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1.
BMC Health Serv Res ; 21(1): 22, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407442

RESUMO

BACKGROUND: In sub-Saharan Africa, there is dearth of trained laboratorians and strengthened laboratory systems to provide adequate and quality laboratory services for enhanced HIV control. In response to this challenge, in 2007, the African Centre for Integrated Laboratory Training (ACILT) was established in South Africa with a mission to train staffs from countries with high burdens of diseases in skills needed to strengthen sustainable laboratory systems. This study was undertaken to assess the transference of newly gained knowledge and skills to other laboratory staff, and to identify enabling and obstructive factors to their implementation. METHODS: We used Kirkpatrick model to determine training effectiveness by assessing the transference of newly gained knowledge and skills to participant's work environment, along with measuring enabling and obstructive factors. In addition to regular course evaluations at ACILT (pre and post training), in 2015 we sent e-questionnaires to 867 participants in 43 countries for course participation between 2008 and 2014. Diagnostics courses included Viral Load, and systems strengthening included strategic planning and Biosafety and Biosecurity. SAS v9.44 and Excel were used to analyze retrospective de-identified data collected at six months pre and post-training. RESULTS: Of the 867 participants, 203 (23.4%) responded and reported average improvements in accuracy and timeliness in Viral Load programs and to systems strengthening. For Viral Load testing, frequency of corrective action for unsatisfactory proficiency scores improved from 57 to 91%, testing error rates reduced from 12.9% to 4.9%; 88% responders contributed to the first national strategic plan development and 91% developed strategies to mitigate biosafety risks in their institutions. Key enabling factors were team and management support, and key obstructive factors included insufficient resources and staff's resistance to change. CONCLUSIONS: Training at ACILT had a documented positive impact on strengthening the laboratory capacity and laboratory workforce and substantial cost savings. ACILT's investment produced a multiplier effect whereby national laboratory systems, personnel and leadership reaped training benefits. This laboratory training centre with a global clientele contributed to improve existing laboratory services, systems and networks for the HIV epidemic and is now being leveraged for COVID-19 testing that has infected 41,332,899 people globally.


Assuntos
Epidemias/prevenção & controle , Infecções por HIV/prevenção & controle , Laboratórios/organização & administração , Pessoal de Laboratório/educação , África Subsaariana/epidemiologia , Teste para COVID-19 , Serviços de Laboratório Clínico , Infecções por HIV/epidemiologia , Teste de HIV , Pesquisa sobre Serviços de Saúde , Humanos , Estudos Retrospectivos
2.
MMWR Morb Mortal Wkly Rep ; 65(46): 1285-1290, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27880749

RESUMO

Pediatric human immunodeficiency virus (HIV) infection remains an important public health issue in resource-limited settings. In 2015, 1.4 million children aged <15 years were estimated to be living with HIV (including 170,000 infants born in 2015), with the vast majority living in sub-Saharan Africa (1). In 2014, 150,000 children died from HIV-related causes worldwide (2). Access to timely HIV diagnosis and treatment for HIV-infected infants reduces HIV-associated mortality, which is approximately 50% by age 2 years without treatment (3). Since 2011, the annual number of HIV-infected children has declined by 50%. Despite this gain, in 2014, only 42% of HIV-exposed infants received a diagnostic test for HIV (2), and in 2015, only 51% of children living with HIV received antiretroviral therapy (1). Access to services for early infant diagnosis of HIV (which includes access to testing for HIV-exposed infants and clinical diagnosis of HIV-infected infants) is critical for reducing HIV-associated mortality in children aged <15 years. Using data collected from seven countries supported by the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), progress in the provision of HIV testing services for early infant diagnosis was assessed. During 2011-2015, the total number of HIV diagnostic tests performed among HIV-exposed infants within 6 weeks after birth (tests for early infant diagnosis of HIV), as recommended by the World Health Organization (WHO) increased in all seven countries (Cote d'Ivoire, the Democratic Republic of the Congo, Haiti, Malawi, South Africa, Uganda, and Zambia); however, in 2015, the rate of testing for early infant diagnosis among HIV-exposed infants was <50% in five countries. HIV positivity among those tested declined in all seven countries, with three countries (Cote d'Ivoire, the Democratic Republic of the Congo, and Uganda) reporting >50% decline. The most common challenges for access to testing for early infant diagnosis included difficulties in specimen transport, long turnaround time between specimen collection and receipt of results, and limitations in supply chain management. Further reductions in HIV mortality in children can be achieved through continued expansion and improvement of services for early infant diagnosis in PEPFAR-supported countries, including initiatives targeted to reach HIV-exposed infants, ensure access to programs for early infant diagnosis of HIV, and facilitate prompt linkage to treatment for children diagnosed with HIV infection.


Assuntos
Diagnóstico Precoce , Infecções por HIV/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , África Subsaariana , Região do Caribe , Feminino , Infecções por HIV/transmissão , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Gravidez
3.
BMC Public Health ; 15: 1149, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26588902

RESUMO

BACKGROUND: South Africa has over 6,000,000 HIV infected individuals and the province of KwaZulu-Natal (KZN) is the most severely affected. As public health initiatives to better control the HIV epidemic are implemented, timely, detailed and robust surveillance data are needed to monitor, evaluate and inform the programmatic interventions and policies over time. We describe the rationale and design of the HIV Incidence Provincial Surveillance System (HIPSS) to monitor HIV prevalence and incidence. METHODS/DESIGN: The household-based survey will include a sample of men and women from two sub-districts of the uMgungundlovu municipality (Vulindlela and the Greater Edendale) of KZN, South Africa. The study is designed as two sequential cross-sectional surveys of 10,000 randomly selected individuals aged 15-49 years to be conducted one year apart. From the cross sectional surveys, two sequential cohorts of HIV negative individuals aged 15-35 years will be followed-up one year later to measure the primary outcome of HIV incidence. Secondary outcomes include the laboratory measurements for pulmonary tuberculosis, sexually transmitted infections and evaluating tests for estimating population-level HIV incidence. Antiretroviral therapy (ART) access, HIV-1 RNA viral load, and CD4 cell counts in HIV positive individuals will assess the effectiveness of the HIV treatment cascade. Household and individual-level socio-demographic characteristics, exposure to HIV programmatic interventions and risk behaviours will be assessed as predictors of HIV incidence. The incidence rate ratio of the two cohorts will be calculated to quantify the change in HIV incidence between consecutive samples. In anticipation of better availability of population-level HIV prevention and treatment programmes leading to decreases in HIV incidence, the sample size provides 84% power to detect a reduction of 30% in the HIV incidence rate between surveys. DISCUSSION: The results from HIPSS will provide critical data regarding HIV prevalence and incidence in this community and will establish whether HIV prevention and treatment efforts in a "real world", non-trial setting have an impact on HIV incidence at a population level. Importantly, the study design and methods will inform future methods for HIV surveillance.


Assuntos
Características da Família , Infecções por HIV/epidemiologia , HIV-1 , Vigilância da População/métodos , Características de Residência , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Projetos de Pesquisa , Assunção de Riscos , África do Sul/epidemiologia , Carga Viral , Adulto Jovem
4.
Lancet HIV ; 5(8): e427-e437, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30021700

RESUMO

BACKGROUND: In high HIV burden settings, maximising the coverage of prevention strategies is crucial to achieving epidemic control. However, little is known about the reach and effect of these strategies in some communities. METHODS: We did a cross-sectional community survey in the adjacent Greater Edendale and Vulindlela areas in the uMgungundlovu district, KwaZulu-Natal, South Africa. Using a multistage cluster sampling method, we randomly selected enumeration areas, households, and individuals. One household member (aged 15-49 years) selected at random was invited for survey participation. After obtaining consent, questionnaires were administered to obtain sociodemographic, psychosocial, and behavioural information, and exposure to HIV prevention and treatment programmes. Clinical samples were collected for laboratory measurements. Statistical analyses were done accounting for multilevel sampling and weighted to represent the population. A multivariable logistic regression model assessed factors associated with HIV infection. FINDINGS: Between June 11, 2014, and June 22, 2015, we enrolled 9812 individuals. The population-weighted HIV prevalence was 36·3% (95% CI 34·8-37·8, 3969 of 9812); 44·1% (42·3-45·9, 2955 of 6265) in women and 28·0% (25·9-30·1, 1014 of 3547) in men (p<0·0001). HIV prevalence in women aged 15-24 years was 22·3% (20·2-24·4, 567 of 2224) compared with 7·6% (6·0-9·3, 124 of 1472; p<0·0001) in men of the same age. Prevalence peaked at 66·4% (61·7-71·2, 517 of 760) in women aged 35-39 years and 59·6% (53·0-66·3, 183 of 320) in men aged 40-44 years. Consistent condom use in the last 12 months was 26·5% (24·1-28·8, 593 of 2356) in men and 22·7% (20·9-24·4, 994 of 4350) in women (p=0·0033); 35·7% (33·4-37·9, 1695 of 5447) of women's male partners and 31·9% (29·5-34·3, 1102 of 3547) of men were medically circumcised (p<0·0001), and 45·6% (42·9-48·2, 1251 of 2955) of women and 36·7% (32·3-41·2, 341 of 1014) of men reported antiretroviral therapy (ART) use (p=0·0003). HIV viral suppression was achieved in 54·8% (52·0-57·5, 1574 of 2955) of women and 41·9% (37·1-46·7, 401 of 1014) of men (p<0·0001), and 87·2% (84·6-89·8, 1086 of 1251) of women and 83·9% (78·5-89·3, 284 of 341; p=0·3670) of men on ART. Age, incomplete secondary schooling, being single, having more than one lifetime sex partner (women), sexually transmitted infections, and not being medically circumcised were associated with HIV-positive status. INTERPRETATION: The HIV burden in specific age groups, the suboptimal differential coverage, and uptake of HIV prevention strategies justifies a location-based approach to surveillance with finer disaggregation by age and sex. Intensified and customised approaches to seek, identify, and link individuals to HIV services are crucial to achieving epidemic control in this community. FUNDING: The President's Emergency Plan for AIDS Relief through the Centers for Disease Control and Prevention.


Assuntos
Características da Família , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Saúde Pública , Adolescente , Adulto , Contagem de Linfócito CD4 , Estudos Transversais , Epidemias , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco , Parceiros Sexuais , África do Sul/epidemiologia , Inquéritos e Questionários , Carga Viral , Adulto Jovem
5.
J Int AIDS Soc ; 20(Suppl 6): 21753, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28872274

RESUMO

INTRODUCTION: We describe the overall accuracy and performance of a serial rapid HIV testing algorithm used in community-based HIV testing in the context of a population-based household survey conducted in two sub-districts of uMgungundlovu district, KwaZulu-Natal, South Africa, against reference fourth-generation HIV-1/2 antibody and p24 antigen combination immunoassays. We discuss implications of the findings on rapid HIV testing programmes. METHODS: Cross-sectional design: Following enrolment into the survey, questionnaires were administered to eligible and consenting participants in order to obtain demographic and HIV-related data. Peripheral blood samples were collected for HIV-related testing. Participants were offered community-based HIV testing in the home by trained field workers using a serial algorithm with two rapid diagnostic tests (RDTs) in series. In the laboratory, reference HIV testing was conducted using two fourth-generation immunoassays with all positives in the confirmatory test considered true positives. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value and false-positive and false-negative rates were determined. RESULTS: Of 10,236 individuals enrolled in the survey, 3740 were tested in the home (median age 24 years (interquartile range 19-31 years), 42.1% males and HIV positivity on RDT algorithm 8.0%). From those tested, 3729 (99.7%) had a definitive RDT result as well as a laboratory immunoassay result. The overall accuracy of the RDT when compared to the fourth-generation immunoassays was 98.8% (95% confidence interval (CI) 98.5-99.2). The sensitivity, specificity, positive predictive value and negative predictive value were 91.1% (95% CI 87.5-93.7), 99.9% (95% CI 99.8-100), 99.3% (95% CI 97.4-99.8) and 99.1% (95% CI 98.8-99.4) respectively. The false-positive and false-negative rates were 0.06% (95% CI 0.01-0.24) and 8.9% (95% CI 6.3-12.53). Compared to true positives, false negatives were more likely to be recently infected on limited antigen avidity assay and to report antiretroviral therapy (ART) use. CONCLUSIONS: The overall accuracy of the RDT algorithm was high. However, there were few false positives, and the sensitivity was lower than expected with high false negatives, despite implementation of quality assurance measures. False negatives were associated with recent (early) infection and ART exposure. The RDT algorithm was able to correctly identify the majority of HIV infections in community-based HIV testing. Messaging on the potential for false positives and false negatives should be included in these programmes.


Assuntos
Erros de Diagnóstico/estatística & dados numéricos , Infecções por HIV/diagnóstico , HIV-1/isolamento & purificação , Sorodiagnóstico da AIDS , Adulto , Algoritmos , Estudos Transversais , Feminino , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , Humanos , Masculino , Programas de Rastreamento , Sensibilidade e Especificidade , África do Sul , Inquéritos e Questionários , Adulto Jovem
6.
Medicine (Baltimore) ; 96(28): e7391, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28700474

RESUMO

We describe the accuracy of serial rapid HIV testing among men who have sex with men (MSM) in South Africa and discuss the implications for HIV testing and prevention.This was a cross-sectional survey conducted at five stand-alone facilities from five provinces.Demographic, behavioral, and clinical data were collected. Dried blood spots were obtained for HIV-related testing. Participants were offered rapid HIV testing using 2 rapid diagnostic tests (RDTs) in series. In the laboratory, reference HIV testing was conducted using a third-generation enzyme immunoassay (EIA) and a fourth-generation EIA as confirmatory. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false-positive, and false-negative rates were determined.Between August 2015 and July 2016, 2503 participants were enrolled. Of these, 2343 were tested by RDT on site with a further 2137 (91.2%) having definitive results on both RDT and EIA. Sensitivity, specificity, positive predictive value, negative predictive value, false-positive rates, and false-negative rates were 92.6% [95% confidence interval (95% CI) 89.6-94.8], 99.4% (95% CI 98.9-99.7), 97.4% (95% CI 95.2-98.6), 98.3% (95% CI 97.6-98.8), 0.6% (95% CI 0.3-1.1), and 7.4% (95% CI 5.2-10.4), respectively. False negatives were similar to true positives with respect to virological profiles.Overall accuracy of the RDT algorithm was high, but sensitivity was lower than expected. Post-HIV test counseling should include discussions of possible false-negative results and the need for retesting among HIV negatives.


Assuntos
Sorodiagnóstico da AIDS , Algoritmos , Infecções por HIV/sangue , Infecções por HIV/diagnóstico , Homossexualidade Masculina , Inquéritos e Questionários , Adulto , Estudos Transversais , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Técnicas Imunoenzimáticas , Masculino , Controle de Qualidade , Sensibilidade e Especificidade , Fatores Socioeconômicos , África do Sul , Adulto Jovem
7.
J Ind Microbiol Biotechnol ; 35(6): 587-94, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18239946

RESUMO

The effects of cultivation pH and agitation rate on growth and extracellular xylanase production by Aspergillus oryzae NRRL 3485 were investigated in bioreactor cultures using spent sulphite liquor (SSL) and oats spelts xylan as respective carbon substrates. Xylanase production by this fungus was greatly affected by the culture pH, with pH 7.5 resulting in a high extracellular xylanase activity in the SSL-based medium as well as in a complex medium with xylan as carbon substrate. This effect, therefore, was not solely due to growth inhibition at the lower pH values by the acetic acid in the SSL. The xylanase activity in the SSL medium peaked at 199 U ml(-1) at pH 7.5 with a corresponding maximum specific growth rate of 0.39 h(-1). By contrast, the maximum extracellular beta-xylosidase activity pf 0.36 U ml(-1) was recorded at pH 4.0. Three low molecular weight xylanase isozymes were secreted at all pH values within the range of pH 4-8, whereas cellulase activity on both carbon substrates was negligible. Impeller tip velocities within the range of 1.56-3.12 m s(-1) had no marked effect, either on the xylanase activity, or on the maximum volumetric rate of xylanase production. These results also demonstrated that SSL constituted a suitable carbon feedstock as well as inducer for xylanase production in aerobic submerged culture by this strain of A. oryzae.


Assuntos
Aspergillus oryzae/enzimologia , Aspergillus oryzae/crescimento & desenvolvimento , Endo-1,4-beta-Xilanases/biossíntese , Sulfitos/metabolismo , Movimentos da Água , Aspergillus oryzae/metabolismo , Reatores Biológicos , Celulase/metabolismo , Meios de Cultura/química , Endo-1,4-beta-Xilanases/metabolismo , Concentração de Íons de Hidrogênio , Xilanos/metabolismo , Xilosidases/metabolismo
8.
Appl Microbiol Biotechnol ; 69(1): 71-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15944854

RESUMO

Xylanase production by seven fungal strains was investigated using concentrated spent sulphite liquor (SSLc), xylan and D: -xylose as carbon substrates. An SSLc-based medium induced xylanase production at varying levels in all of these strains, with Aspergillus oryzae NRRL 3485 and Aspergillus phoenicis ATCC 13157 yielding activities of 164 and 146 U ml(-1), respectively; these values were higher than those obtained on xylan or D: -xylose with the same fungal strains. The highest xylanase activity of 322 U ml(-1) was obtained with Aspergillus foetidus ATCC 14916 on xylan. Electrophoretic and zymogram analysis indicated three xylanases from A. oryzae with molecular weights of approximately 32, 22 and 19 kDa, whereas A. phoenicis produced two xylanases with molecular weights of about 25 and 21 kDa. Crude xylanase preparations from these A. oryzae and A. phoenicis strains exhibited optimal activities at pH 6.5 and 5.0 and at 65 and 55 degrees C, respectively. The A. oryzae xylanolytic activity was stable at 50 degrees C over the pH range 4.5-10. The crude xylanase preparations from these A. oryzae and A. phoenicis strains had negligible cellulase activity, and their application in the biobleaching of hardwood pulp reduced chlorine dioxide consumption by 20-30% without sacrificing brightness.


Assuntos
Endo-1,4-beta-Xilanases/biossíntese , Fungos/enzimologia , Fungos/metabolismo , Resíduos Industriais , Sulfitos/metabolismo , Aspergillus/enzimologia , Aspergillus/metabolismo , Proteínas de Bactérias/análise , Proteínas de Bactérias/metabolismo , Celulase/análise , Eletroforese , Endo-1,4-beta-Xilanases/isolamento & purificação , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Peso Molecular , Especificidade por Substrato , Temperatura , Xilanos/metabolismo , Xilose/metabolismo
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