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1.
J Antimicrob Chemother ; 78(6): 1444-1453, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37039023

ABSTRACT

BACKGROUND: Antiretroviral therapy has revolutionized HIV treatment, increasing quality and life expectancy of people living with HIV (PLWH). However, the expansion of treatment has resulted in an increase in antiretroviral-resistant viruses, which can be an obstacle to maintenance of successful ART. OBJECTIVES: This study analysed the genetic composition of the HIV near full-length genome (NFLG) from archived proviruses of PLWH under successful ART, and determined the presence/frequency of drug resistance mutations (DRMs) and viral subtype. PATIENTS AND METHODS: Forty-six PLWH from Rio de Janeiro (RJ) and 40 from Rio Grande (RS) had proviral HIV NFLG PCR-amplified and ultradeep sequenced. The presence/frequency of DRMs were analysed in Geneious. Phylogenetic analyses were performed using PhyML and SimPlot. RESULTS: All samples included in the study were sequenced and 69 (80.2%) had the HIV NFLG determined. RJ and RS showed a predominance of HIV subtypes B (78.3%) and C (67.5%), respectively. Overall, 168 DRMs were found in 63 (73.3%) samples, and 105 (62.5%) of them were minority variants. Among DRMs, 41 (39.0%) minority variants and 33 (52.4%) variants with frequency above 20.0% in the viral population were able to confer some degree of resistance to at least one drug in use by respective patients, yet no one showed signs of therapeutic failure. CONCLUSIONS: Our study contributes to the understanding of the impact of DRMs on successful therapy and supports the sustainability of combinatorial ART, because all patients maintained their successful treatment despite the high prevalence of DRMs at low (62.5%) or high (37.5%) frequency.


Subject(s)
Anti-HIV Agents , HIV Infections , HIV Seropositivity , HIV-1 , Humans , HIV-1/genetics , Phylogeny , Brazil/epidemiology , Anti-Retroviral Agents/pharmacology , Anti-Retroviral Agents/therapeutic use , HIV Seropositivity/drug therapy , Mutation , Proviruses/genetics , Drug Resistance, Viral/genetics , Genotype , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use
2.
Front Microbiol ; 13: 946549, 2022.
Article in English | MEDLINE | ID: mdl-35958144

ABSTRACT

Chronically immunosuppressed patients infected with SARS-CoV-2 often experience prolonged virus shedding, and may pave the way to the emergence of mutations that render viral variants of concern (VOC) able to escape immune responses induced by natural infection or by vaccination. We report herein a SARS-CoV-2+ cancer patient from the beginning of the COVID-19 pandemic whose virus quasispecies across multiple timepoints carried several immune escape mutations found in more contemporary VOC, such as alpha, delta and omicron, that appeared to be selected for during infection. We hypothesize that immunosuppressed patients may represent the source of VOC seen throughout the COVID-19 pandemics.

3.
Infect Genet Evol ; 94: 104998, 2021 10.
Article in English | MEDLINE | ID: mdl-34252616

ABSTRACT

After a one-year rollout of the pandemic caused by SARS-CoV-2, the continuous dissemination of the virus has generated a number of variants with increased transmissibility and infectivity, called variants of concern (VOC), which now predominate worldwide. Concerns about the susceptibility of humans that have already been infected before or those already vaccinated to infection by VOC rise among scientists and clinicians. Herein, we assessed the prevalence of different VOC among recent infections at the Brazilian National Cancer Institute (Rio de Janeiro, Brazil). By using a Sanger-based sequencing approach targeting the viral S gene to identify VOC, we have analyzed 72 recent infections. The overall prevalence of VOC was 97%. Among the subjects analyzed, six had been vaccinated with the ChAdOx1-S/nCoV-19 (n = 4; one with two doses and three with one dose) or the CoronaVac (n = 2; both with 2 doses) vaccine, while five subjects represented reinfection cases, being two of them also part of the vaccinated group (each one with one vaccine type). All vaccinated and re-infected subjects carried VOC irrespective of the vaccine type taken, the number of doses taken, IgG titers or being previously infected during the first wave of the Brazilian pandemic. Importantly, all six vaccinees only had mild symptoms. We present here several examples of how natural infections or vaccination may not be fully capable of conferring sterilizing immunity against VOC.


Subject(s)
COVID-19 Vaccines/administration & dosage , COVID-19/immunology , COVID-19/virology , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/genetics , Brazil/epidemiology , COVID-19/diagnosis , COVID-19/epidemiology , Humans , Pandemics , Phylogeny , SARS-CoV-2/classification , SARS-CoV-2/genetics , Vaccination
4.
PLoS One ; 15(10): e0241261, 2020.
Article in English | MEDLINE | ID: mdl-33104715

ABSTRACT

OBJECTIVE: This study aimed to describe the demographic and clinical characteristics of cancer inpatients with COVID-19 exploring clinical outcomes. METHODS: A retrospective search in the electronic medical records of cancer inpatients admitted to the Brazilian National Cancer Institute from April 30, 2020 to May 26, 2020 granted identification of 181 patients with COVID-19 confirmed by RT-PCR. RESULTS: The mean age was 55.3 years (SD ± 21.1). Comorbidities were present in 110 (60.8%) cases. The most prevalent solid tumors were breast (40 [22.1%]), gastrointestinal (24 [13.3%]), and gynecological (22 [12.2%]). Among hematological malignancies, lymphoma (20 [11%]) and leukemia (10 [5.5%]) predominated. Metastatic disease accounted for 90 (49.7%) cases. In total, 63 (34.8%) had recently received cytotoxic chemotherapy. The most common complications were respiratory failure (70 [38.7%]), septic shock (40 [22.1%]) and acute kidney injury (33 [18.2%]). A total of 60 (33.1%) patients died due to COVID-19 complications. For solid tumors, the COVID-19-specific mortality rate was 37.7% (52 out of 138 patients) and for hematological malignancies, 23.5% (8 out of 34). According to the univariate analysis COVID-19-specific mortality was significantly associated with age over 75 years (P = .002), metastatic cancer (p <0.001), two or more sites of metastases (P < .001), the presence of lung (P < .001) or bone metastases (P = .001), non-curative treatment or best supportive care intent (P < .001), higher C-reactive protein levels (P = .002), admission due to COVID-19 (P = .009), and antibiotics use (P = .02). After multivariate analysis, cases with admission due to symptoms of COVID-19 (P = .027) and with two or more metastatic sites (P < .001) showed a higher risk of COVID-19-specific death. CONCLUSION: This is the first Brazilian cohort of cancer patients with COVID-19. The rates of complications and COVID-19-specific death were significantly high.


Subject(s)
Betacoronavirus , Coronavirus Infections/epidemiology , Inpatients/statistics & numerical data , Neoplasms/epidemiology , Pandemics , Pneumonia, Viral/epidemiology , Academies and Institutes/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Brazil/epidemiology , COVID-19 , Cancer Care Facilities/statistics & numerical data , Cause of Death , Child , Child, Preschool , Comorbidity , Diabetes Mellitus/epidemiology , Disease Susceptibility , Female , Hospital Mortality , Humans , Hypertension/epidemiology , Immunocompromised Host , Infant , Male , Middle Aged , Neoplasms/drug therapy , Retrospective Studies , SARS-CoV-2 , Young Adult
5.
Viruses ; 9(12)2017 12 19.
Article in English | MEDLINE | ID: mdl-29257103

ABSTRACT

Increased access to highly active antiretroviral therapy (HAART) by human immunodeficiency virus postive (HIV⁺) individuals has become a reality worldwide. In Brazil, HAART currently reaches over half of HIV-infected subjects. In the context of a remarkable HIV-1 genetic variability, highly related variants, called quasispecies, are generated. HIV quasispecies generated during infection can influence virus persistence and pathogenicity, representing a challenge to treatment. However, the clinical relevance of minority quasispecies is still uncertain. In this study, we have determined the archived proviral sequences, viral subtype and drug resistance mutations from a cohort of HIV⁺ patients with undetectable viral load undergoing HAART as first-line therapy using next-generation sequencing for near full-length virus genome (NFLG) assembly. HIV-1 consensus sequences representing NFLG were obtained for eleven patients, while for another twelve varying genome coverage rates were obtained. Phylogenetic analysis showed the predominance of subtype B (83%; 19/23). Considering the minority variants, 18 patients carried archived virus harboring at least one mutation conferring antiretroviral resistance; for six patients, the mutations correlated with the current ARVs used. These data highlight the importance of monitoring HIV minority drug resistant variants and their clinical impact, to guide future regimen switches and improve HIV treatment success.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Antiretroviral Therapy, Highly Active , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/classification , Proviruses/classification , Quasispecies , Brazil , Genome, Viral , HIV-1/genetics , HIV-1/isolation & purification , Humans , Proviruses/genetics , Proviruses/isolation & purification , Sequence Analysis, DNA , Viral Load , Whole Genome Sequencing
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