Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
PLoS Med ; 16(1): e1002727, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30640916

RESUMO

BACKGROUND: A previous analysis of the impact of drought in Africa on HIV demonstrated an 11% greater prevalence in HIV-endemic rural areas attributable to local rainfall shocks. The Lesotho Population-Based HIV Impact Assessment (LePHIA) was conducted after the severe drought of 2014-2016, allowing for reevaluation of this relationship in a setting of expanded antiretroviral coverage. METHODS AND FINDINGS: LePHIA selected a nationally representative sample between November 2016 and May 2017. All adults aged 15-59 years in randomly selected households were invited to complete an interview and HIV testing, with one woman per household eligible to answer questions on their experience of sexual violence. Deviations in rainfall for May 2014-June 2016 were estimated using precipitation data from Climate Hazards Group InfraRed Precipitation with Station Data (CHIRPS), with drought defined as <15% of the average rainfall from 1981 to 2016. The association between drought and risk behaviors as well as HIV-related outcomes was assessed using logistic regression, incorporating complex survey weights. Analyses were stratified by age, sex, and geography (urban versus rural). All of Lesotho suffered from reduced rainfall, with regions receiving 1%-36% of their historical rainfall. Of the 12,887 interviewed participants, 93.5% (12,052) lived in areas that experienced drought, with the majority in rural areas (7,281 versus 4,771 in urban areas). Of the 835 adults living in areas without drought, 520 were in rural areas and 315 in urban. Among females 15-19 years old, living in a rural drought area was associated with early sexual debut (odds ratio [OR] 3.11, 95% confidence interval [CI] 1.43-6.74, p = 0.004), and higher HIV prevalence (OR 2.77, 95% CI 1.19-6.47, p = 0.02). It was also associated with lower educational attainment in rural females ages 15-24 years (OR 0.44, 95% CI 0.25-0.78, p = 0.005). Multivariable analysis adjusting for household wealth and sexual behavior showed that experiencing drought increased the odds of HIV infection among females 15-24 years old (adjusted OR [aOR] 1.80, 95% CI 0.96-3.39, p = 0.07), although this was not statistically significant. Migration was associated with 2-fold higher odds of HIV infection in young people (aOR 2.06, 95% CI 1.25-3.40, p = 0.006). The study was limited by the extensiveness of the drought and the small number of participants in the comparison group. CONCLUSIONS: Drought in Lesotho was associated with higher HIV prevalence in girls 15-19 years old in rural areas and with lower educational attainment and riskier sexual behavior in rural females 15-24 years old. Policy-makers may consider adopting potential mechanisms to mitigate the impact of income shock from natural disasters on populations vulnerable to HIV transmission.


Assuntos
Secas , Infecções por HIV/prevenção & controle , Adolescente , Adulto , Fatores Etários , Secas/estatística & dados numéricos , Feminino , Infecções por HIV/epidemiologia , Humanos , Lesoto/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Sexuais , Inquéritos e Questionários , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
2.
BMC Health Serv Res ; 19(1): 194, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30917823

RESUMO

BACKGROUND: Despite malaria prevention initiatives, malaria remains a major health problem in Malawi, especially for pregnant mothers and children under the age of five. To reduce the malaria burden, Malawi established its first National Malaria Control Programme in 1984. Implementation of evidence-based policies contributed to malaria prevalence dropping from 43% in 2010 to 22% in 2017. In this study, we explored challenges to implementing malaria policies in Malawi from the perspective of key stakeholders in the country. METHODS: In this qualitative study, we conducted in-depth interviews with 27 key informants from April to July 2015. We stopped sampling new participants when themes became saturated. Purposive and snowballing sampling techniques were used to identify key informants including malaria researchers that were policy advisors, policy makers, programme managers, and other key stakeholders. Interviews were conducted in English, recorded and transcribed, and imported into QSR Nvivo 11 for coding and analysis. Data were analysed using the qualitative content analysis approach. RESULTS: Participants identified three main categories of challenges to the implementation of malaria policies. First structural challenges include inadequate resources, unavailability of trained staff, poor supervision and mentorship of staff, and personnel turnover in government. The second challenge is unilateral implementation of policies. The third category is the inadequately informed policy development and includes lack of platforms to engage with communities, top-down approach in policy formulation and lack of understanding of socio-cultural factors affecting policy uptake by communities. CONCLUSIONS: Policy makers should recognize that inadequate support of policy objectives leads to an implementation gap. Therefore, policy development and implementation should not be viewed as distinct, but rather as interactive processes shaping each other. Support for health policy and systems research should be mobilized to strengthen the health system. Detailed assessment of implementation challenges to specific malaria policies should also be conducted to address these challenges and support the shift from the paradigm of malaria prevention and control to elimination in Malawi.


Assuntos
Política de Saúde , Malária/prevenção & controle , Formulação de Políticas , Pessoal Administrativo , Atenção à Saúde , Erradicação de Doenças , Humanos , Malária/epidemiologia , Malaui/epidemiologia , Pesquisa Qualitativa
3.
Malar J ; 16(1): 84, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28219435

RESUMO

BACKGROUND: The growing resistance of Plasmodium falciparum to sulfadoxine-pyrimethamine (SP) treatment for uncomplicated malaria led to a recommendation by the World Health Organization for the use of artemisinin-based combination therapy. Inevitably, concerns were also raised surrounding the use of SP for intermittent prevention treatment of malaria during pregnancy (IPTp) amidst the lack of alternative drugs. Malawi was the first country to adopt intermittent prevention treatment with SP in 1993, and updated in 2013. This case study examines the policy updating process and the contribution of research and key stakeholders to this process. The findings support the development of a malaria research-to-policy framework in Malawi. METHODS: Documents and evidence published from 1993 to 2012 were systematically reviewed in addition to key informant interviews. RESULTS: The online search identified 170 potential publications, of which eight from Malawi met the inclusion criteria. Two published studies from Malawi were instrumental in the WHO policy recommendation which in turn led to the updating of national policies. The updated policy indicates that more than two SP doses, as informed by research, overcome the challenges of the first policy of two SP doses only because of ineffectiveness by P. falciparum resistance and the global lack of replacement drugs to SP for IPTp. CONCLUSION: International WHO recommendations facilitated a smooth policy change driven by motivated local leadership with technical and financial support from development partners. Policy development and implementation should include key stakeholders and use local malaria research in a research-to-policy framework.


Assuntos
Antimaláricos/administração & dosagem , Quimioprevenção/métodos , Política de Saúde , Malária Falciparum/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Pirimetamina/administração & dosagem , Sulfadoxina/administração & dosagem , Combinação de Medicamentos , Feminino , Humanos , Malaui , Gravidez
4.
Malar J ; 16(1): 246, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28606149

RESUMO

BACKGROUND: Malaria research can play a vital role in addressing the malaria burden in Malawi. An organized approach in addressing malaria in Malawi started in 1984 by the establishment of the first National Malaria Control Programme and research was recognized to be significant. This study aimed to assess the type and amount of malaria research conducted in Malawi from 1984 to 2016 and its related source of funding. METHODS: A systematic literature search was conducted in the Medline/PubMed database for Malawian publications and approved malaria studies from two Ethical Committees were examined. Bibliometric analysis was utilized to capture the affiliations of first and senior/last authors, funding acknowledgements, while titles, abstracts and accessed full text were examined for research type. RESULTS: A total of 483 publications and 165 approved studies were analysed. Clinical and basic research in the fields of malaria in pregnancy 105 (21.5%), severe malaria 97 (20.1%) and vector and/or agent dynamics 69 (14.3%) dominated in the publications while morbidity 33 (20%), severe malaria 28 (17%) and Health Policy and Systems Research 24 (14.5%) dominated in the approved studies. In the publications, 146 (30%) first authors and 100 (21%) senior authors, and 88 (53.3%) principal investigators in approved studies were affiliated to Malawian-based institutions. Most researchers were affiliated to the Malawi-Liverpool Wellcome Trust, College of Medicine, Blantyre Malaria Project, Ministry of Health, and Malaria Alert Centre. The major malaria research funders were the National Institute for Health/USA, Wellcome Trust and the US Agency for International Development. Only three (2.5%) out of 118 journals publishing research on malaria in Malawi were from Africa and the Malaria Journal, with 76 (15.7%) publications, published most of the research from Malawi, followed by the American Journal of Tropical Medicine and Hygiene with 57 (11.8%) in comparison to only 13 (2.7%) published in the local Malawi Medical Journal. CONCLUSIONS: Clinical and basic research, which is mostly funded externally, in the fields of malaria in pregnancy, severe malaria and vector and/or agent dynamics dominated, while health policy and system research was least supported. The quantity may reflect scientific research activity but the initial primary impact is contribution to policy development.


Assuntos
Malária , Pesquisa/estatística & dados numéricos , Malária/epidemiologia , Malária/prevenção & controle , Malária/terapia , Malaui , Pesquisa/classificação , Pesquisa/economia
5.
Health Res Policy Syst ; 15(1): 97, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29157288

RESUMO

BACKGROUND: The existing gap between research evidence and public health practice has attributed to the unmet Millennium Development Goals in Africa and consequently, has stimulated the development of frameworks to enhance knowledge translation. These efforts aim at maximising health research utilisation in policy and practice to address the world's disease burdens, including malaria. This study aimed at developing a contextual framework to improve the utilisation of malaria research for policy development in Malawi. METHODS: The study used two approaches including: two case studies of policy analysis exploring the policy-making process in Malawi, utilisation of local malaria research, and the role of key stakeholders in policy formulation process; and the assessment of facilitating factors and barriers to malaria research utilisation for policy-making in Malawi. RESULTS: From the case studies' lessons and elements identified during the assessment of facilitating factors and barriers, a framework is developed to promote an integrated approach to knowledge translation. In this framework the Ministry of Health is considered as the main user of knowledge from research through the demand created by the research directorate and the National Malaria Control Programme. Key documents identified as being particularly relevant to the Ministry of Health for purposes of knowledge translation include the National Health Research Agenda, Guidelines for Policy Development and Analysis, and Guidelines for Evidence Use in Policy-making. Institutions conducting academic and policy-relevant malaria research in Malawi are identified and a consolidation of their linkages with the users of research is established through the Knowledge Translation Unit, the Evidence Informed decision-making Centre, and the African Institute for Development Policy. Equally, key players in this framework are the funding partners for both research and programmes that need to see accountability and impact of their support. Independent advisors, partners, and consultants also have their vital role in the process. CONCLUSION: The framework offers a practical basis for the factors identified and their linkages to promote a co-ordinated approach to malaria research utilisation in policy-making. Its applicability and success hinges on its wider dissemination and ownership by the government through the National Malaria Control Programme.


Assuntos
Antimaláricos/uso terapêutico , Pesquisa Biomédica , Medicina Baseada em Evidências , Política de Saúde , Malária/tratamento farmacológico , Formulação de Políticas , Pesquisa Translacional Biomédica , Humanos , Malaui , Saúde Pública
6.
Malar J ; 15(1): 264, 2016 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-27165269

RESUMO

BACKGROUND: Cotrimoxazole (CTX) prophylaxis, recommended in HIV-exposed uninfected (HEU) children primarily against HIV-related opportunistic infections, has been shown to have some efficacy against Plasmodium falciparum malaria. The effects of CTX prophylaxis on the acquisition of P. falciparum antigen specific CD4(+) T cells-mediated immunity in HEU children is still not fully understood. METHODS: Peripheral blood was collected from HEU and HIV-unexposed uninfected (HUU) children at 6, 12 and 18 months of age. Proportion of CD4(+) T cells subsets were determined by immunophenotyping. P. falciparum antigen-specific CD4(+) T cells responses were measured by intracellular cytokine staining assay. RESULTS: There were no differences in the proportions of naïve, effector and memory CD4(+) T cell subsets between HEU and HUU children at all ages. There was a trend showing acquisition of P. falciparum-specific IFN-γ and TNF-producing CD4(+) T cells with age in both HUU and HEU children. There was, however, lower frequency of P. falciparum-specific IFN-γ-producing CD4(+) T cells in HEU compared to HUU at 6 and 12 months, which normalized 6 months after stopping CTX prophylaxis. CONCLUSION: The results demonstrate that there is delayed acquisition of P. falciparum-specific IFN-γ-producing CD4(+) T cells in HEU children on daily cotrimoxazole prophylaxis, which is evident at 6 and 12 months of age in comparison to HUU age-matched controls. However, whether this delayed acquisition of P. falciparum-specific IFN-γ-producing CD4(+) T cells leads to higher risk to malaria disease remains unknown and warrants further investigation.


Assuntos
Antimaláricos/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Quimioprevenção/métodos , Malária Falciparum/imunologia , Exposição Materna , Plasmodium falciparum/imunologia , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem , Citocinas/análise , Feminino , Infecções por HIV/imunologia , Humanos , Imunofenotipagem , Lactente , Malaui , Masculino , Gravidez
7.
Malar J ; 15(1): 512, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27760552

RESUMO

BACKGROUND: Research on various determinants of health is key in providing evidence for policy development, thereby leading to successful interventions. Utilization of research is an intricate process requiring an understanding of contextual factors. The study was conducted to assess enhancing factors and barriers of research utilization for malaria policy development in Malawi. METHODS: Qualitative research approach was used through in-depth interviews with 39 key informants that included malaria researchers, policy makers, programme managers, and key stakeholders. Purposive sampling and snowballing techniques were used in identifying key informants. Interview transcripts were entered in QSR Nvivo 11 software for coding and analysis. RESULTS: Respondents identified global efforts as key in advancing knowledge translation, while local political will has been conducive for research utilization. Other factors were availability of research, availability of diverse local researchers and stakeholders supporting knowledge translation. While barriers included: lack of platforms for researcher-public engagement, politics, researchers' lack of communication skills, lack of research collaborations, funder driven research, unknown World Health Organization policy position, and the lack of a malaria research repository. CONCLUSION: Overall, the study identified facilitating factors to malaria research utilization for policy development in Malawi. These factors need to be systematically coordinated to address the identified barriers and improve on malaria research utilization in policy development. Malaria research can be key in the implementation of evidence-based interventions to reduce the malaria burden and assist in the paradigm shift from malaria control to elimination in Malawi.


Assuntos
Pesquisa Biomédica , Controle de Doenças Transmissíveis/organização & administração , Transmissão de Doença Infecciosa/prevenção & controle , Entomologia , Malária/epidemiologia , Malária/prevenção & controle , Formulação de Políticas , Pessoal Administrativo , Feminino , Humanos , Entrevistas como Assunto , Malaui/epidemiologia , Masculino , Pesquisa Translacional Biomédica
8.
Health Res Policy Syst ; 14(1): 41, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27246503

RESUMO

BACKGROUND: In 1993, Malawi changed its first-line anti-malarial treatment for uncomplicated malaria from chloroquine to sulfadoxine-pyrimethamine (SP), and in 2007, it changed from SP to lumefantrine-artemether. The change in 1993 raised concerns about whether it had occurred timely and whether it had potentially led to early development of Plasmodium falciparum resistance to SP. This case study examined evidence from Malawi in order to assess if the policy changes were justifiable and supported by evidence. METHODS: A systematic review of documents and published evidence between 1984 and 1993, when chloroquine was the first-line drug, and 1994 and 2007, when SP was the first-line drug, was conducted herein. The review was accompanied with key informant interviews. RESULTS: A total of 1287 publications related to malaria drug policy changes in sub-Saharan Africa were identified. Using the inclusion criteria, four articles from 1984 to 1993 and eight articles from 1994 to 2007 were reviewed. Between 1984 and 1993, three studies reported on chloroquine poor efficacy prompting policy change according to WHO's recommendation. From 1994 to 2007, four studies conducted in the early years of policy change reported a high SP efficacy of above 80%, retaining it as a first-line drug. Unpublished sentinel site studies between 2005 and 2007 showed a reduced efficacy of SP, influencing policy change to lumefantrine-artemether. The views of key informants indicate that the switch from chloroquine to SP was justified based on local evidence despite unavailability of WHO's policy recommendations, while the switch to lumefantrine-artemether was uncomplicated as the country was following the recommendations from WHO. CONCLUSION: Ample evidence from Malawi influenced and justified the policy changes. Therefore, locally generated evidence is vital for decision making during policy change.


Assuntos
Antimaláricos/uso terapêutico , Pesquisa Biomédica , Resistência a Medicamentos , Medicina Baseada em Evidências , Política de Saúde , Malária/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/farmacologia , Artemeter , Artemisininas/uso terapêutico , Cloroquina/uso terapêutico , Combinação de Medicamentos , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Humanos , Lumefantrina , Malária/parasitologia , Malária Falciparum/tratamento farmacológico , Malaui , Plasmodium falciparum/patogenicidade , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Resultado do Tratamento
9.
BMC Immunol ; 16: 50, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26315539

RESUMO

BACKGROUND: As a result of successful PMTCT programs, children born from HIV-infected mothers are now effectively protected from contracting the infection. However, it is not well known whether in utero exposure to the virus and the subsequent exposure to Cotrimoxazole (CTX) prophylaxis affect the cell mediated immune system of the children. This observational prospective study was aimed at determining how CD4(+) T, CD8(+) T and B cell subsets varied in HIV-exposed but uninfected (HEU) children at different ages. METHODS: We recruited HEU and HIV-unexposed and uninfected (HUU) children from 6 months of age and followed them up until they were 18 months old. HEU children received daily CTX prophylaxis beginning at 6 weeks of age until when 12 months of age. Venous blood samples were collected 6 monthly and analysed for different subsets of CD8(+) T, B cells and totalCD4(+) T cells. RESULTS: At 6 months of age, HEU children had a lower percentage of total CD4(+) T cells compared to HUU children and a lower proportion of naïve CD8(+) T cells but higher percentage of effector memory CD8(+) T cells compared to HUU children. HEU and HUU children had similar proportions of all B cell subsets at all ages. CONCLUSIONS: The study showed that the subtle variations in CD4(+) and CD8(+) T cell subsets observed at 6 months do not last beyond 12 months of age, suggesting that HEU children have a robust cell-mediated immune system during first year of life. TRIAL REGISTRATION: This article report is not based on results of a controlled health-care intervention.


Assuntos
Subpopulações de Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Infecções por HIV/tratamento farmacológico , Humanos , Lactente , Contagem de Linfócitos , Malaui
10.
N Engl J Med ; 362(9): 812-22, 2010 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-20200385

RESUMO

BACKGROUND: Streptococcus pneumoniae is a leading and serious coinfection in adults with human immunodeficiency virus (HIV) infection, particularly in Africa. Prevention of this disease by vaccination with the current 23-valent polysaccharide vaccine is suboptimal. Protein conjugate vaccines offer a further option for protection, but data on their clinical efficacy in adults are needed. METHODS: In this double-blind, randomized, placebo-controlled clinical efficacy trial, we studied the efficacy of a 7-valent conjugate pneumococcal vaccine in predominantly HIV-infected Malawian adolescents and adults who had recovered from documented invasive pneumococcal disease. Two doses of vaccine were given 4 weeks apart. The primary end point was a further episode of pneumococcal infection caused by vaccine serotypes or serotype 6A. RESULTS: From February 2003 through October 2007, we followed 496 patients (of whom 44% were male and 88% were HIV-seropositive) for 798 person-years of observation. There were 67 episodes of pneumococcal disease in 52 patients, all in the HIV-infected subgroup. In 24 patients, there were 19 episodes that were caused by vaccine serotypes and 5 episodes that were caused by the 6A serotype. Of these episodes, 5 occurred in the vaccine group and 19 in the placebo group, for a vaccine efficacy of 74% (95% confidence interval [CI], 30 to 90). There were 73 deaths from any cause in the vaccine group and 63 in the placebo group (hazard ratio in the vaccine group, 1.18; 95% CI, 0.84 to 1.66). The number of serious adverse events within 14 days after vaccination was significantly lower in the vaccine group than in the placebo group (3 vs. 17, P=0.002), and the number of minor adverse events was significantly higher in the vaccine group (41 vs. 13, P=0.003). CONCLUSIONS: The 7-valent pneumococcal conjugate vaccine protected HIV-infected adults from recurrent pneumococcal infection caused by vaccine serotypes or serotype 6A. (Current Controlled Trials number, ISRCTN54494731.)


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Infecções por HIV/complicações , Vacinas Pneumocócicas , Pneumonia Pneumocócica/prevenção & controle , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Método Duplo-Cego , Feminino , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Vacinas Pneumocócicas/efeitos adversos , Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/etiologia , Fatores de Risco , Streptococcus pneumoniae/classificação , Vacinas Conjugadas , Adulto Jovem
11.
Microbiol Spectr ; 11(3): e0314822, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37071009

RESUMO

Population-based HIV Impact Assessments (PHIAs) are national household (HH) surveys that provide HIV diagnosis and CD4 testing with an immediate return of results. Accurate CD4 results improve HIV-positive participants' clinical care and inform the effectiveness of HIV programs. Here, we present CD4 results from the PHIA surveys that were conducted in 11 countries in sub-Saharan Africa between 2015 and 2018. All of the HIV-positive participants and 2 to 5% of the HIV-negative participants were offered Pima CD4 (Abbott, IL, USA) point-of-care (POC) tests. The quality of the CD4 test was ensured by conducting instrument verification, comprehensive training, quality control, a review of testing errors and an analysis of unweighted CD4 data by HIV status, age, gender, and antiretroviral (ARV) treatment status. Overall, CD4 testing was completed for 23,085 (99.5%) of the 23,209 HIV-positive and 7,329 (2.7%) of the 270,741 negative participants in 11 surveys. The instrument error rate was 11.3% (range, 4.4% to 15.7%). The median CD4 values among HIV-positive and HIV-negative participants (aged 15+) were 468 cells/mm3 (interquartile range [IQR], 307 to 654) and 811 cells/mm3 (IQR, 647 to 1,013), respectively. Among the HIV-positive participants (aged 15+), those with detectable ARVs had higher CD4 values (508 cells/mm3) than those with undetectable ARVs (385.5 cells/mm3). Among the HIV-positive participants (aged 15+), 11.4% (2,528/22,253) had a CD4 value of less than 200 cells/mm3, and approximately half of them (1,225/2,528 = 48.5%) had detectable ARVs, whereas 51.5% (1,303/2,528) had no detectable ARVs (P < 0.0001). We successfully implemented high quality POC CD4 testing using Pima instruments. Our data come from nationally representative surveys in 11 countries and provide unique insights regarding the CD4 distribution among HIV-positive individuals as well as the baseline CD4 values among HIV-negative individuals. IMPORTANCE The manuscript describes CD4 levels among HIV-positive individuals and baseline CD4 levels among HIV-negative individuals from 11 sub-Saharan countries, thereby highlighting the importance of CD4 markers in the context of the HIV epidemic. Despite increased ARV access in each country, advanced HIV disease (CD4 < 200 cells/mm3) persists among approximately 11% of HIV-positive individuals. Therefore, it is important that our findings are shared with the scientific community to assist with similar implementations of point-of-care testing and to conduct a review of HIV programmatic gaps.


Assuntos
Infecções por HIV , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4 , HIV , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Testes Imediatos , Indicadores de Qualidade em Assistência à Saúde
12.
AIDS Res Hum Retroviruses ; 39(2): 57-67, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36401361

RESUMO

Nationally representative surveys provide an opportunity to assess trends in recent human immunodeficiency virus (HIV) infection based on assays for recent HIV infection. We assessed HIV incidence in Kenya in 2018 and trends in recent HIV infection among adolescents and adults in Kenya using nationally representative household surveys conducted in 2007, 2012, and 2018. To assess trends, we defined a recent HIV infection testing algorithm (RITA) that classified as recently infected (<12 months) those HIV-positive participants that were recent on the HIV-1 limiting antigen (LAg)-avidity assay without evidence of antiretroviral use. We assessed factors associated with recent and long-term (≥12 months) HIV infection versus no infection using a multinomial logit model while accounting for complex survey design. Of 1,523 HIV-positive participants in 2018, 11 were classified as recent. Annual HIV incidence was 0.14% in 2018 [95% confidence interval (CI) 0.057-0.23], representing 35,900 (95% CI 16,300-55,600) new infections per year in Kenya among persons aged 15-64 years. The percentage of HIV infections that were determined to be recent was similar in 2007 and 2012 but fell significantly from 2012 to 2018 [adjusted odds ratio (aOR) = 0.31, p < .001]. Compared to no HIV infection, being aged 25-34 versus 35-64 years (aOR = 4.2, 95% CI 1.4-13), having more lifetime sex partners (aOR = 5.2, 95% CI 1.6-17 for 2-3 partners and aOR = 8.6, 95% CI 2.8-26 for ≥4 partners vs. 0-1 partners), and never having tested for HIV (aOR = 4.1, 95% CI 1.5-11) were independently associated with recent HIV infection. Although HIV remains a public health priority in Kenya, HIV incidence estimates and trends in recent HIV infection support a significant decrease in new HIV infections from 2012 to 2018, a period of rapid expansion in HIV diagnosis, prevention, and treatment.


Assuntos
Infecções por HIV , Soropositividade para HIV , Adulto , Adolescente , Humanos , Quênia/epidemiologia , Incidência , Parceiros Sexuais
13.
PLoS One ; 16(7): e0254320, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34242324

RESUMO

Although a number of previous studies have shown that different lymphocyte subsets, including B cells, vary with age, how different B cell subsets vary with age in Malawian population has not been shown before. We recruited Malawian participants of different ages and analyzed their venous blood samples for different B cell subsets. We found that both percentage and absolute counts of B cells varied with age peaking in the 7 to 12 months age group. Proportion of naïve B cells was highest in neonates and decreased with age whereas the percentage of memory B cells was lowest in neonates and increased with age. When we zeroed in on the age band within which the proportion of B cells was highest, both classical and activated memory B cells increased with age and the naïve followed the opposite trend. These results provide additional knowledge in our understanding of the dynamics of B cell subsets in individuals of a specific ethnicity as they age.


Assuntos
Subpopulações de Linfócitos B , Humanos , Lactente , Contagem de Linfócitos , Masculino
14.
Curr Res Immunol ; 2: 184-193, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35492400

RESUMO

Cell-mediated responses to immunological stimuli are often localised in inflammatory sites and involve a number of cell types. These responses can be functionally characterised at the single-cell level on the basis of the types of cytokines expressed either in whole blood or PBMCs. The ability to measure antigen-specific cell responses at the single cell level is an important tool with a wide range of potential applications ranging from studies of disease pathogenesis to the evaluation of vaccines. A number of experiments were performed in this study in order to establish the optimal conditions for in vitro stimulation of cytokine production by T cells and monocytes in whole blood samples collected from healthy adult Malawian participants and the optimal staining conditions for various cytokine producing cells. Different stimulation methods and conditions, different culture tubes and incubators and different antibody labelling conditions were assessed in order to establish optimal conditions for detecting cytokine-producing cells in whole blood samples. The use of PMA plus Ionomycin produced highest cytokine-producing T cells whereas LPS was a better stimulant for cytokine producing monocytes. Stimulation of whole blood for 5 h was optimal for cytokine detection in T cells whereas 4 h was optimal for monocytes. BFA was found to be a better Golgi blocker than Monensin and the use of 15 ml Falcon-type polypropylene tubes while stationary resulted in the detection of the highest proportion of cytokine-producing cells. T cells were found to be producers of mainly TNF-α, IFN-γ and IL-2 whereas Monocytes were mainly producing TNF-α and IL-6. Anti-CD3-PerCP (used at a ratio of 1:25), anti-CD14-APC (used at a ratio of 1:50) and anti-cytokine-PE (used at a ratio of 1:12.5) resulted in the best results. The highest cytokine production monocytes were detected when 1 X FACS Lysing solution was used at a volume of 40X that of the whole blood sample compared to the other volumes. These optimal conditions are essential in determination of proportion of cytokine-producing cells using ICS in whole blood.

15.
J Acquir Immune Defic Syndr ; 87(Suppl 1): S17-S27, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34166309

RESUMO

BACKGROUND: Conducting HIV surveys in resource-limited settings is challenging because of logistics, limited availability of trained personnel, and complexity of testing. We described the procedures and systems deemed critical to ensure high-quality laboratory data in the population-based HIV impact assessments and large-scale household surveys. METHODS: Laboratory professionals were engaged in every stage of the surveys, including protocol development, site assessments, procurement, training, quality assurance, monitoring, analysis, and reporting writing. A tiered network of household, satellite laboratories, and central laboratories, accompanied with trainings, optimized process for blood specimen collection, storage, transport, and real-time monitoring of specimen quality, and test results at each level proved critical in maintaining specimen integrity and high-quality testing. A plausibility review of aggregate merged data was conducted to confirm associations between key variables as a final quality check for quality of laboratory results. RESULTS: Overall, we conducted a hands-on training for 3355 survey staff across 13 surveys, with 160-387 personnel trained per survey on biomarker processes. Extensive training and monitoring demonstrated that overall, 99% of specimens had adequate volume and 99.8% had no hemolysis, indicating high quality. We implemented quality control and proficiency testing for testing, resolved discrepancies, verified >300 Pima CD4 instruments, and monitored user errors. Aggregate data review for plausibility further confirmed the high quality of testing. CONCLUSIONS: Ongoing engagement of laboratory personnel to oversee processes at all levels of the surveys is critical for successful national surveys. High-quality population-based HIV impact assessments laboratory data ensured reliable results and demonstrated the impact of HIV programs in 13 countries.


Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV-1 , Ensaio de Proficiência Laboratorial/normas , Países em Desenvolvimento , Monitoramento Epidemiológico , Inquéritos Epidemiológicos , Humanos , Pessoal de Laboratório/educação , Pessoal de Laboratório/normas , Controle de Qualidade
16.
BMC Infect Dis ; 10: 280, 2010 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-20860822

RESUMO

BACKGROUND: Untreated human immunodeficiency virus (HIV) disease disrupts B cell populations causing reduced memory and reduced naïve resting B cells leading to increases in specific co-infections and impaired responses to vaccines. To what extent antiretroviral treatment reverses these changes in an African population is uncertain. METHODS: A cross-sectional study was performed. We recruited HIV-uninfected and HIV-infected Malawian adults both on and off antiretroviral therapy attending the Queen Elizabeth Central hospital in Malawi. Using flow cytometry, we enumerated B cells and characterized memory B cells and compared these measurements by the different recruitment groups. RESULTS: Overall 64 participants were recruited - 20 HIV uninfected (HIV-), 30 HIV infected ART naïve (HIV+N) and 14 HIV-infected ART treated (HIV+T). ART treatment had been taken for a median of 33 months (Range 12-60 months). Compared to HIV- the HIV+N adults had low absolute number of naïve resting B cells (111 vs. 180 cells/µl p = 0.008); reduced memory B cells (27 vs. 51 cells/µl p = 0.0008). The HIV+T adults had B-cell numbers similar to HIV- except for memory B cells that remained significantly lower (30 vs. 51 cells/µl p = 0.02). In the HIV+N group we did not find an association between CD4 count and B cell numbers. CONCLUSIONS: HIV infected Malawian adults have abnormal B-cell numbers. Individuals treated with ART show a return to normal in B-cell numbers but a persistent deficit in the memory subset is noted. This has important implications for long term susceptibility to co-infections and should be evaluated further in a larger cohort study.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Linfócitos B/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Memória Imunológica , Adulto , Estudos Transversais , Feminino , Citometria de Fluxo/métodos , Humanos , Contagem de Linfócitos , Malaui , Masculino , Pessoa de Meia-Idade
17.
Malawi Med J ; 28(3): 115-122, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27895845

RESUMO

BACKGROUND: Streptococcus pneumoniae is a leading and serious coinfection in adults with human immunodeficiency virus (HIV) infection, particularly in Africa. Prevention of this disease by vaccination with the current 23-valent polysaccharide vaccine is suboptimal. Protein conjugate vaccines offer a further option for protection, but data on their clinical efficacy in adults are needed. METHODS: In this double-blind, randomized, placebo-controlled clinical efficacy trial, we studied the efficacy of a 7-valent conjugate pneumococcal vaccine in predominantly HIV-infected Malawian adolescents and adults who had recovered from documented invasive pneumococcal disease. Two doses of vaccine were given 4 weeks apart. The primary end point was a further episode of pneumococcal infection caused by vaccine serotypes or serotype 6A. RESULTS: From February 2003 through October 2007, we followed 496 patients (of whom 44% were male and 88% were HIV-seropositive) for 798 person-years of observation. There were 67 episodes of pneumococcal disease in 52 patients, all in the HIV-infected subgroup. In 24 patients, there were 19 episodes that were caused by vaccine serotypes and 5 episodes that were caused by the 6A serotype. Of these episodes, 5 occurred in the vaccine group and 19 in the placebo group, for a vaccine efficacy of 74% (95% confidence interval [CI], 30 to 90). There were 73 deaths from any cause in the vaccine group and 63 in the placebo group (hazard ratio in the vaccine group, 1.18; 95% CI, 0.84 to 1.66). The number of serious adverse events within 14 days after vaccination was significantly lower in the vaccine group than in the placebo group (3 vs. 17, P = 0.002), and the number of minor adverse events was significantly higher in the vaccine group (41 vs. 13, P = 0.003). CONCLUSIONS: The 7-valent pneumococcal conjugate vaccine protected HIV-infected adults from recurrent pneumococcal infection caused by vaccine serotypes or serotype 6A. (Current Controlled Trials number, ISRCTN54494731.).

18.
PLoS One ; 10(3): e0121643, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25807475

RESUMO

BACKGROUND AND OBJECTIVES: Co-trimoxazole prophylaxis, currently recommended in HIV-exposed, uninfected (HEU) children as protection against opportunistic infections, also has some anti-malarial efficacy. We determined whether daily co-trimoxazole prophylaxis affects the natural development of antibody-mediated immunity to blood-stage Plasmodium falciparum malaria infection. METHODS: Using an enzyme-linked immunosorbent assay, we measured antibodies to 8 Plasmodium falciparum antigens (AMA-1, MSP-119, MSP-3, PfSE, EBA-175RII, GLURP R0, GLURP R2 and CSP) in serum samples from 33 HEU children and 31 HIV-unexposed, uninfected (HUU) children, collected at 6, 12 and 18 months of age. RESULTS: Compared to HIV-uninfected children, HEU children had significantly lower levels of specific IgG against AMA-1 at 6 months (p = 0.001), MSP-119 at 12 months (p = 0.041) and PfSE at 6 months (p = 0.038), 12 months (p = 0.0012) and 18 months (p = 0.0097). No differences in the IgG antibody responses against the rest of the antigens were observed between the two groups at all time points. The breadth of specificity of IgG response was reduced in HEU children compared to HUU children during the follow up period. CONCLUSIONS: Co-trimoxazole prophylaxis seems to reduce IgG antibody responses to P. falciparum blood stage antigens, which could be as a result of a reduction in exposure of those children under this regime. Although antibody responses were regarded as markers of exposure in this study, further studies are required to establish whether these responses are correlated in any way to clinical immunity to malaria.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Infecções por HIV/imunologia , Imunidade Ativa/efeitos dos fármacos , Malária Falciparum/prevenção & controle , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Antibacterianos/farmacologia , Formação de Anticorpos/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Lactente , Malária Falciparum/imunologia , Malaui , Masculino , Combinação Trimetoprima e Sulfametoxazol/farmacologia
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa