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1.
BMC Infect Dis ; 19(Suppl 1): 787, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31526373

RESUMO

BACKGROUND: South Africa (SA) has expanded efforts to reduce mother-to-child transmission of HIV (MTCT) to less than 2% at six weeks after birth and to less than 5% at 18 months postpartum by 2016. Despite improved antiretroviral regimens and coverage between 2001 and 2016, there is little data on infant HIV drug resistance. This paper tracks the prevalence of HIV drug resistance patterns amongst HIV infected infants from three nationally representative studies that assessed the effectiveness of national programs to prevent MTCT (PMTCT). The first study was conducted in 2010 (under the dual therapy PMTCT policy), the second from 2011 to 12 (PMTCT Option A policy) and the third from 2012 to 13 (PMTCT Option A policy). From 2010 to 2013, infant non-nucleoside reverse transcriptase inhibitor (NNRTI) exposure increased from single dose to daily throughout breastfeeding; maternal nucleoside reverse transcriptase inhibitor (NRTI) and NNRTI exposure increased with initiation of NNRTI-and NRTI- containing triple antiretroviral therapy (ART) earlier in gestation and at higher CD4 cell counts. METHODS: Three nationally representative surveys were conducted in 2010, 2011-12 and 2012-13. During the surveys, mothers with known, unknown, or no exposure to antiretrovirals for PMTCT and their infants were included, and MTCT was measured. For this paper, infant dried blood spots (iDBS) from HIV PCR positive infants aged 4-8 weeks, with consent for additional iDBS testing, were analysed for HIV drug resistance at the National Institute of Communicable Diseases (NICD), SA, using an in-house assay validated by the Centers for Disease Control and Prevention (CDC). Total viral nucleic acid was extracted from 2 spots and amplified by nested PCR to generate a ~ 1 kb amplicon that was sequenced using Sanger sequencing technologies. Sequence assembly and editing was performed using RECall v3. RESULTS: Overall, HIV-1 drug resistance was detected in 51% (95% Confidence interval (CI) [45-58%]) of HIV PCR positive infants, 37% (95% CI [28-47%]) in 2010, 64% (95% CI [53-74%]) in 2011 and 63% (95% CI [47-77%]) in 2012 (p < 0.0001), particularly to the NNRTI drug class. Pooled analyses across all three surveys demonstrated that infants whose mothers received ART showed the highest prevalence of resistance (74%); 26% (21/82) of HIV PCR positive infants with no or undocumented antiretroviral drug (ARV) exposure harboured NNRTI resistance. CONCLUSIONS: These data demonstrate increasing NNRTI resistance amongst newly-diagnosed infants in a high HIV prevalence setting where maternal ART coverage increased across the years, starting earlier in gestation and at higher CD4 cell counts. This is worrying as lifelong maternal ART coverage for HIV positive pregnant and lactating women is increasing. Also of concern is that resistant virus was detected in HIV positive infants whose mothers were not exposed to ARVs, raising questions about circulating resistant virus. Numbers in this group were too small to assess trends over the three years.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-1/imunologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Aleitamento Materno , Contagem de Linfócito CD4 , Pré-Escolar , Estudos Transversais , Teste em Amostras de Sangue Seco , Feminino , Infecções por HIV/diagnóstico , Soropositividade para HIV , HIV-1/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Lactação , Mães , Período Pós-Parto , Gravidez , Prevalência , Inibidores da Transcriptase Reversa/uso terapêutico , Autorrelato , África do Sul/epidemiologia
2.
Antivir Ther ; 24(3): 203-210, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30741163

RESUMO

BACKGROUND: Sentinel surveillance of transmitted HIV drug resistance (TDR) among recently infected populations within a country was recommended by the World Health Organization from 2004 to 2015. METHODS: Serum specimens collected as part of the 2010, 2011 and 2012 National Antenatal Sentinel HIV Prevalence Surveys were used to estimate provincial and national TDR prevalence in South Africa. RESULTS: Moderate (5-15%) levels of transmitted non-nucleoside reverse transcriptase inhibitor (NNRTI) drug class resistance were detected in three of five provinces surveyed in 2010 and 2011 (Eastern Cape, Free State and KwaZulu-Natal). Inclusion of all nine of South Africa's provinces in the 2012 survey enabled calculation of a national TDR point prevalence estimate: TDR to the NNRTI drug class was 5.4% (95% CI 3.7, 7.8%), with K103N and V106M being the most frequently detected mutations. TDR estimates for the nucleoside reverse transcriptase inhibitor (NRTI) drug class were 1.1% (95% CI 0.5, 2.4%) and 0.6% (95% CI 0.1, 1.6%) for protease inhibitors (PI). CONCLUSIONS: These data provide national TDR estimates for South Africa in 2012 and indicate that levels of TDR were low to moderate for the NNRTI drug class and low for NRTIs and PIs in the population surveyed.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana/normas , Pessoa de Meia-Idade , Mutação , Vigilância da População , Prevalência , RNA Viral , África do Sul/epidemiologia , Organização Mundial da Saúde , Adulto Jovem
3.
J Virol Methods ; 223: 30-2, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26192603

RESUMO

Paired plasma and dried blood spots (DBS) from 232 South African HIV-infected children initiating antiretroviral therapy (ART) were genotyped for drug resistance mutations, most of who had prior exposure to ART for prevention-of-mother-to-child-transmission. Non-nucleoside reverse transcriptase inhibitor mutations were most commonly detected in both specimen types, particularly Y181C/I and K103N/S. Resistance interpretation concordance was achieved in 97% of pairs with seven children having mutations detected in DBS only. These results validate the preferential use of DBS specimens for HIVDR genotyping in this patient group.


Assuntos
Sangue/virologia , Dessecação , Farmacorresistência Viral , Técnicas de Genotipagem/métodos , Infecções por HIV/virologia , HIV-1/genética , Manejo de Espécimes/métodos , Pré-Escolar , HIV-1/isolamento & purificação , Humanos , Lactente , África do Sul
4.
Virol J ; 9: 164, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22897914

RESUMO

BACKGROUND: Human papillomavirus (HPV) is the aetiological agent for cervical cancer and genital warts. Concurrent HPV and HIV infection in the South African population is high. HIV positive (+) women are often infected with multiple, rare and undetermined HPV types. Data on HPV incidence and genotype distribution are based on commercial HPV detection kits, but these kits may not detect all HPV types in HIV + women. The objectives of this study were to (i) identify the HPV types not detected by commercial genotyping kits present in a cervical specimen from an HIV positive South African woman using next generation sequencing, and (ii) determine if these types were prevalent in a cohort of HIV-infected South African women. METHODS: Total DNA was isolated from 109 cervical specimens from South African HIV + women. A specimen within this cohort representing a complex multiple HPV infection, with 12 HPV genotypes detected by the Roche Linear Array HPV genotyping (LA) kit, was selected for next generation sequencing analysis. All HPV types present in this cervical specimen were identified by Illumina sequencing of the extracted DNA following rolling circle amplification. The prevalence of the HPV types identified by sequencing, but not included in the Roche LA, was then determined in the 109 HIV positive South African women by type-specific PCR. RESULTS: Illumina sequencing identified a total of 16 HPV genotypes in the selected specimen, with four genotypes (HPV-30, 74, 86 and 90) not included in the commercial kit. The prevalence's of HPV-30, 74, 86 and 90 in 109 HIV positive South African women were found to be 14.6%, 12.8%, 4.6% and 8.3% respectively. CONCLUSIONS: Our results indicate that there are HPV types, with substantial prevalence, in HIV positive women not being detected in molecular epidemiology studies using commercial kits. The significance of these types in relation to cervical disease remains to be investigated.


Assuntos
DNA Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Adulto , Colo do Útero/virologia , DNA Viral/química , Feminino , Genótipo , Infecções por HIV/complicações , Humanos , Pessoa de Meia-Idade , Epidemiologia Molecular , Infecções por Papillomavirus/epidemiologia , Prevalência , África do Sul/epidemiologia , Adulto Jovem
5.
BMC Cancer ; 9: 275, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19664216

RESUMO

BACKGROUND: Cervical cancer and infection with human immunodeficiency virus (HIV) are both important public health problems in South Africa (SA). The aim of this study was to determine the prevalence of cervical squamous intraepithelial lesions (SILs), high-risk human papillomavirus (HR-HPV), HPV viral load and HPV genotypes in HIV positive women initiating anti-retroviral (ARV) therapy. METHODS: A cross-sectional survey was conducted at an anti-retroviral (ARV) treatment clinic in Cape Town, SA in 2007. Cervical specimens were taken for cytological analysis and HPV testing. The Digene Hybrid Capture 2 (HC2) test was used to detect HR-HPV. Relative light units (RLU) were used as a measure of HPV viral load. HPV types were determined using the Roche Linear Array HPV Genotyping test. Crude associations with abnormal cytology were tested and multiple logistic regression was used to determine independent risk factors for abnormal cytology. RESULTS: The median age of the 109 participants was 31 years, the median CD4 count was 125/mm3, 66.3% had an abnormal Pap smear, the HR-HPV prevalence was 78.9% (Digene), the median HPV viral load was 181.1 RLU (HC2 positive samples only) and 78.4% had multiple genotypes. Among women with abnormal smears the most prevalent HR-HPV types were HPV types 16, 58 and 51, all with a prevalence of 28.5%. On univariate analysis HR-HPV, multiple HPV types and HPV viral load were significantly associated with the presence of low and high-grade SILs (LSIL/HSIL). The multivariate logistic regression showed that HPV viral load was associated with an increased odds of LSIL/HSIL, odds ratio of 10.7 (95% CI 2.0 - 57.7) for those that were HC2 positive and had a viral load of 181.1 RLU. CONCLUSION: Women initiating ARVs have a high prevalence of abnormal Pap smears and HR-HPV. Our results underscore the need for locally relevant, rigorous screening protocols for the increasing numbers of women accessing ARV therapy so that the benefits of ARVs are not partially offset by an excess risk in cervical cancer.


Assuntos
Alphapapillomavirus/isolamento & purificação , Colo do Útero/patologia , Infecções por HIV/tratamento farmacológico , Infecções por Papillomavirus/epidemiologia , Carga Viral , Adulto , Idoso , Alphapapillomavirus/genética , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Colo do Útero/virologia , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/virologia , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/etiologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , África do Sul/epidemiologia , Adulto Jovem
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