helper type 17 (TH17) cells. However, whether or not variants within the IL-23R increase susceptibility to IRIS in western Kenya is unknown. The objective of the current study was to determine the association between IL-23R gene polymorphisms, CD4+ cell counts and HIV RNA levels and IRIS in HIV and Schistosoma mansoni co-infected patients undergoing highly active anti-retroviral therapy (HAART). METHODS: A three-month case-control study was conducted on antiretroviral naïve schistosomiasis/HIV co-infected fishermen starting HAART in Uyoma Rarieda, Siaya County, Kenya. Seventy one patients were sampled at baseline and followed up for three months, to establish if they developed Schistosoma-related IRIS. In addition, the CD4+ cell counts and HIV RNA levels were determined in pre- and post-administration of HAART. Variations at five polymorphic sites of IL-23R (rs1884444, rs11465754, rs6682925, rs7530511 and rs7539625) based on >10% minor allele frequency in Yoruban reference population was determined using Allelic Discrimination Assay. The association between the five variants and susceptibility to IRIS was determined using logistic regression while controlling for potential confounders. In addition, the functional differences between the baseline CD4 + Cell counts and viral loads were determined using medians while across IL-23R genotypes were determined using Kruskal-Wallis tests. RESULTS: Overall, 26 (36.6%) patients developed schistosomiasis-associated IRIS at a median age of 35.5 years. Carriage of the TT genotype at the non-synonymous rs1884444 T > G relative to GG, was associated with a decreased risk of schistosomiasis-associated IRIS (OR, 0.25, 95% CI, 0.07-0.96, P = 0.043) while both baseline CD4+ cell counts and viral loads had no association with IRIS. CONCLUSION: These findings indicate that the non-synonymous variant rs1884444 T > G of IL-23R is associated with a decreased risk to schistosomiasis-associated IRIS. However, additional studies in a larger cohort and with an all inclusive polymorphic variants in the synonymous and non-synonymous regions need to be evaluated.


Assuntos
Infecções por HIV/genética , Síndrome Inflamatória da Reconstituição Imune/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina/genética , Esquistossomose/genética , Adulto , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Estudos de Casos e Controles , Coinfecção , Feminino , Frequência do Gene , Predisposição Genética para Doença , Infecções por HIV/tratamento farmacológico , Humanos , Síndrome Inflamatória da Reconstituição Imune/etiologia , Quênia , Masculino , Esquistossomose/complicações , Carga Viral/genética , Adulto Jovem
16.
Am J Trop Med Hyg ; 89(1): 42-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23669231

RESUMO

Previously, we have shown that persons with human immunodeficiency virus 1 (HIV-1) infection and reduced CD4(+) T-lymphocyte counts excrete significantly fewer Schistosoma mansoni eggs than HIV-1-negative persons with similar intensities of schistosome infections. To determine how antiretroviral therapy (ART) might affect egg excretion, we conducted a study of HIV+ adults living in an area highly endemic for S. mansoni as they began an ART program. Fecal egg excretion and CD4(+) T-lymphocyte counts were evaluated at enrollment as well as 2 and 4 weeks after initiation of ART. Fourteen individuals who were Kato-Katz-negative at enrollment subsequently started excreting S. mansoni eggs accompanied by a significant increase in CD4(+) T lymphocytes (P = 0.004). Study participants who were S. mansoni egg-positive at enrollment and received both praziquantel and ART also showed significantly increased CD4(+) T-lymphocyte counts compared with baseline (P < 0.0001). Our data support a role for CD4(+) T lymphocytes in S. mansoni egg excretion.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Fezes/parasitologia , Infecções por HIV/complicações , Contagem de Ovos de Parasitas , Esquistossomose mansoni/complicações , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Coinfecção/tratamento farmacológico , Coinfecção/parasitologia , Coinfecção/virologia , Fezes/virologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/parasitologia , HIV-1 , Humanos , Praziquantel/uso terapêutico , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/virologia
17.
Am J Trop Med Hyg ; 87(5): 862-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22987658

RESUMO

A better understanding of the mechanism of anemia associated with Schistosoma mansoni infection might provide useful information on how treatment programs are implemented to minimize schistosomiasis-associated morbidity and maximize treatment impact. We used a cross-sectional study with serum samples from 206 Kenyan school children to determine the mechanisms in S. mansoni-associated anemia. Serum ferritin and soluble transferrin receptor levels were measured by using an enzyme-linked immunosorbent assay. Results suggest that S. mansoni-infected persons are more likely (odds ratio = 3.68, 95% confidence interval = 1.33-10.1) to have levels of serum ferritin (> 100 ng/mL) that are associated with anemia of inflammation (AI) than S. mansoni-uninfected children. Our results suggest that AI is the most common form of anemia in S. mansoni infections. In contrast, the mechanism of anemia in S. mansoni-uninfected children was iron deficiency. Moreover, the prevalence of AI in the study participants demonstrated a significant trend with S. mansoni infection intensity (P < 0.001). Our results are consistent with those observed in S. japonicum-associated anemia.


Assuntos
Anemia/complicações , Schistosoma mansoni/isolamento & purificação , Esquistossomose/complicações , Anemia/fisiopatologia , Animais , Criança , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Humanos , Quênia/epidemiologia , Receptores da Transferrina/sangue , Esquistossomose/epidemiologia , Esquistossomose/parasitologia , Classe Social
18.
Parasit Vectors ; 5: 182, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22937890

RESUMO

BACKGROUND: Schistosome and soil-transmitted helminth (STH) infections are recognized as major global public health problems, causing severe and subtle morbidity, including significant educational and nutritional effects in children. Although effective and safe drugs are available, ensuring access to these drugs by all those at risk of schistosomiasis and STHs is still a challenge. Community-directed intervention (CDI) has been used successfully for mass distribution of drugs for other diseases such as onchocerciasis and lymphatic filariasis. A national control programme is yet to be instituted in Kenya and evidence for cost-effective strategies for reaching most affected communities is needed. This study evaluated the effectiveness and feasibility of the CDI strategy in the control of schistosomiasis and STHs, in East Uyoma location, Rarieda district, a community of western Kenya that is highly endemic for both infections. RESULTS: Pre-treatment prevalence of S. mansoni averaged 17.4% (range 5-43%) in the entire location. Treatment coverage in different villages ranged from 54.19 to 96.6% by community drug distributor (CDD) records. Assessment from a household survey showed coverage of 52.3 -91.9% while the proportion of homesteads (home compounds) covered ranged from 54.9-98.5%. Six months after one round of drug distribution, the prevalence levels of S. mansoni, hookworm and Trichuris trichura infections were reduced by 33.2%, 69.4% and 42.6% respectively. CONCLUSIONS: This study shows that CDI is an accepted and effective strategy in the mass treatment of schistosomiasis and STH infections in resource constrained communities in Kenya and may be useful in similar communities elsewhere. A controlled trial comparing CDI and school based mass drug administration to demonstrate their relative advantages is ongoing.


Assuntos
Anti-Helmínticos/uso terapêutico , Atenção à Saúde/métodos , Helmintíase/tratamento farmacológico , Infecções por Uncinaria/tratamento farmacológico , Esquistossomose/tratamento farmacológico , Tricuríase/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Albendazol/efeitos adversos , Albendazol/economia , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/efeitos adversos , Anti-Helmínticos/economia , Criança , Pré-Escolar , Análise Custo-Benefício , Estudos de Viabilidade , Feminino , Helmintíase/epidemiologia , Helmintíase/parasitologia , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/parasitologia , Humanos , Quênia/epidemiologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Praziquantel/efeitos adversos , Praziquantel/economia , Praziquantel/uso terapêutico , Prevalência , Esquistossomose/epidemiologia , Esquistossomose/parasitologia , Fatores Socioeconômicos , Solo/parasitologia , Tricuríase/epidemiologia , Tricuríase/parasitologia
19.
Lancet Infect Dis ; 10(9): 603-11, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20705516

RESUMO

BACKGROUND: Schistosomiasis is an important parasitic disease in Kenya. Decreasing susceptibility of schistosomes to praziquantel, the major drug used to reduce disease morbidity, has made assessment of new antischistosomal drugs a priority. We aimed to assess the safety and efficacy of an artesunate-based combination drug in the treatment of schistosomiasis. METHODS: In this open-label randomised trial in Rarieda district of western Kenya, we enrolled school children (aged 6-15 years) who had Schistosoma mansoni infection according to duplicate Kato-Katz thick smears from a stool sample. Computer-generated block randomisation was used to assign children (1:1) to receive artesunate (100 mg) with sulfalene (also known as sulfamethoxypyrazine; 250 mg) plus pyrimethamine (12.5 mg) as one dose every 24 h for 3 days or one dose of praziquantel (40 mg/kg per day). The primary efficacy endpoint was the number of participants cured 28 days after treatment. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01054651. RESULTS: Between October and December, 2009, 212 children were enrolled and assigned to receive artesunate with sulfalene plus pyrimethamine (n=106) or praziquantel (n=106). 69 patients (65%) were cured in the praziquantel treatment group compared with 15 (14%) in the artesunate with sulfalene plus pyrimethamine treatment group (p<0.0001). Adverse events were less common in patients taking artesunate with sulfalene plus pyrimethamine than in those taking praziquantel (22% [n=23] vs 49% [n=52], p<0.0001), and no drug-related serious adverse events occurred. INTERPRETATION: The standard treatment with praziquantel is more effective than artesunate with sulfalene plus pyrimethamine in the treatment of children with S mansoni infection in western Kenya. Whether artemisinin-based combination therapy has a role in the treatment of schistosomiasis is unclear.


Assuntos
Artemisininas/uso terapêutico , Pirimetamina/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Sulfaleno/uso terapêutico , Adolescente , Amebicidas/efeitos adversos , Amebicidas/uso terapêutico , Animais , Antiprotozoários/efeitos adversos , Antiprotozoários/uso terapêutico , Artemisininas/efeitos adversos , Artesunato , Criança , Pré-Escolar , Quimioterapia Combinada , Feminino , Humanos , Lactente , Quênia , Masculino , Pirimetamina/efeitos adversos , Schistosoma mansoni , Esquistossomose mansoni/classificação , Sulfaleno/efeitos adversos
20.
J Infect Dis ; 202(3): 399-405, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20560767

RESUMO

BACKGROUND: Age prevalence curves for areas in which schistosomiasis is endemic suggest that humans develop partial immunity to reinfection beginning in early adolescence. We conducted a 2-year longitudinal study to determine whether children infected with Schistosoma mansoni develop protection-related immune responses after treatment with praziquantel and whether the development of these immune responses is accelerated by frequent treatment after reinfection. METHODS: Children (8-10 years old) were tested for S. mansoni every 4 months and treated with praziquantel when positive (arm A; n=68) or were tested and treated at the end of the 2-year follow-up period (arm B; n=49). RESULTS: Children in arm A who remained free of infection during follow-up had significantly higher baseline levels of schistosome-specific immunoglobulin E (IgE) than did children with > or =2 repeat diagnoses of S. mansoni infection. Children with > or =2 repeat diagnoses of S. mansoni infection had significantly increased levels of anti-schistosome IgE and CD23(+) B cells after receiving > or =3 praziquantel treatments over the course of follow-up. No increase in either parameter was seen in children who received only the baseline praziquantel treatment. CONCLUSIONS: B cell activation and anti-schistosome IgE are associated with resistance to S. mansoni in children, and these immunological parameters can be increased by multiple rounds of infections and praziquantel-induced cures.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Linfócitos B/imunologia , Imunoglobulina E/sangue , Receptores de IgE/análise , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Animais , Anti-Helmínticos/uso terapêutico , Linfócitos B/química , Criança , Feminino , Humanos , Quênia , Estudos Longitudinais , Masculino , Praziquantel/uso terapêutico , Recidiva , Esquistossomose mansoni/tratamento farmacológico
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