11 research outputs found
Transmitted Drug Resistance among People Living with HIV/Aids at Major Cities of Sao Paulo State, Brazil
Human immunodeficiency virus type 1 (HIV-1) transmitted drug resistance (TDR) is an important public health issue. In Brazil, low to intermediate resistance levels have been described. We assessed 225 HIV-1 infected, antiretroviral naïve individuals, from HIV Reference Centers at two major metropolitan areas of Sao Paulo (Sao Paulo and Campinas), the state that concentrates most of the Brazilian Aids cases. TDR was analyzed by Stanford Calibrated Population Resistance criteria (CPR), and mutations were observed in 17 individuals (7.6%, 95% CI: 4.5%–11.9%). Seventy-six percent of genomes (13/17) with TDR carried a nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance mutation, mostly K103N/S (9/13, 69%), potentially compromising the preferential first-line therapy suggested by the Brazilian HIV Treatment Guideline that recommends efavirenz-based combinations. Moreover, 6/17 (35%) had multiple mutations associated with resistance to one or more classes. HIV-1 B was the prevalent subtype (80%); other subtypes include HIV-1 F and C, mosaics BC, BF, and single cases of subtype A1 and CRF02_AG. The HIV Reference Center of Campinas presented more cases with TDR, with a significant association of TDR with clade B infection (P<0.05)
Long Terminal Repeat Sequence Analysis of HTLV-2 Molecular Variants Identified in Southern Brazil
In Brazil, human T-lymphotropic virus type 2 (HTLV-2) is endemic in Amerindians and epidemic in intravenous drug users (IDUs). The long terminal repeat (LTR) is the most divergent genomic region of HTLV-2, therefore useful to characterize subtypes. Nucleotide sequence and restriction fragment length polymorphism (RFLP) analysis of LTR genomic segments of fourteen HTLV-2 strains isolated from HIV-infected patients of Londrina, Southern Brazil, were carried out. Molecular analysis disclosed that all HTLV-2 strains belonged to 2a subtype, and RFLP detected the presence of the a4, a5, and a6 subgroups according to Switzer's nomenclature. RFLP correlated with nucleotide sequence, and phylogenetic analysis clustered HTLV-2 sequences of IDUs into subgroups a5 and a6. HTLV-2 sequences from individuals of sexual risk factor clustered into the a4 subgroup. These results extend the knowledge of the genetic diversity of HTLV-2 circulating in Brazil and provide insights into HTLV-2 transmission and virus movement in this geographic area.Ministerio da Ciencia e Tecnologia/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (MCT/CNPq), Brasil[481040/2007-2]Ministerio da Ciencia e Tecnologia/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (MCT/CNPq), Brasil[303328/2009-6
Phylogenetic and Similarity Analysis of HTLV-1 Isolates from HIV-Coinfected Patients from the South and Southeast Regions of Brazil
HTLV-1 is endemic in Brazil and HIV/ HTLV-1 coinfection has been detected, mostly in the northeast region. Cosmopolitan HTLV-1a is the main subtype that circulates in Brazil. This study characterized 17 HTLV-1 isolates from HIV coinfected patients of southern (n = 7) and southeastern (n = 10) Brazil. HTLV-1 provirus DNA was amplified by nested PCR (env and LTR) and sequenced. Env sequences (705 bp) from 15 isolates and LTR sequences (731 bp) from 17 isolates showed 99.5% and 98.8% similarity among sequences, respectively. Comparing these sequences with ATK (HTLV-1a) and Mel5 (HTLV-1c) prototypes, similarities of 99% and 97.4%, respectively, for env and LTR with ATK, and 91.6% and 90.3% with Mel5, were detected. Phylogenetic analysis showed that all sequences belonged to the transcontinental subgroup A of the Cosmopolitan subtype, clustering in two Latin American clusters.Ministerio da Ciencia e Tecnologia/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (MCT/CNPq), Brazil [481040/2007-2, 303328/2009-6]Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), BrazilInstituto Adolfo Lutz [39/07
HIV-1 tropism and CD4 T lymphocyte recovery in a prospective cohort of patients initiating HAART in Ribeirão Preto, Brazil
While human immunodeficiency virus (HIV)-1 chemokine co-receptors 5 tropism and the GWGR motif in the envelope third variable region (V3 loop) have been associated with a slower disease progression, their influence on antiretroviral response remains unclear. The impact of baseline V3 characteristics on treatment response was evaluated in a randomised, double blind, prospective cohort study with patients initiating highly active antiretroviral therapy with lopinavir or efavirenz plus azithothymidine/3TC (1:1) over 48 weeks. Similar virological and immunological responses were observed for both treatment regimens. The 43 individuals had a mean baseline CD4 T cell count of 119 cells/mm³ [standard deviation (SD) = 99] and a mean viral load of 5.09 log10 copies/mL (SD = 0.49). The GWGR motif was not associated with a CD4 T cell response, but predicted R5 tropism by the geno2pheno[clinical20%] algorithm correlated with higher CD4 T cell levels at all monitoring points (p < 0.05). Moreover, higher false-positive rates (FPR) values from this analysis revealed a strong correlation with CD4 T cell recovery (p < 0.0001). Transmitted drug resistance mutations, documented in 3/41 (7.3%) cases, were unrelated to the assigned antiretroviral regimen and had no impact on patient outcomes. In conclusion, naÏve HIV-1 R5 infected patients exhibited higher CD4 T cell counts at baseline; this difference was sustained throughout therapy. The geno2pheno[clinical] option FPR positively correlated with CD4 T cell gain and may be useful in predicting CD4 T cell recovery
Molecular Characterisation of Newly Identified HIV-1 Infections in Curitiba, Brazil: Preponderance of Clade C Among Males With Recent Infections
As in many areas of Brazil, the AIDS epidemic in Curitiba is relatively
stable, but surveillance is important to support public policy. The
molecular characteristics of HIV may be instrumental for monitoring
epidemic trends. We evaluated plasma HIV-1 RNA (n = 37) from 38 cases
presenting with positive serology, who were among 820 consenting
volunteers visiting the downtown counselling and serology testing
centre. Seroprevalence was 4.6% (CI 95% 3.2-6.3) and the estimated HIV
incidence, as defined by the BED assay, was 2.86 persons/years (CI 95%
1.04-4.68). An additional set of contemporaneous, anonymous samples
from a local laboratory was also analysed (n = 20). Regions of the
HIV-1 polymerase (n = 57) and envelope (n = 34) were evaluated for
subtyping, determination of mosaic structure, primary drug resistance
mutations (pDRM), envelope V3 loop motifs and amino acid signatures
related to viral tropism. HIV-1 clade B was observed in 53% of cases;
HIV-1C in 30% and BC mosaics in 14%, with one F genome and one CF
mosaic. Clade C infection was associated with recent infections among
males (p < 0.03). Stanford surveillance pDRM was observed in 8.8% of
sequences, with 7% showing high level resistance to at least one
antiretroviral drug. Tropism for CXCR4 co-receptor was predicted in 18%
of envelope sequences, which were exclusively among clade B genomes and
cases with serological reactivity to chronic infection
Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine (CoronaVac) in inadvertently vaccinated healthy children
Twenty-seven children aged seven months to 5 years were inadvertently vaccinated with a COVID-19 vaccine, the CoronaVac (Sinovac, China), an inactivated SARS-CoV-2 vaccine, in two different cities of Sao Paulo State, Brazil. After the event, these children were monitored by local pediatricians and serum samples were collected at the first visit and 30 days after vaccination and tested for SARS-CoV-2 S1 serology with Ortho total IgG anti-S1 protein and Cpass, an ACE2 receptor binding domain inhibition assay. Only one child had a mild symptom after vaccination, with no other adverse events documented up to the 30 days follow-up. Of 27 children tested 3-9 days after vaccination, 5 (19%) had positive serology suggesting a previous natural SARS-CoV-2 infection, with all 19 tested on day 30 after vaccination and presenting with positive tests, with an increment of antibody titers in those initially positive. A low Cpass binding inhibition was observed in the first collection in 11 seronegative cases, with high titers among those anti-S1 positive. All children showed an important increase in antibody titers on day 30. The event allowed the documentation of a robust serological response to one dose of CoronaVac in this small population of young children, with no major adverse effects. Although it was an unfortunate accident, this event may contribute with future vaccine strategies in this age group. The data suggest that CoronaVac is safe and immunogenic for children