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1.
Front Microbiol ; 15: 1342862, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784816

RESUMO

Aim: This study aimed to determine the kinetics of occult hepatitis B virus infections (OBI) among people with HIV (PWH). Methods: The study used archived plasma samples from longitudinal HIV natural history studies. We identified new OBI cases and assessed risk factors for OBI using Cox proportional hazards regression analysis. Results: At baseline, 8 of 382 [(2.1%) (95% CI: 1.06-4.1)] samples tested positive for hepatitis B surface antigen (HBsAg+). Of the 374 HBsAg-negative samples, 76 had sufficient sample volume for HBV DNA screening. OBI positivity (OBI+) at baseline was reported in 11 of 76 [14.7 95% CI (8.3-24.1)] HBsAg-negative (HBsAg-) participants. Baseline HBsAg-negative samples with sufficient follow-up samples (n = 90) were used for analysis of newly identified OBI cases. Participants contributed 129.74 person-years to the study and were followed for a median of 1.02 years (IQR: 1.00-2.00). Cumulatively, there were 34 newly identified OBI cases from the 90 participants, at the rate of 26.2/100 person-years (95% CI: 18.7-36.7). Newly identified OBI cases were more common among men than women (61.1% vs. 31.9%) and among participants with CD4+ T-cell counts ≤450 cells/mL (p-value = 0.02). Most of the newly identified OBI cases [55.9% (19/34)] were possible reactivations as they were previously HBV core antibody positive. Conclusion: There was a high rate of newly identified OBI among young PWH in Botswana, especially in men and in participants with lower CD4+ T-cell counts. OBI screening in PWH should be considered because of the risk of transmission, possible reactivation, and risk factors for the development of chronic liver disease, including hepatocellular carcinoma.

2.
Front Microbiol ; 15: 1338191, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476948

RESUMO

Background: Approximately 30,000 non-citizens are living with HIV in Botswana, all of whom as of 2020 are eligible to receive free antiretroviral treatment (ART) within the country. We assessed the prevalence of HIV-1 mutational profiles [pre-treatment drug resistance (PDR) and acquired drug resistance (ADR)] among treatment-experienced (TE) and treatment-naïve (TN) non-citizens living with HIV in Botswana. Methods: A total of 152 non-citizens living with HIV were enrolled from a migrant HIV clinic at Independence Surgery, a private practice in Botswana from 2019-2021. Viral RNA isolated from plasma samples were genotyped for HIV drug resistance (HIVDR) using Sanger sequencing. Major known HIV drug resistance mutations (DRMs) in the pol region were determined using the Stanford HIV Drug Resistance Database. The proportions of HIV DRMs amongst TE and TN non-citizens were estimated with 95% confidence intervals (95% CI) and compared between the two groups. Results: A total of 60/152 (39.5%) participants had a detectable viral load (VL) >40 copies/mL and these were included in the subsequent analyses. The median age at enrollment was 43 years (Q1, Q3: 38-48). Among individuals with VL > 40 copies/mL, 60% (36/60) were treatment-experienced with 53% (19/36) of them on Atripla. Genotyping had a 62% (37/60) success rate - 24 were TE, and 13 were TN. A total of 29 participants (78.4, 95% CI: 0.12-0.35) had major HIV DRMs, including at least one non-nucleoside reverse transcriptase inhibitor (NNRTI) associated DRM. In TE individuals, ADR to any antiretroviral drug was 83.3% (20/24), while for PDR was 69.2% (9/13). The most frequent DRMs were nucleoside reverse transcriptase inhibitors (NRTIs) M184V (62.1%, 18/29), NNRTIs V106M (41.4%, 12/29), and K103N (34.4%, 10/29). No integrase strand transfer inhibitor-associated DRMs were reported. Conclusion: We report high rates of PDR and ADR in ART-experienced and ART-naïve non-citizens, respectively, in Botswana. Given the uncertainty of time of HIV acquisition and treatment adherence levels in this population, routine HIV-1C VL monitoring coupled with HIVDR genotyping is crucial for long-term ART success.

3.
Int J Infect Dis ; 138: 91-96, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37952911

RESUMO

We investigated intra-host genetic evolution using two SARS-CoV-2 isolates from a fully vaccinated (primary schedule x2 doses of AstraZeneca plus a booster of Pfizer), >70-year-old woman with a history of lymphoma and hypertension who presented a SARS-CoV-2 infection for 3 weeks prior to death due to COVID-19. Two full genome sequences were determined from samples taken 13 days apart with both belonging to Pango lineage FL.2: the first detection of this Omicron sub-variant in Botswana. FL.2 is a sub-lineage of XBB.1.9.1. The repertoire of mutations and minority variants in the Spike protein differed between the two time points. Notably, we also observed deletions within the ORF1a and Membrane proteins; both regions are associated with high T-cell epitope density. The internal milieu of immune-suppressed individuals may accelerate SARS-CoV-2 evolution; hence, close monitoring is warranted.


Assuntos
COVID-19 , Feminino , Humanos , Idoso , SARS-CoV-2/genética , Botsuana , Infecções Irruptivas
4.
Infect Agent Cancer ; 18(1): 29, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165397

RESUMO

BACKGROUND: Low- and middle-income countries (LMICs) account for nearly 85% of the global cervical cancer burden, yet have the least access to high-performance screening. International guidelines recommend human papillomavirus testing (HPV) as primary screening, yet implementation is inhibited by the cost of HPV testing. Atila AmpFire® HPV Assay (AmpFire) is both affordable and easy to use, and offers individual genotyping. The objective of this study was to compare the performance of the AmpFire HPV assay to the Xpert® HPV assay in detection of both HPV and clinically significant cervical disease. METHODS: We utilized stored cervical specimens from a prospective cohort study of women living with human immunodeficiency virus (HIV) in Botswana conducted from May to July 2018. Positive and negative percent agreement was calculated for the AmpFire and Xpert assays, as was detection of high-grade cervical dysplasia. RESULTS: 63 stored cervical specimens had detectable DNA after thawing and were included in the analysis. The positive percent agreement was 91.2% (95%CI 76.3-98.1) and negative percent agreement was 79.3% (95% CI 60.3-92.0). Six cases positive by AmpFire but negative by Xpert were HPV genotypes 35, 52 (n = 2), 58, 68, and co-infection with HPV 45 and 68. Both Xpert and AmpFire assays detected HPV in all 10 samples of women who had high-grade cervical dysplasia. CONCLUSIONS: The AmpFire HPV assay demonstrated excellent analytic performance in both detection of HPV and clinically significant cervical disease. AmpFire HPV is a promising option to increase access to affordable, type-specific HPV screening for cervical cancer in LMICs.

5.
Res Sq ; 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36909533

RESUMO

Background: Low- and middle-income countries (LMICs) account for nearly 85% of the global cervical cancer burden, yet have the least access to high-performance screening. International guidelines recommend human papillomavirus testing (HPV) as primary screening, yet implementation is inhibited by the cost of HPV testing.Atila AmpFire HPV Assay (AmpFire) is both affordable and easy to use, and offers individual genotyping. The objective of this study was to compare the performance of the AmpFire HPV assay to the Xpert HPV assay in detection of both HPV and clinically significant cervical disease. Methods: We utilized stored cervical specimens from a prospective cohortstudy of women living with human immunodeficiency virus (HIV) in Botswana conducted from May to July 2018. Positive and negative percent agreement was calculated for the AmpFire and Xpert assays, as was detection of high-grade cervical dysplasia. Results : 63 stored cervical specimens haddetectable DNA after thawing and were included in the analysis. The positive percent agreement was 91.2% (95%CI: 76.3-98.1) and negative percent agreement was 79.3% (95% CI: 60.3-92.0). Six cases positive by AmpFire but negative by Xpert were HPV genotypes 35, 52 (n=2), 58, 68, and co-infection with HPV 45 and 68. Both Xpert and AmpFire assays detected HPV in all 10 samples of women who had high-grade cervical dysplasia. Conclusions : The AmpFire HPV assay demonstrated excellent analytic performance in both detection of HPV and clinically significant cervical disease. AmpFire HPV is a promising option to increase access to affordable, type-specific HPV screening for cervical cancer in LMICs.

6.
J Antimicrob Chemother ; 78(1): 180-184, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36322466

RESUMO

OBJECTIVES: We compared the patterns of HIV-1 drug resistance mutations between the CSF and plasma of individuals with HIV-associated cryptococcal meningitis. METHODS: This is a cross-sectional study of archived CSF and plasma samples collected from ART-exposed participants recruited in the Phase 3 AmBisome Therapy Induction Optimisation randomized controlled trial (ISRCTN72509687) conducted in Botswana between 2018 and 2021. HIV-1 RT and protease genes were genotyped using next-generation sequencing and HIV-1 drug resistance mutations were compared between the CSF and plasma compartments stratified by thresholds of ≥20% and <20%. RESULTS: Overall, 66.7% (16/24) of participants had at least one HIV-1 drug resistance mutation in the CSF and/or plasma. A total of 15/22 (68.2%) participants had HIV-1 drug resistance mutations at ≥20% threshold in the plasma and of those, 11 (73.3%) had been on ART longer than 6 months. HIV-1 drug resistance mutations were highly concordant between the CSF and plasma at ≥20% threshold despite a substantial number of individuals experiencing CSF viral escape and with only 54.5% with CSF WBC count ≥20 cells/mm3. Minority HIV-1 drug resistance mutations were detected in 20.8% (5/24) of participants. There were no mutations in the CSF that were not detected in the plasma. CONCLUSIONS: There was high concordance in HIV-1 drug resistance mutations in the CSF and plasma, suggesting intercompartmental mixing and possibly a lack of compartmentalization. Some individuals harboured minority HIV-1 drug resistance mutations, demonstrating the need to employ more sensitive genotyping methods such as next-generation sequencing for the detection of low-abundance mutations.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Meningite Criptocócica , Humanos , HIV-1/genética , Meningite Criptocócica/tratamento farmacológico , Meningite Criptocócica/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Botsuana/epidemiologia , Estudos Transversais , Farmacorresistência Viral/genética , Soropositividade para HIV/tratamento farmacológico , Carga Viral , Fármacos Anti-HIV/uso terapêutico
7.
BMC Infect Dis ; 22(1): 95, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35086475

RESUMO

BACKGROUND: The variation of human papillomavirus (HPV) genotypes shapes the risks of cervical cancer and these variations are not well defined in Africa. Nucleotide changes within the L1 gene, nucleotide variability, and phylogeny were explored in relation to HIV in samples from Botswana and Kenya. METHODS: A total of 98 HPV-positive cervical samples were sequenced to identify different HPV variants. Phylogenetic inferences were used to determine HPV genotypes and investigate the clustering of sequences between women living with HIV (WLWHIV) and -women not living with HIV (WNLWHIV). RESULTS: Out of 98 generated sequences, 83.7% (82/98) participants had high-risk (HR) HPV genotypes while 16.3% (16/98) had low-risk (LR) HPV genotypes. Among participants with HR-HPV genotypes, 47.6% (39/82) were coinfected with HIV. The prevalence of HR-HPV genotypes was statistically higher in the Botswana population compared to Kenya (p-value < 0.001). Multiple amino acid mutations were identified in both countries. Genetic diversity differed considerably among WLWHIV and WNLWHIV. The mean pairwise distances between HPV-16 between HIV and HIV/HPV as well as for HPV-18 were statistically significant. Six (6) new deleterious mutations were identified in the HPV genotypes based on the sequencing of the L1 region, HPV-16 (L441P, S343P), HPV-18 (S424P), HPV-45 (Q366H, Y365F), and HPV-84 (F458L). The majority of the patients with these mutations were co-infected with HIV. CONCLUSIONS: Genomic diversity and different genomic variants of HPV sequences were demonstrated. Candidate novel mutations within the L1 gene were identified in both countries which can be further investigated using functional assays.


Assuntos
Alphapapillomavirus , Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Botsuana/epidemiologia , Feminino , Variação Genética , Genótipo , HIV , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Quênia/epidemiologia , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Filogenia , Neoplasias do Colo do Útero/epidemiologia
8.
Anal Bioanal Chem ; 413(25): 6401-6412, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34557941

RESUMO

We demonstrate the suitability of a fast, green, easy-to-perform, and modified sample extraction procedure, i.e., dispersive liquid-liquid microextraction (DLLME) for the determination of efavirenz (EFV) in human plasma. Data acquisition was done by gas chromatography-mass spectrometry (GC-MS) in the selected ion monitoring (SIM) mode. The simplicity of the method lies in, among others, the avoidance of the use of large organic solvent volumes as mobile phases and non-volatile buffers that tend to block the plumbing in high-performance liquid chromatography (HPLC). Chromatographic and mass spectral parameters were optimized using bovine whole blood for matrix matching due to insufficient human plasma. Method validation was accomplished using the United States Food and Drug Administration (USFDA) 2018 guidelines. The calibration curve was linear with a dynamic range of 0.10-2.0 µg/mL and an R2 value of 0.9998. The within-run accuracy and precision were both less than 20% at the lower limit of quantification (LLOQ) spike level. The LLOQ was 0.027 µg/mL which compared well with some values but was also orders of magnitude better than others reported in the literature. The percent recovery was 91.5% at the LLOQ spike level. The DLLME technique was applied in human plasma samples from patients who were on treatment with EFV. The human plasma samples gave concentrations of EFV ranging between 0.14-1.00 µg/mL with three samples out of seven showing concentrations that fell within or close to the recommended therapeutic range.


Assuntos
Alcinos/sangue , Benzoxazinas/sangue , Ciclopropanos/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Inibidores da Transcriptase Reversa/sangue , Alcinos/química , Antibacterianos/sangue , Antibacterianos/química , Benzoxazinas/química , Ciclopropanos/química , Humanos , Limite de Detecção , Metronidazol/sangue , Metronidazol/química , Estrutura Molecular
9.
Pathogens ; 10(8)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34451492

RESUMO

Dolutegravir (DTG) is a potent anti-HIV drug that is used to treat HIV globally. There have been reports of mutations in the HIV-1 3'-polypurine tract (3'PPT) of the nef gene, contributing to DTG failure; however, there are limited 'real-world' data on this. In addition, there is a knowledge gap on the variability of 3'PPT residues in patients receiving combination antiretroviral therapy (cART) with and without viral load (VL) suppression. HIV-1 subtype C (HIV-1C) whole-genome sequences from cART naïve and experienced individuals were generated using next-generation sequencing. The nef gene sequences were trimmed from the generated whole-genome sequences using standard bioinformatics tools. In addition, we generated separate integrase and nef gene sequences by Sanger sequencing of plasma samples from individuals with virologic failure (VF) while on a DTG/raltegravir (RAL)-based cART. Analysis of 3'PPT residues was performed, and comparison of proportions computed using Pearson's chi-square test with p-values < 0.05 was considered statistically significant. A total of 6009 HIV-1C full genome sequences were generated and had a median log10 HIV-1 VL (Q1, Q3) copies/mL of 1.60 (1.60, 2.60). A total of 12 matching integrase and nef gene sequences from therapy-experienced participants failing DTG/ RAL-based cART were generated. HIV-1C 3'PPT nef gene sequences from therapy-experienced patients failing DTG cART (n = 12), cART naïve individuals (n = 1263), and individuals on cART with and without virological suppression (n = 4696) all had a highly conserved 3'PPT motif with no statistically significant differences identified. Our study confirms the high conservation of the HIV-1 nef gene 3'PPT motif in 'real-world' patients and showed no differences in the motif according to VL suppression or INSTI-based cART failure. Future studies should explore other HIV-1 regions outside of the pol gene for associations with DTG failure.

10.
Front Oncol ; 11: 560296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33718129

RESUMO

Background: Epidemics of human immunodeficiency virus (HIV) and cervical cancer are interconnected. DNA hypermethylation of host genes' promoter in cervical lesions has also been recognized as a contributor to cervical cancer progression. Methods: For this purpose we analyzed promoter methylation of four tumor suppressor genes (RARB, CADM1, DAPK1 and PAX1) and explored their possible association with cervical cancer in Botswana among women of known HIV status. Overall, 228 cervical specimens (128 cervical cancers and 100 non-cancer subjects) were used. Yates-corrected chi-square test and Fisher's exact test were used to explore the association of promoter methylation for each host gene and cancer status. Subsequently, a logistic regression analysis was performed to find which factors, HIV status, high risk-HPV genotypes, patient's age and promoter methylation, were associated with the following dependent variables: cancer status, cervical cancer stage and promoter methylation rate. Results: In patients with cervical cancer the rate of promoter methylation observed was greater than 64% in all the genes studied. Analysis also showed a higher risk of cervical cancer according to the increased number of methylated promoter genes (OR = 6.20; 95% CI: 3.66-10.51; P < 0.001). RARB methylation showed the strongest association with cervical cancer compared to other genes (OR = 15.25; 95% CI: 6.06-40.0; P < 0.001). Cervical cancer and promoter methylation of RARB and DAPK1 genes were associated with increasing age (OR = 1.12; 95% CI: 1.01-1.26; P = 0.037 and OR = 1.05; 95% CI: 1.00-1.10; P = 0.040). The presence of epigenetic changes at those genes appeared to be independent of HIV status among subjects with cervical cancer. Moreover, we found that cervical cancer stage was influenced by RARB (χ2= 7.32; P = 0.002) and CADM1 (χ2=12.68; P = 0.013) hypermethylation, and HIV status (χ2= 19.93; P = 0.001). Conclusion: This study confirms the association between invasive cervical cancer and promoter gene methylation of tumor suppressing genes at the site of cancer. HIV infection did not show any association to methylation changes in this group of cervical cancer patients from Botswana. Further studies are needed to better understand the role of HIV in methylation of host genes among cancer subjects leading to cervical cancer progression.

11.
Viruses ; 12(12)2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33297399

RESUMO

HIV-1 compartmentalization in reservoir sites remains a barrier to complete HIV eradication. It is unclear whether there is variation in HIV-1 env and gag between cerebrospinal fluid (CSF) and plasma of individuals with HIV-associated cryptococcal meningitis (CM). We compared HIV-1 env characteristics and the gag cytotoxic T-lymphocyte (CTL) escape mutations from CSF and plasma samples. Employing population-based Sanger sequencing, we sequenced HIV-1 env from CSF of 25 patients and plasma of 26 patients. For gag, 15 CSF and 21 plasma samples were successfully sequenced. Of these, 18 and 9 were paired env and gag CSF/plasma samples, respectively. There was no statistically significant difference in the proportion of CCR5-using strains in the CSF and plasma, (p = 0.50). Discordant CSF/plasma virus co-receptor use was found in 2/18 pairs (11.1%). The polymorphisms in the HIV-1 V3 loop were concordant between the two compartments. From the HIV-1 gag sequences, three pairs had discordant CTL escape mutations in three different epitopes of the nine analyzed. These findings suggest little variation in the HIV-1 env between plasma and CSF and that the CCR5-using strains predominate in both compartments. HIV-1 gag CTL escape mutations also displayed little variation in CSF and plasma suggesting similar CTL selective pressure.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/metabolismo , Infecções por HIV/complicações , Meningite Criptocócica/etiologia , Meningite Criptocócica/metabolismo , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/líquido cefalorraquidiano , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Adulto , Sequência de Aminoácidos , Substituição de Aminoácidos , Botsuana , Contagem de Linfócito CD4 , Estudos Transversais , Suscetibilidade a Doenças , Feminino , Infecções por HIV/virologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Meningite Criptocócica/sangue , Meningite Criptocócica/líquido cefalorraquidiano , Pessoa de Meia-Idade , Mutação , RNA Viral , Carga Viral , Produtos do Gene env do Vírus da Imunodeficiência Humana/sangue , Produtos do Gene env do Vírus da Imunodeficiência Humana/líquido cefalorraquidiano , Produtos do Gene gag do Vírus da Imunodeficiência Humana/sangue , Produtos do Gene gag do Vírus da Imunodeficiência Humana/líquido cefalorraquidiano
12.
Medicine (Baltimore) ; 99(41): e22606, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031315

RESUMO

To determine effects of cryptococcal meningitis (CM) on human immunodeficiency virus (HIV)-1C cerebrospinal fluid (CSF) viral escape, CSF/plasma viral discordance, and drug resistance mutation (DRM) discordance between CSF and plasma compartments, we compared CSF and plasma viral load (VL) and DRMs in individuals with HIV-associated CM in Botswana.This cross-sectional study utilized 45 paired CSF/plasma samples from participants in a CM treatment trial (2014-2016). HIV-1 VL was determined and HIV-1 protease and reverse transcriptase genotyping performed. DRMs were determined using the Stanford HIV database. CSF viral escape was defined as HIV-1 ribonucleic acid ≥0.5 log10 higher in CSF than plasma and VL discordance as CSF VL > plasma VL.HIV-1 VL was successfully measured in 39/45 pairs, with insufficient sample volume in 6; 34/39 (87.2%) participants had detectable HIV-1 in plasma and CSF, median 5.1 (interquartile range: 4.7-5.7) and 4.6 (interquartile range:3.7-4.9) log10 copies/mL, respectively (P≤.001). CSF viral escape was present in 1/34 (2.9%) and VL discordance in 6/34 (17.6%). Discordance was not associated with CD4 count, antiretroviral status, fungal burden, CSF lymphocyte percentage nor mental status. Twenty-six of 45 (57.8%) CSF/plasma pairs were successfully sequenced. HIV-1 DRM discordance was found in 3/26 (11.5%); 1 had I84IT and another had M46MI in CSF only. The third had K101E in plasma and V106 M in CSF.Our findings suggest that HIV-1 escape and DRM discordance may occur at lower rates in participants with advanced HIV-disease and CM compared to those with HIV associated neurocognitive impairment.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/sangue , Infecções por HIV/líquido cefalorraquidiano , HIV-1/genética , Meningite Criptocócica/virologia , Adulto , Estudos Transversais , Feminino , Genes pol , Infecções por HIV/virologia , Humanos , Masculino , Meningite Criptocócica/sangue , Meningite Criptocócica/líquido cefalorraquidiano , Mutação , Estudos Retrospectivos , Carga Viral
13.
Stat Med ; 39(24): 3255-3271, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-32875624

RESUMO

Development of methods to accurately estimate human immunodeficiency virus (HIV) incidence rate remains a challenge. Ideally, one would follow a random sample of HIV-negative individuals under a longitudinal study design and identify incident cases as they arise. Such designs can be prohibitively resource intensive and therefore alternative designs may be preferable. We propose such a simple, less resource-intensive study design and develop a weighted log likelihood approach which simultaneously accounts for selection bias and outcome misclassification error. The design is based on a cross-sectional survey which queries individuals' time since last HIV-negative test, validates their test results with formal documentation whenever possible, and tests all persons who do not have documentation of being HIV-positive. To gain efficiency, we update the weighted log likelihood function with potentially misclassified self-reports from individuals who could not produce documentation of a prior HIV-negative test and investigate large sample properties of validated sub-sample only versus pooled sample estimators through extensive Monte Carlo simulations. We illustrate our method by estimating incidence rate for individuals who tested HIV-negative within 1.5 and 5 years prior to Botswana Combination Prevention Project enrolment. This article establishes that accurate estimates of HIV incidence rate can be obtained from individuals' history of testing in a cross-sectional cohort study design by appropriately accounting for selection bias and misclassification error. Moreover, this approach is notably less resource-intensive compared to longitudinal and laboratory-based methods.


Assuntos
Infecções por HIV , Botsuana , Estudos de Coortes , Estudos Transversais , HIV , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Incidência , Funções Verossimilhança , Estudos Longitudinais
14.
Viruses ; 12(7)2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640609

RESUMO

Hepatitis B virus (HBV) is the primary cause of liver-related malignancies worldwide, and there is no effective cure for chronic HBV infection (CHB) currently. Strong immunological responses induced by T cells are associated with HBV clearance during acute infection; however, the repertoire of epitopes (epi) presented by major histocompatibility complexes (MHCs) to elicit these responses in various African populations is not well understood. In silico approaches were used to map and investigate 15-mers HBV peptides restricted to 9 HLA class II alleles with high population coverage in Botswana. Sequences from 44 HBV genotype A and 48 genotype D surface genes (PreS/S) from Botswana were used. Of the 1819 epi bindings predicted, 20.2% were strong binders (SB), and none of the putative epi bind to all the 9 alleles suggesting that multi-epitope, genotype-based, population-based vaccines will be more effective against HBV infections as opposed to previously proposed broad potency epitope-vaccines which were assumed to work for all alleles. In total, there were 297 unique epi predicted from the 3 proteins and amongst, S regions had the highest number of epi (n = 186). Epitope-densities (Depi) between genotypes A and D were similar. A number of mutations that hindered HLA-peptide binding were observed. We also identified antigenic and genotype-specific peptides with characteristics that are well suited for the development of sensitive diagnostic kits. This study identified candidate peptides that can be used for developing multi-epitope vaccines and highly sensitive diagnostic kits against HBV infection in an African population. Our results suggest that viral variability may hinder HBV peptide-MHC binding, required to initiate a cascade of immunological responses against infection.


Assuntos
Antígenos HLA/imunologia , Vírus da Hepatite B/imunologia , Leucócitos/imunologia , Alelos , Botsuana/epidemiologia , Simulação por Computador , Epitopos de Linfócito T/imunologia , Genes MHC da Classe II/imunologia , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Linfócitos T/imunologia
15.
Int J Cancer ; 146(6): 1667-1673, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325316

RESUMO

Cervical cancer remains a significant cause of morbidity and mortality in women worldwide and is the leading cause of cancer-related death in Botswana. It is well established that women with HIV have a higher risk of persistent HPV infection leading to cervical cancer. We assessed HPV prevalence and genotype distribution in 126 tissue specimens from confirmed invasive cervical cancer cases using Abbott real-time PCR assay. Overall, 88 (69.8%) women were HIV-infected. Fifty-seven (64.8%) of the HIV-infected women had a baseline CD4+ count ≥350 cells/µl, and 82 (93.2%) were on antiretroviral therapy at the time of cervical cancer diagnosis. The median age of HIV-infected patients was significantly younger than that of HIV-uninfected patients (p < 0.001). HPV DNA was detected in all of 126 (100%) of tissues analyzed in our study. The HPV genotypes identified included the HPV-16 (75.4%), HPV-18 (28.6%) and other high-risk (hr) HPV genotypes (16.7%). HIV infection was positively associated with the presence of the HPV-16 genotype (p = 0.036), but not with HPV-18 or with other high-risk (hr)-HPV genotypes. Thirty-three percent of the patients had multiple hr-HPV genotypes, with higher rates in HIV-infected women. These results highlight the importance and potential impact of large-scale HPV vaccination programs covering HPV-16 and HPV-18 genotypes in countries like Botswana with high burden of HIV infection.


Assuntos
Infecções por HIV/virologia , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Fármacos Anti-HIV/uso terapêutico , Botsuana/epidemiologia , Colo do Útero/patologia , Colo do Útero/virologia , Efeitos Psicossociais da Doença , Estudos Transversais , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Genótipo , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Prevalência , Estudos Retrospectivos , Neoplasias do Colo do Útero/complicações , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Vacinação
16.
BMC Infect Dis ; 19(1): 875, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640596

RESUMO

BACKGROUND: Hepatitis C virus (HCV) infection is a major cause of chronic liver disease globally. Direct acting antivirals (DAAs) have proven effective in curing HCV. However, the current standard of care (SOC) in Botswana remains PEGylated interferon-α (IFN-α) with ribavirin. Several mutations have been reported to confer resistance to interferon-based treatments. Therefore, there is a need to determine HCV genotypes in Botswana, as these data will guide new treatment guidelines and understanding of HCV epidemiology in Botswana. METHODS: This was a retrospective cross-sectional pilot study utilizing plasma obtained from 55 participants from Princess Marina Hospital in Gaborone, Botswana. The partial core region of HCV was amplified, and genotypes were determined using phylogenetic analysis. RESULTS: Four genotype 5a and two genotype 4v sequences were identified. Two significant mutations - K10Q and R70Q - were observed in genotype 5a sequences and have been associated with increased risk of hepatocellular carcinoma (HCC), while R70Q confers resistance to interferon-based treatments. CONCLUSION: Genotypes 5a and 4v are circulating in Botswana. The presence of mutations in genotype 5 suggests that some patients may not respond to IFN-based regimens. The information obtained in this study, in addition to the World health organization (WHO) recommendations, can be utilized by policy makers to implement DAAs as the new SOC for HCV treatment in Botswana.


Assuntos
Hepacivirus/genética , Hepatite C/virologia , Mutação , Filogenia , Adulto , Antivirais/uso terapêutico , Botsuana , Carcinoma Hepatocelular/virologia , Estudos Transversais , Farmacorresistência Viral , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Hepacivirus/isolamento & purificação , Hepatite C/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Ribavirina/uso terapêutico
17.
N Engl J Med ; 381(3): 230-242, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31314967

RESUMO

BACKGROUND: The feasibility of reducing the population-level incidence of human immunodeficiency virus (HIV) infection by increasing community coverage of antiretroviral therapy (ART) and male circumcision is unknown. METHODS: We conducted a pair-matched, community-randomized trial in 30 rural or periurban communities in Botswana from 2013 to 2018. Participants in 15 villages in the intervention group received HIV testing and counseling, linkage to care, ART (started at a higher CD4 count than in standard care), and increased access to male circumcision services. The standard-care group also consisted of 15 villages. Universal ART became available in both groups in mid-2016. We enrolled a random sample of participants from approximately 20% of households in each community and measured the incidence of HIV infection through testing performed approximately once per year. The prespecified primary analysis was a permutation test of HIV incidence ratios. Pair-stratified Cox models were used to calculate 95% confidence intervals. RESULTS: Of 12,610 enrollees (81% of eligible household members), 29% were HIV-positive. Of the 8974 HIV-negative persons (4487 per group), 95% were retested for HIV infection over a median of 29 months. A total of 57 participants in the intervention group and 90 participants in the standard-care group acquired HIV infection (annualized HIV incidence, 0.59% and 0.92%, respectively). The unadjusted HIV incidence ratio in the intervention group as compared with the standard-care group was 0.69 (P = 0.09) by permutation test (95% confidence interval [CI], 0.46 to 0.90 by pair-stratified Cox model). An end-of-trial survey in six communities (three per group) showed a significantly greater increase in the percentage of HIV-positive participants with an HIV-1 RNA level of 400 copies per milliliter or less in the intervention group (18 percentage points, from 70% to 88%) than in the standard-care group (8 percentage points, from 75% to 83%) (relative risk, 1.12; 95% CI, 1.09 to 1.16). The percentage of men who underwent circumcision increased by 10 percentage points in the intervention group and 2 percentage points in the standard-care group (relative risk, 1.26; 95% CI, 1.17 to 1.35). CONCLUSIONS: Expanded HIV testing, linkage to care, and ART coverage were associated with increased population viral suppression. (Funded by the President's Emergency Plan for AIDS Relief and others; Ya Tsie ClinicalTrials.gov number, NCT01965470.).


Assuntos
Antirretrovirais/uso terapêutico , Circuncisão Masculina , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Programas de Rastreamento , Adolescente , Adulto , Botsuana/epidemiologia , Circuncisão Masculina/estatística & dados numéricos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Incidência , Masculino , Administração Massiva de Medicamentos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , População Rural , Fatores Socioeconômicos , Carga Viral , Adulto Jovem
18.
PLoS One ; 14(1): e0211260, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30699172

RESUMO

BACKGROUND: High-risk human papillomavirus (HR-HPV) has been demonstrated to be the necessary cause of cervical carcinoma. High-risk HPV detection has a prognostic significance for the women who are at increased risk of disease progression. HPV genotyping in cervical cancer precursor lesions is crucial for prevention and management of cervical cancer. This study was designed to investigate the distribution of HR-HPV genotypes among a group of patients with high-grade squamous intraepithelial lesions and higher, of the cervix, in Botswana. MATERIALS AND METHODS: 185-archived residual formalin-fixed paraffin-embedded cervical biopsies collected between the years, 2006 and 2008 were studied. These tissues were diagnosed with HSIL (n = 146) and squamous cell carcinoma (n = 39). DNA was extracted using the Abbott m2000 analyser (Abbott Laboratories, Illinois) using reagents provided by the manufacturer. HPV genotyping was done using the Abbott RealTime HR-HPV PCR, which qualitatively detects 14 HR-HPV (reported as HPV 16, 18 & Other HR-HPV). RESULTS: DNA was successfully extracted from 162/185 (87.6%) tissues as indicated by a positive ß-globin test. 132/162 (82%) tested positive for HR-HPV The HPV 16 prevalence was 50% (66/132), HPV 18 at 15.2% (20/132) and other Group 1 HR-HPV plus HPV 66 and 68 had a prevalence of 56.1% (74/132). Other HR-HPV types were common in HSIL than in carcinoma, while HPV 16 was more prevalent in carcinomas than other HR-HPV genotypes. CONCLUSION: In this study, HPV 16 and other HR-HPV genotypes were commonly associated with HSIL but HPV 18 was uncommon among Botswana women. Our data highlights the need for multivalent HPV vaccines with cross coverage for other high risk HPV other than HPV 16 and 18.


Assuntos
Alphapapillomavirus/classificação , Carcinoma de Células Escamosas/virologia , Técnicas de Genotipagem/métodos , Infecções por Papillomavirus/epidemiologia , Lesões Intraepiteliais Escamosas Cervicais/virologia , Adulto , Alphapapillomavirus/genética , Biópsia , Botsuana , Carcinoma de Células Escamosas/patologia , Progressão da Doença , Feminino , Humanos , Infecções por Papillomavirus/diagnóstico , Inclusão em Parafina , Prevalência , Prognóstico , Lesões Intraepiteliais Escamosas Cervicais/patologia , Fixação de Tecidos
19.
Virus Genes ; 55(1): 33-42, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30382563

RESUMO

Hepatitis B virus (HBV) poses a significant threat to blood transfusion safety in sub-Saharan Africa (SSA) where allogeneic blood donations are screened serologically, and more sensitive nucleic acid tests (NATs) are utilized infrequently. HBV strains circulating among blood donors in Botswana are not yet characterized. We designed a cross-sectional study to determine the HBV sub-genotypes and prevalence of hepatitis B surface antigen (HBsAg) among blood donors between November 2014 and October 2015. A total of 12,575 blood donations were screened for HBsAg and 50 consecutive plasma samples were selected for genotyping from confirmed HBsAg+ donations. Overlapping Pol and complete S (Pol/S) open reading frames (ORFs) were sequenced from extracted HBV DNA. To identify any signature amino acids, mutations were compared to sequences from a cohort of chronic HBV patients co-infected with HIV and were treatment naïve. The prevalence of HBsAg+ blood donors was 1.02% (95% CI 0.9-1.2%), and the circulating sub-genotypes were A1 serotype adw2 (36.1%), D2 serotype ayw2 (2.9%), and D3 serotypes ayw 1/2 (58.3%). Prevalence of escape mutations was 14% from HBV isolates of blood donors and 15% from isolates of HBV/HIV co-infected patients (p = 0.6926). The escape mutations sP120L, sG130R, sY134H, and sD144A were identified predominantly among HBV isolates from blood donors. These escape mutations have been associated with accelerated HBV sequelae [e.g., liver cirrhosis (LC) and hepatocellular carcinoma (HCC)], failure to detect HBsAg, inability to respond to immunoglobulin (Ig) therapy, and HBV vaccine escape. Characterizing the HBV burden, circulating sub-genotypes, and clinically relevant mutations among blood donors in Botswana is important to elucidate the efficacy of currently available vaccines, predicting HBV-transmission patterns, understanding the cohort's risk to HBV-related complications, and to developing prevention strategies and effective genotype-based antiretroviral therapies.


Assuntos
Doadores de Sangue , Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Hepatite B/virologia , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Botsuana/epidemiologia , Estudos Transversais , DNA Viral/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Filogenia , Reação em Cadeia da Polimerase , Vigilância da População , Prevalência , Sorogrupo , Adulto Jovem
20.
Genes (Basel) ; 9(9)2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30134551

RESUMO

Occult hepatitis B infections (OBI) represent a reservoir of undiagnosed and untreated hepatitis B virus (HBV), hence the need to identify mutations that lead to this phenotype. Functionally characterizing these mutations by in vitro studies is time-consuming and expensive. To bridge this gap, in silico approaches, which predict the effect of amino acid (aa) variants on HBV protein function, are necessary. We developed an algorithm for determining the relevance of OBI-associated mutations using in silico approaches. A 3 kb fragment of subgenotypes A1 and D3 from 24 chronic HBV-infected (CHB) and 24 OBI participants was analyzed. To develop and validate the algorithm, the effects of 68 previously characterized occult-associated mutations were determined using three computational tools: PolyPhen2, SNAP2, and PROVEAN. The percentage of deleterious mutations (with impact on protein function) predicted were 52 (76.5%) by PolyPhen2, 55 (80.9%) by SNAP2, and 65 (95.6%) by PROVEAN. At least two tools correctly predicted 59 (86.8%) mutations as deleterious. To identify OBI-associated mutations exclusive to Botswana, study sequences were compared to CHB sequences from GenBank. Of the 43 OBI-associated mutations identified, 26 (60.5%) were predicted by at least two tools to have an impact on protein function. To our knowledge, this is the first study to use in silico approaches to determine the impact of OBI-associated mutations, thereby identifying potential candidates for functional analysis to facilitate mechanistic studies of the OBI phenotype.

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