Percorrer por autor "Abecasis, Ana"
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- Accidental father-to-son HIV-1 transmission during the seroconversion periodPublication . Ezeonwumelu, Ifeanyi; Bártolo, Inês; Martin, Francisco; Abecasis, Ana; Campos, Teresa; Romero-Severson, Ethan O.; Leitner, Thomas; Taveira, NunoA 4-year-old child born to an HIV-1 seronegative mother was diagnosed with HIV-1, the main risk factor being transmission from the child's father who was seroconverting at the time of the child's birth. In the context of a forensic investigation, we aimed to identify the source of infection of the child and date of the transmission event. Samples were collected from the father and child at two time points about 4 years after the child's birth. Partial segments of three HIV-1 genes (gag, pol, and env) were sequenced and maximum likelihood (ML) and Bayesian methods were used to determine direction and estimate date of transmission. Neutralizing antibodies were determined using a single cycle assay. Bayesian trees displayed a paraphyletic–monophyletic topology in all three genomic regions, with the father's host label at the root, which is consistent with father-to-son transmission. ML trees found similar topologies in gag and pol and a monophyletic–monophyletic topology in env. Analysis of the time of the most recent common ancestor of each HIV-1 gene population indicated that the child was infected shortly after the father. Consistent with the infection history, both father and son developed broad and potent HIV-specific neutralizing antibody responses. In conclusion, the direction of transmission implicated the father as the source of transmission. Transmission occurred during the seroconversion period when the father was unaware of the infection and was likely accidental. This case shows how genetic, phylogenetic, and serological data can contribute for the forensic investigation of HIV transmission.
- Cruising Venues as a Context for HIV Risky Behavior Among Men Who Have Sex With MenPublication . Gama, Ana; Abecasis, Ana; Pingarilho, Marta; Mendão, Luís; Martins, Maria O.; Barros, Henrique; Dias, SóniaWe examined differences in sexual risk behaviors, HIV prevalence, and demographic characteristics between men who have sex with men (MSM) who visit different types of venues to meet sexual partners, and identified correlates of high-risk behaviors. A cross-sectional behavioral survey was conducted with a venue-based sample of 1011 MSM in Portugal. Overall, 36.3 % of MSM usually visit cruising venues to meet sexual partners (63.7 % only visit social gay venues). Cruising venues' visitors reported higher HIV prevalence (14.6 % [95 % CI 11-18 %] vs. 5.5 % [95 % CI 4-7 %]). Visiting cruising venues was more likely among those older, reporting high number of male sexual partners, group sex, and unprotected anal sex with a partner whose HIV status was unknown. Cruising venues play an important role in increasing risk of HIV transmission among MSM who frequent them. Venue-focused behavioral interventions that promote healthy sexual behaviors are needed.
- Discordant predictions of residual activity could impact dolutegravir prescription upon raltegravir failurePublication . Theys, Kristof; Abecasis, Ana; Libina, Pieter; Gomes, Perpétua; Cabanas, Joaquim; Camacho, Ricardo J.; Van Laethem, KristelBACKGROUND: Dolutegravir is approved for the treatment of HIV-1 patients exposed to other integrase inhibitors, but the decision to use dolutegravir in this setting should be informed by drug resistance testing. OBJECTIVES: This study determined the extent of disagreement in predicted residual dolutegravir activity after raltegravir use, and identified individual mutational patterns for which uncertainty exists among HIV-1 expert systems. STUDY DESIGN: Mutation patterns were classified in raltegravir signature pathways including positions 143, 148 and 155, and interpreted into clinically informative resistance levels using genotypic drug resistance interpretation systems ANRS v24, HIVdb v7.0 and Rega v9.1.0, and instructions of dolutegravir use as approved by the Food and Drug Administration and the European Medicines Agency. RESULTS: In 216HIV-1 patients failing raltegravir-therapy, 87% patients displayed mutations associated with resistance towards integrase inhibitors. A total of 141 unique mutational patterns were observed, with N155H (25.4%), Q148H (16.2%) and Y143R (8.3%) the most prevalent signature mutations. The Q148 pathway occurred almost exclusively in HIV-1 subtype B viruses. Concordances in predicted dolutegravir susceptibility scores among 5 systems were obtained in 57.8% of patients, and concordant intermediate resistant and concordant resistant scores were only observed in 6.5% and 0.9% of patients, respectively. However, systems individually scored higher levels of dolutegravir intermediate resistance and resistance, ranging from 4.2% to 10.2% and from 14.8% to 22.7% of patients, respectively. A consensus on interpreting the extent of residual activity was lacking in 34.7% of patients and was highly resistance pathway-specific. CONCLUSIONS: Dolutegravir may potentially be effective in the majority of HIV-1 patients failing raltegravir, but concern over the uncertainty in predicted residual activity could withhold clinicians from prescribing dolutegravir during its clinical assessment.
- Donor-Recipient identification in para- and poly-phyletic trees under alternative HIV-1 transmission hypotheses using approximate Bayesian computationPublication . Romero-Severson, Ethan O.; Bulla, Ingo; Hengartner, Nick; Bártolo, Inês; Abecasis, Ana; Azevedo-Pereira, José M.; Taveira, Nuno; Leitner, ThomasDiversity of the founding population of Human Immunodeficiency Virus Type 1 (HIV-1) transmissions raises many important biological, clinical, and epidemiological issues. In up to 40% of sexual infections, there is clear evidence for multiple founding variants, which can influence the efficacy of putative prevention methods, and the reconstruction of epidemiologic histories. To infer who-infected-whom, and to compute the probability of alternative transmission scenarios while explicitly taking phylogenetic uncertainty into account, we created an approximate Bayesian computation (ABC) method based on a set of statistics measuring phylogenetic topology, branch lengths, and genetic diversity. We applied our method to a suspected heterosexual transmission case involving three individuals, showing a complex monophyletic-paraphyletic-polyphyletic phylogenetic topology. We detected that seven phylogenetic lineages had been transmitted between two of the individuals based on the available samples, implying that many more unsampled lineages had also been transmitted. Testing whether the lineages had been transmitted at one time or over some length of time suggested that an ongoing superinfection process over several years was most likely. While one individual was found unlinked to the other two, surprisingly, when evaluating two competing epidemiological priors, the donor of the two that did infect each other was not identified by the host root-label, and was also not the primary suspect in that transmission. This highlights that it is important to take epidemiological information into account when analyzing support for one transmission hypothesis over another, as results may be nonintuitive and sensitive to details about sampling dates relative to possible infection dates. Our study provides a formal inference framework to include information on infection and sampling times, and to investigate ancestral node-label states, transmission direction, transmitted genetic diversity, and frequency of transmission.
- HIV-1-Transmitted Drug Resistance and Transmission Clusters in Newly Diagnosed Patients in Portugal Between 2014 and 2019Publication . Pingarilho, Marta; Pimentel, Victor; Miranda, Mafalda N. S.; Silva, Ana Rita; Diniz, António; Ascenção, Bianca Branco; Piñeiro, Carmela; Koch, Carmo; Rodrigues, Catarina; Caldas, Cátia; Morais, Célia; Faria, Domitília; da Silva, Elisabete Gomes; Teófilo, Eugénio; Monteiro, Fátima; Roxo, Fausto; Maltez, Fernando; Rodrigues, Fernando; Gaião, Guilhermina; Ramos, Helena; Costa, Inês; Germano, Isabel; Simões, Joana; Oliveira, Joaquim; Ferreira, José; Poças, José; da Cunha, José Saraiva; Soares, Jorge; Henriques, Júlia; Mansinho, Kamal; Pedro, Liliana; Aleixo, Maria João; Gonçalves, Maria João; Manata, Maria José; Mouro, Margarida; Serrado, Margarida; Caixeiro, Micaela; Marques, Nuno; Costa, Olga; Pacheco, Patrícia; Proença, Paula; Rodrigues, Paulo; Pinho, Raquel; Tavares, Raquel; de Abreu, Ricardo Correia; Côrte-Real, Rita; Serrão, Rosário; Castro, Rui Sarmento e; Nunes, Sofia; Faria, Telo; Baptista, Teresa; Martins, Maria Rosário O.; Gomes, Perpétua; Mendão, Luís; Simões, Daniel; Abecasis, AnaObjective: To describe and analyze transmitted drug resistance (TDR) between 2014 and 2019 in newly infected patients with HIV-1 in Portugal and to characterize its transmission networks. Methods: Clinical, socioepidemiological, and risk behavior data were collected from 820 newly diagnosed patients in Portugal between September 2014 and December 2019. The sequences obtained from drug resistance testing were used for subtyping, TDR determination, and transmission cluster (TC) analyses. Results: In Portugal, the overall prevalence of TDR between 2014 and 2019 was 11.0%. TDR presented a decreasing trend from 16.7% in 2014 to 9.2% in 2016 (p for-trend = 0.114). Multivariate analysis indicated that TDR was significantly associated with transmission route (MSM presented a lower probability of presenting TDR when compared to heterosexual contact) and with subtype (subtype C presented significantly more TDR when compared to subtype B). TC analysis corroborated that the heterosexual risk group presented a higher proportion of TDR in TCs when compared to MSMs. Among subtype A1, TDR reached 16.6% in heterosexuals, followed by 14.2% in patients infected with subtype B and 9.4% in patients infected with subtype G. Conclusion: Our molecular epidemiology approach indicates that the HIV-1 epidemic in Portugal is changing among risk group populations, with heterosexuals showing increasing levels of HIV-1 transmission and TDR. Prevention measures for this subpopulation should be reinforced.
- HIV-1-transmitted drug resistance and transmission clusters in newly diagnosed patients in Portugal between 2014 and 2019Publication . Pingarilho, Marta; Pimentel, Victor; Miranda, Mafalda N. S.; Silva, Ana Rita; Diniz, António; Ascenção, Bianca Branco; Piñeiro, Carmela; Koch, Carmo; Rodrigues, Catarina; Caldas, Cátia; Morais, Célia; Faria, Domitília; Silva, Elisabete Gomes da; Teófilo, Eugénio; Monteiro, Fátima; Roxo, Fausto; Maltez, Fernando; Rodrigues, Fernando; Gaião, Guilhermina; Ramos, Helena; Costa, Inês; Germano, Isabel; Simões, Joana; Oliveira, Joaquim; Ferreira, José; Poças, José; Cunha, José Saraiva da; Soares, Jorge; Henriques, Júlia; Mansinho, Kamal; Pedro, Liliana; Aleixo, Maria João; Gonçalves, Maria João; Manata, Maria José; Mouro, Margarida; Serrado, Margarida; Caixeiro, Micaela; Marques, Nuno; Costa, Olga; Pacheco, Patrícia; Proença, Paula; Rodrigues, Paulo; Pinho, Raquel; Tavares, Raquel; Abreu, Ricardo Correia de; Côrte-Real, Rita; Serrão, Rosário; Castro, Rui Sarmento e; Nunes, Sofia; Faria, Telo; Baptista, Teresa; Martins, Maria Rosário O.; Gomes, Perpétua; Mendão, Luís; Simões, Daniel; Abecasis, Ana; on behalf of the BESTHOPE Study GroupObjective: To describe and analyze transmitted drug resistance (TDR) between 2014 and 2019 in newly infected patients with HIV-1 in Portugal and to characterize its transmission networks. Methods: Clinical, socioepidemiological, and risk behavior data were collected from 820 newly diagnosed patients in Portugal between September 2014 and December 2019. The sequences obtained from drug resistance testing were used for subtyping, TDR determination, and transmission cluster (TC) analyses. Results: In Portugal, the overall prevalence of TDR between 2014 and 2019 was 11.0%. TDR presented a decreasing trend from 16.7% in 2014 to 9.2% in 2016 (pfor–trend = 0.114). Multivariate analysis indicated that TDR was significantly associated with transmission route (MSM presented a lower probability of presenting TDR when compared to heterosexual contact) and with subtype (subtype C presented significantly more TDR when compared to subtype B). TC analysis corroborated that the heterosexual risk group presented a higher proportion of TDR in TCs when compared to MSMs. Among subtype A1, TDR reached 16.6% in heterosexuals, followed by 14.2% in patients infected with subtype B and 9.4% in patients infected with subtype G. Conclusion: Our molecular epidemiology approach indicates that the HIV-1 epidemic in Portugal is changing among risk group populations, with heterosexuals showing increasing levels of HIV-1 transmission and TDR. Prevention measures for this subpopulation should be reinforced.
- HIV-2 integrase polymorphisms and longitudinal genotypic analysis of HIV-2 infected patients failing a raltegravir-containing regimenPublication . Cavaco-Silva, Joana; Abecasis, Ana; Miranda, Ana Cláudia; Poças, José; Narciso, Jorge; Águas, Maria João; Maltez, Fernando; Almeida, Isabel; Germano, Isabel; Diniz, António; Gonçalves, Maria de Fátima; Gomes, Perpétua; Cunha, Celso; Camacho, Ricardo Jorge
- Increasing prevalence of HIV-1 transmitted drug resistance in Portugal: implications for first line treatment recommendationsPublication . Pingarilho, Marta; Pimentel, Victor; Diogo, Isabel; Fernandes, Sandra; Miranda, Mafalda; Pineda-Pena, Andrea; Libin, Pieter; Theys, Kristof; Martins, M. Rosário O.; Vandamme, Anne-Mieke; Camacho, Ricardo; Gomes, Perpétua; Abecasis, Ana; Portuguese HIV-1 Resistance Study GroupIntroduction: Treatment for All recommendations have allowed access to antiretroviral (ARV) treatment for an increasing number of patients. This minimizes the transmission of infection but can potentiate the risk of transmitted (TDR) and acquired drug resistance (ADR). Objective: To study the trends of TDR and ADR in patients followed up in Portuguese hospitals between 2001 and 2017. Methods: In total, 11,911 patients of the Portuguese REGA database were included. TDR was defined as the presence of one or more surveillance drug resistance mutation according to the WHO surveillance list. Genotypic resistance to ARV was evaluated with Stanford HIVdb v7.0. Patterns of TDR, ADR and the prevalence of mutations over time were analyzed using logistic regression. Results and Discussion: The prevalence of TDR increased from 7.9% in 2003 to 13.1% in 2017 (p < 0.001). This was due to a significant increase in both resistance to nucleotide reverse transcriptase inhibitors (NRTIs) and non-nucleotide reverse transcriptase inhibitors (NNRTIs), from 5.6% to 6.7% (p = 0.002) and 2.9% to 8.9% (p < 0.001), respectively. TDR was associated with infection with subtype B, and with lower viral load levels (p < 0.05). The prevalence of ADR declined from 86.6% in 2001 to 51.0% in 2017 (p < 0.001), caused by decreasing drug resistance to all antiretroviral (ARV) classes (p < 0.001). Conclusions: While ADR has been decreasing since 2001, TDR has been increasing, reaching a value of 13.1% by the end of 2017. It is urgently necessary to develop public health programs to monitor the levels and patterns of TDR in newly diagnosed patients.
- Molecular epidemiology of HIV-1 infected migrants followed up in Portugal: trends between 2001–2017Publication . Pimentel, Victor; Pingarilho, Marta; Alves, Daniela; Diogo, Isabel; Fernandes, Sandra; Miranda, Mafalda; Pineda-Peña, Andrea-Clemencia; Libin, Pieter; Martins, M. Rosário O.; Vandamme, Anne-Mieke; Camacho, Ricardo; Gomes, Perpétua; Abecasis, AnaMigration is associated with HIV-1 vulnerability. Objectives: To identify long-term trends in HIV-1 molecular epidemiology and antiretroviral drug resistance (ARV) among migrants followed up in Portugal Methods: 5177 patients were included between 2001 and 2017. Rega, Scuel, Comet, and jPHMM algorithms were used for subtyping. Transmitted drug resistance (TDR) and Acquired drug resistance (ADR) were defined as the presence of surveillance drug resistance mutations (SDRMs) and as mutations of the IAS-USA 2015 algorithm, respectively. Statistical analyses were performed. Results: HIV-1 subtypes infecting migrants were consistent with the ones prevailing in their countries of origin. Over time, overall TDR significantly increased and specifically for Non-nucleoside reverse transcriptase inhibitor (NNRTIs) and Nucleoside reverse transcriptase inhibitor (NRTIs). TDR was higher in patients from Mozambique. Country of origin Mozambique and subtype B were independently associated with TDR. Overall, ADR significantly decreased over time and specifically for NRTIs and Protease Inhibitors (PIs). Age, subtype B, and viral load were independently associated with ADR. Conclusions: HIV-1 molecular epidemiology in migrants suggests high levels of connectivity with their country of origin. The increasing levels of TDR in migrants could indicate an increase also in their countries of origin, where more efficient surveillance should occur.
- Phylogeography of hepatitis B virus : the role of Portugal in the early dissemination of HBV worldwidePublication . Marcelino, Rute; Ezeonwumelu, Ifeanyi Jude; Janeiro, André; Mimoso, Paula; Matos, Sónia; Briz, Veronica; Pimentel, Victor; Pingarilho, Marta; Marinho, Rui Tato; Marcelino, José Maria; Taveira, Nuno; Abecasis, AnaIn Portugal, the genetic diversity, origin of HBV and the Portuguese role in the dissemination of HBV worldwide were never investigated. In this work, we studied the epidemic history and transmission dynamics of HBV genotypes that are endemic in Portugal. HBV pol gene was sequenced from 130 patients followed in Lisbon. HBV genotype A was the most prevalent (n = 54, 41.5%), followed by D (n = 44, 33.8%), and E (n = 32, 24.6%). Spatio-temporal evolutionary dynamics was reconstructed in BEAST using a Bayesian Markov Chain Monte Carlo method, with a GTR nucleotide substitution model, an uncorrelated lognormal relaxed molecular clock model, a Bayesian skyline plot, and a continuous diffusion model. HBV subgenotype D4 was the first to be introduced in Portugal around 1857 (HPD 95% 1699–1931) followed by D3 and A2 a few decades later. HBV genotype E and subgenotype A1 were introduced in Portugal later, almost simultaneously. Our results indicate a very important role of Portugal in the exportation of subgenotypes D4 and A2 to Brazil and Cape Verde, respectively, in the beginning of the XX century. This work clarifies the epidemiological history of HBV in Portugal and provides new insights in the early and global epidemic history of this virus.