Seble Kassaye
Georgetown University
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Featured researches published by Seble Kassaye.
PLOS ONE | 2010
Vici Varghese; Elijah Wang; Farbod Babrzadeh; Michael H. Bachmann; Rajin Shahriar; Tommy F. Liu; Svetlana Jean M. Mappala; Baback Gharizadeh; W. Jeffrey Fessel; David Katzenstein; Seble Kassaye; Robert W. Shafer
Background The HIV-1 nucleoside RT inhibitor (NRTI)-resistance mutation, K65R confers intermediate to high-level resistance to the NRTIs abacavir, didanosine, emtricitabine, lamivudine, and tenofovir; and low-level resistance to stavudine. Several lines of evidence suggest that K65R is more common in HIV-1 subtype C than subtype B viruses. Methods and Findings We performed ultra-deep pyrosequencing (UDPS) and clonal dideoxynucleotide sequencing of plasma virus samples to assess the prevalence of minority K65R variants in subtype B and C viruses from untreated individuals. Although UDPS of plasma samples from 18 subtype C and 27 subtype B viruses showed that a higher proportion of subtype C viruses contain K65R (1.04% vs. 0.25%; p<0.001), limiting dilution clonal sequencing failed to corroborate its presence in two of the samples in which K65R was present in >1.5% of UDPS reads. We therefore performed UDPS on clones and site-directed mutants containing subtype B- and C-specific patterns of silent mutations in the conserved KKK motif encompassing RT codons 64 to 66 and found that subtype-specific nucleotide differences were responsible for increased PCR-induced K65R mutation in subtype C viruses. Conclusions This study shows that the RT KKK nucleotide template in subtype C viruses can lead to the spurious detection of K65R by highly sensitive PCR-dependent sequencing techniques. However, the study is also consistent with the subtype C nucleotide template being inherently responsible for increased polymerization-induced K65R mutations in vivo.
BMC Public Health | 2013
Larissa Jennings; John Ong’ech; Rogers Simiyu; Martin Sirengo; Seble Kassaye
BackgroundCommunity-based mobile phone programs can complement gaps in clinical services for prevention of mother-to-child transmission (PMTCT) of HIV in areas with poor infrastructure and personnel shortages. However, community and health worker perceptions on optimal mobile phone communication for PMTCT are underexplored. This study examined what specific content and forms of mobile communication are acceptable to support PMTCT.MethodsQualitative methods using focus groups and in-depth interviews were conducted in two district hospitals in Nyanza Province, Kenya. A total of 45 participants were purposefully selected, including HIV-positive women enrolled in PMTCT, their male partners, community health workers, and nurses. Semi-structured discussion guides were used to elicit participants’ current mobile phone uses for PMTCT and their perceived benefits and challenges. We also examined participants’ views on platform design and gender-tailored short message service (SMS) messages designed to improve PMTCT communication and male involvement.ResultsMost participants had access to a mobile phone and prior experience receiving and sending SMS, although phone sharing was common among couples. Mobile phones were used for several health-related purposes, primarily as voice calls rather than texts. The perceived benefits of mobile phones for PMTCT included linking with health workers, protecting confidentiality, and receiving information and reminders. Men and women considered the gender-tailored SMS as a catalyst for improving PMTCT male involvement and couples’ communication. However, informative messaging relayed safely to the intended recipient was critical. In addition, health workers emphasized the continual need for in-person counseling coupled with, rather than replaced by, mobile phone reinforcement. For all participants, integrated and neutral text messaging provided antenatally and postnatally was most preferred, although not all topics or text formats were equally acceptable.ConclusionsGiven the ubiquity of mobile phones in Kenya and current health-related uses of mobile phones, a PMTCT mobile communications platform holds considerable potential. This pre-intervention assessment of community and health worker preferences yielded valuable information on the complexities of design and implementation. An effective PMTCT mobile platform engaging men and women will need to address contexts of non-disclosure, phone sharing, and linkages with existing community and facility-based services.
Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2009
Rena Patel; Seble Kassaye; Cheryl Gore-Felton; Grace Wyshak; Gerard Kadzirange; Godfrey Woelk; David Katzenstein
Abstract Little is known about the psychosocial impact of antiretroviral therapy (ART) among women in sub-Saharan Africa. Therefore, we conducted a cross-sectional study in Zimbabwe to assess the impact of ART on HIV-positive womens health-related quality of life, using the Medical Outcomes Study-HIV Quality of Life (QOL) questionnaire. Additionally, we assessed socio-demographics, reproductive and sexual health, HIV-related history, disclosure, social stigma, self-esteem, and depression. Structured interviews were conducted with 200 HIV-positive women and categorized into three groups by treatment: (1) Group 1 (n=31) did not meet clinical or laboratory criteria to begin treatment; (2) Group 2 (n=73) was eligible to begin treatment but awaiting initiation of treatment; and (3) Group 3 (n=96) was on ART for a median of 13 months. The women had similar socio-demographic characteristics but varied significantly in clinical characteristics. Women on ART reported fewer AIDS-related symptoms in the last week and year and had higher current and lower baseline CD4 counts compared to women not on ART. On most QOL domains women on ART reported higher mean scores as compared to women not on ART (p<0.01). Additionally, women on ART reported less depression compared to women not on ART (p<0.001). Between the two groups of women not on ART, unexpectedly, there were no significant differences in their scores for QOL or depression. Thus, Zimbabwean women living with HIV experience better overall QOL and lower depression on ART. Altogether, our findings suggest that ART delivery in resource-poor communities can enhance overall QOL as well as psychosocial functioning, which has wide-ranging public health implications.
AIDS | 2009
Sudeb C. Dalai; Tulio de Oliveira; Gordon William Harkins; Seble Kassaye; Jennifer Lint; Justen Manasa; Elizabeth Johnston; David Katzenstein
Objective:To investigate the origins and evolutionary history of subtype C HIV-1 in Zimbabwe in a context of regional conflict and migration. Design:HIV-1C pol sequence datasets were generated from four sequential cohorts of antenatal women in Harare, Zimbabwe sampled over 15 years (1991–2006). Methods:One hundred and seventy-seven HIV-1C pol sequences were obtained from four successive cohorts in Zimbabwe. Maximum-likelihood methods were used to explore phylogenetic relationships between Zimbabwean HIV-1C sequences and subtype C strains from other regions. A Bayesian coalescent-based framework was used to estimate evolutionary parameters for HIV-1C in Zimbabwe, including origin and demographic growth patterns. Results:Zimbabwe HIV-1C pol demonstrated increasing sequence divergence over the 15-year period. Nearly all Zimbabwe sequences clustered phylogenetically with subtype C strains from neighboring countries. Bayesian evolutionary analysis indicated a most recent common ancestor date of 1973 with three epidemic growth phases: an initial, slow phase (1970s) followed by exponential growth (1980s), and a linearly expanding epidemic to the present. Bayesian trees provided evidence for multiple HIV-1C introductions into Zimbabwe during 1979–1981, corresponding with Zimbabwean national independence following a period of socio-political instability. Conclusion:The Zimbabwean HIV-1C epidemic likely originated from multiple introductions in the late 1970s and grew exponentially during the 1980s, corresponding to changing political boundaries and rapid population influx from neighboring countries. The timing and phylogenetic clustering of the Zimbabwean sequences is consistent with an origin in southern Africa and subsequent expansion. HIV-1 sequence data contain important epidemiological information, which can help focus treatment and prevention strategies in light of more recent political volatility in Zimbabwe.
Clinical Infectious Diseases | 2016
Seble Kassaye; Zehava Grossman; Maya Balamane; Betsy Johnston-White; Chenglong Liu; Princy Kumar; Mary Young; Michael C. Sneller; Irini Sereti; Robin L. Dewar; Catherine Rehm; William A. Meyer; Robert W. Shafer; David Katzenstein; Frank Maldarelli
BACKGROUND Washington, DC, has 2.5% human immunodeficiency virus (HIV) prevalence, 3.9% among African Americans. Antiretrovirals (ARTs) are the cornerstone for treatment and prevention. Monitoring changes in transmitted drug resistance (TDR) is critical for effective HIV care. METHODS HIV genotype data for individuals enrolled in research studies in metropolitan Washington, D.C., were used to identify TDR using the World Health Organization mutation list [Bennett DE, Camacho RJ, Otelea D, et al. Drug resistance mutations for surveillance of transmitted HIV-1 drug-resistance: 2009 update. PloS One 2009; 4:e4724]. HIV phylogenies were reconstructed using maximum likelihood and Bayesian methods. HIV transmission clusters were supported by 1000 bootstrap values >0.70 and posterior probability >0.95 of having a common ancestor. RESULTS Among 710 individuals enrolled in 1994-2013, the median age was 38.6 years, 46.2% were female, and 53.3% were African-American. TDR was 22.5% among 566 treatment-naive individuals; 15.8% had nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) resistance, 9.8% had nonnucleoside reverse-transcriptase inhibitor (NNRTI) resistance, and 4.2% had protease inhibitor (PI) resistance. Single class TDR was 10.0%, 5.1%, and 1.6% to NRTIs, NNRTIs, and PIs. Dual TDR to PI and NRTI was seen in 1.6%, NRTI and NNRTI in 3.4%, and triple class TDR in 0.9%. TDR frequency decreased from 1994-2006 (27.1%) to 2007-2013 (19.4%; P = .02). Only 6/79 (7.6%) individuals within transmission clusters had evidence of TDR. DISCUSSIONS We identified high prevalence of TDR among HIV-infected individuals in metropolitan Washington, DC, regardless of gender. Active surveillance for TDR is needed to guide ART usage and analyses of risk group contributions to HIV transmission and resistance.
PLOS ONE | 2011
Mqondisi Tshabalala; Justen Manasa; Lynn S. Zijenah; Simbarashe Rusakaniko; Gerard Kadzirange; Mary Mucheche; Seble Kassaye; Elizabeth Johnston; David Katzenstein
The rapid scale-up of highly active antiretroviral therapy (HAART) and use of single dose Nevirapine (SD NVP) for prevention of mother-to-child transmission (pMTCT) have raised fears about the emergence of resistance to the first line antiretroviral drug regimens. A cross-sectional study was conducted to determine the prevalence of primary drug resistance (PDR) in a cohort of young (<25 yrs) HAART-naïve HIV pregnant women attending antenatal clinics in Chitungwiza, Zimbabwe. Whole blood was collected in EDTA for CD4 counts, viral load, serological estimation of duration of infection using the BED Calypte assay and genotyping for drug resistance. Four hundred and seventy-one women, mean age 21 years; SD: 2.1 were enrolled into the study between 2006 and 2007. Their median CD4 count was 371cells/µL; IQR: 255–511 cells/µL. Two hundred and thirty-six samples were genotyped for drug resistance. Based on the BED assay, 27% were recently infected (RI) whilst 73% had long-term infection (LTI). Median CD4 count was higher (p<0.05) in RI than in women with LTI. Only 2 women had drug resistance mutations; protease I85V and reverse transcriptase Y181C. Prevalence of PDR in Chitungwiza, 4 years after commencement of the national ART program remained below WHO threshold limit (5%). Frequency of recent infection BED testing is consistent with high HIV acquisition during pregnancy. With the scale-up of long-term ART programs, maintenance of proper prescribing practices, continuous monitoring of patients and reinforcement of adherence may prevent the acquisition and transmission of PDR.
Journal of Acquired Immune Deficiency Syndromes | 2009
Seble Kassaye; Elizabeth Johnston; Bryan McColgan; Rami Kantor; Lynn S. Zijenah; David Katzenstein
Background:In resource-constrained settings, antiretroviral treatment (ART) is often continued based on clinical and CD4 responses, without virologic monitoring. ART with incomplete viral suppression was assessed in 27 subjects with subtype C HIV-1. Methods:Plasma HIV-1 RNA, drug resistance, viral tropism, and evolution in polymerase (pol) and envelope (env) genes were measured. The association between these viral parameters and CD4 cell change over time was analyzed using linear regression models. Results:Increased area under the curve of HIV-1 RNA replication was a predictor of lower CD4 cell gains (P < 0.007), while less drug resistance measured as a genotypic susceptibility score (GSS) (P = 0.065), and lower rates of evolution in pol and env genes (P = 0.08 and 0.097, respectively) measured as genetic distance were modestly associated with increasing CD4 cell counts. Evolution of pol and env were correlated (R2 = 0.48, P = 0.005), however, greater evolution was identified in env vs. pol (P < 0.05). CXCR4-usage (X4) was detected in 14/27 (52%) but no differences in CD4 cell change or plasma viremia were associated with X4-usage. Discussion:Among subtype C HIV-1 infected patients in Zimbabwe receiving incompletely suppressive ART, higher virus replication and lower CD4 cell gains were associated with drug resistance and evolution of polymerase and envelope.
Journal of Biological Chemistry | 2017
Robert A. Barclay; Angela Schwab; Catherine DeMarino; Yao Akpamagbo; Benjamin Lepene; Seble Kassaye; Sergey Iordanskiy; Fatah Kashanchi
HIV-1 infection causes AIDS, infecting millions worldwide. The virus can persist in a state of chronic infection due to its ability to become latent. We have previously shown a link between HIV-1 infection and exosome production. Specifically, we have reported that exosomes transport viral proteins and RNA from infected cells to neighboring uninfected cells. These viral products could then elicit an innate immune response, leading to activation of the Toll-like receptor and NF-κB pathways. In this study, we asked whether exosomes from uninfected cells could activate latent HIV-1 in infected cells. We observed that irrespective of combination antiretroviral therapy, both short- and long-length viral transcripts were increased in wild-type HIV-1–infected cells exposed to purified exosomes from uninfected cells. A search for a possible mechanism for this finding revealed that the exosomes increase RNA polymerase II loading onto the HIV-1 promoter in the infected cells. These viral transcripts, which include trans-activation response (TAR) RNA and a novel RNA that we termed TAR-gag, can then be packaged into exosomes and potentially be exported to neighboring uninfected cells, leading to increased cellular activation. To better decipher the exosome release pathways involved, we used siRNA to suppress expression of ESCRT (endosomal sorting complex required for transport) proteins and found that ESCRT II and IV significantly control exosome release. Collectively, these results imply that exosomes from uninfected cells activate latent HIV-1 in infected cells and that true transcriptional latency may not be possible in vivo, especially in the presence of combination antiretroviral therapy.
Aids Research and Treatment | 2016
Seble Kassaye; John Ong’ech; Martin Sirengo; Judith Kose; Lucy Matu; Peter McOdida; Rogers Simiyu; Titus Syengo; David Muthama; Rhoderick Machekano
Background. Antiretroviral medications are key for prevention of mother-to-child transmission (PMTCT) of HIV, and transmission mitigation is affected by service delivery, adherence, and retention. Methods. We conducted a cluster-randomized controlled study in 26 facilities in Nyanza, Kenya, to determine the efficacy of SMS text messages on PMTCT outcomes. The relative risk and confidence intervals were estimated at the facility level using STATA. Results. 550 women were enrolled, from June 2012 to July 2013. The median age was 25.6 years, and 85.3% received ARVs. Maternal ARV use was similar between the intervention and control arms: 254/261 (97.3%) versus 241/242 (99.6%) at 34–36 weeks of gestation and 234/247 (94.7%) versus 229/229 (100%) at delivery. Among infants, 199/246 (80.9%) and 209/232 (90.1%) received ARVs (RR: 0.91; 95% CI: 0.77–1.14); 88% versus 88.6% were tested for HIV at 6 weeks, with 1/243 (0.4%) and 3/217 (1.4%) positive results in the intervention and control arms, respectively. Communication increased in both the intervention and control arms, with the mean number of 7.5 (SD: 5.70) compared with 6 (SD: 9.96), p < 0.0001. Conclusions. We identified high ARV uptake and infant HIV testing, with very low HIV transmission. Increased communication may influence health-seeking behaviors irrespective of technology. The long-term effectiveness of facilitated communication on PMTCT outcomes needs to be tested. The study has been registered on ClinicalTrials.gov under the identifier NCT01645865.
Journal of Acquired Immune Deficiency Syndromes | 2016
Christina Ludema; Stephen R. Cole; Joseph J. Eron; Andrew Edmonds; G. Mark Holmes; Kathryn Anastos; Jennifer Cocohoba; Mardge H. Cohen; Hannah L.F. Cooper; Elizabeth T. Golub; Seble Kassaye; Deborah Konkle-Parker; Lisa R. Metsch; Joel Milam; Tracey E. Wilson; Adaora A. Adimora
Background:Implementation of the Affordable Care Act motivates assessment of health insurance and supplementary programs, such as the AIDS Drug Assistance Program (ADAP) on health outcomes of HIV-infected people in the United States. We assessed the effects of health insurance, ADAP, and income on HIV viral load suppression. Methods:We used existing cohort data from the HIV-infected participants of the Womens Interagency HIV Study. Cox proportional hazards models were used to estimate the time from 2006 to unsuppressed HIV viral load (>200 copies/mL) among those with Medicaid, private, Medicare, or other public insurance, and no insurance, stratified by the use of ADAP. Results:In 2006, 65% of women had Medicaid, 18% had private insurance, 3% had Medicare or other public insurance, and 14% reported no health insurance. ADAP coverage was reported by 284 women (20%); 56% of uninsured participants reported ADAP coverage. After accounting for study site, age, race, lowest observed CD4, and previous health insurance, the hazard ratio (HR) for unsuppressed viral load among those privately insured without ADAP, compared with those on Medicaid without ADAP (referent group), was 0.61 (95% CI: 0.48 to 0.77). Among the uninsured, those with ADAP had a lower relative hazard of unsuppressed viral load compared with the referent group (HR, 95% CI: 0.49, 0.28 to 0.85) than those without ADAP (HR, 95% CI: 1.00, 0.63 to 1.57). Conclusions:Although women with private insurance are most likely to be virally suppressed, ADAP also contributes to viral load suppression. Continued support of this program may be especially critical for states that have not expanded Medicaid.