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Quina M, Ramos D, Silva C, Pádua E. Diversity of Human T-Lymphotropic Virus Type 1 Cosmopolitan Subtype (HTLV-1a) Circulating in Infected Residents in Portugal. AIDS Res Hum Retroviruses 2024; 40:171-180. [PMID: 37462999 DOI: 10.1089/aid.2023.0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023] Open
Abstract
Human T-cell lymphotropic virus type 1 (HTLV-1) prevalence in Portugal is low and mainly affects immigrants from endemic areas where human immunodeficiency virus (HIV) infection represents a public health problem. Despite the majority of HTLV-1-infected individuals remains asymptomatic, severe pathologies may develop after prolonged viral persistence, namely an aggressive form of leukemia. An increased mortality rate and faster progression to death is often related to HTLV-1/HIV coinfection. Nevertheless, studies showed that some antiretrovirals used in HIV treatment lead to a positive immune response against HTLV-1. This study aimed to analyze epidemiological and clinical data, and to assess the diversity of HTLV-1 strains circulating in infected residents diagnosed in the Portuguese national reference laboratory between 2010 and 2021. Long terminal repeat and env proviral sequences derived from 20 individuals were used to generate phylogenetic trees along with multiples reference sequences from different geographic origins retrieved from the database. Three samples belong to Portuguese natives and 17 belong to immigrants: 15 from several countries of Africa, 1 from South America, and 1 from Europe; 6 patients (30%, mean age 40.3 years) showed HTLV-1-related diseases, and 6 (30%, mean age 45.2 years) were coinfected with HIV/AIDS. The results show that the Cosmopolitan subtype is circulating in Portugal, with 10 sequences being classified as subgroup A, that include Portuguese and natives from S. Tomé and Príncipe with a mean age of 39.4 years, and 10 sequences that segregated into the Senegal cluster derived from natives born in Guinea-Bissau with a mean age of 43.5 years. A high proportion of HTLV-1-related diseases and HIV/AIDS coinfection was observed. Risk behavior practices and the absence of specific control measures, including diagnostic and treatment, may contribute to a silent dissemination of a broad diversity of HTLV-1 strains and, therefore, the increased rate of progression to debilitating diseases. In this manner, an early diagnostic and a molecular surveillance of HTLV-1 transmission remains necessary in Portugal.
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Affiliation(s)
- Miriam Quina
- Reference Laboratory of HIV and Hepatitis B and C, Infectious Diseases Department, National Institute of Health, Lisbon, Portugal
| | - Diogo Ramos
- Reference Laboratory of HIV and Hepatitis B and C, Infectious Diseases Department, National Institute of Health, Lisbon, Portugal
| | - Carolina Silva
- Reference Laboratory of HIV and Hepatitis B and C, Infectious Diseases Department, National Institute of Health, Lisbon, Portugal
| | - Elizabeth Pádua
- Reference Laboratory of HIV and Hepatitis B and C, Infectious Diseases Department, National Institute of Health, Lisbon, Portugal
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Ramos D, Pinto M, Sousa Coutinho R, Silva C, Quina M, Gomes JP, Pádua E. Looking at the Molecular Target of NS5A Inhibitors throughout a Population Highly Affected with Hepatitis C Virus. Pathogens 2023; 12:754. [PMID: 37375444 DOI: 10.3390/pathogens12060754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/18/2023] [Accepted: 05/22/2023] [Indexed: 06/29/2023] Open
Abstract
Hepatitis C virus (HCV) is associated with liver damage and an increased progression rate to cirrhosis and hepatocellular carcinoma. In Portugal, it is prevalent in vulnerable populations such as injection drug users (IDU). HCV is characterized by a high intra-host variability, and the selecting driving forces could select variants containing resistance-associated substitutions (RAS) that reduce treatment effectiveness. The main goal of this study was to analyze the sequence variation of NS5A in treatment-naïve IDU. The epidemiological and clinical status of hepatitis C were analyzed, and samples were sequenced by Sanger and Next-Generation sequencing (NGS) to assess RAS and confirm HCV subtypes. Phylogenetic classification was concordant: 1a, 52.4%; 1b, 10.7%; 3a, 20.2%; 4a, 8.3%; 4d, 7.1%; and one 2k/1b recombinant. A 1a/3a mixed infection was detected by NGS. RAS were found in 34.5% (29/84) of samples using Sanger sequencing, while in 42.9% (36/84) using NGS. In sequences from subtypes 1a and 1b, RAS K24R, M28V, Q30H/R, H58D/P/Q/R, and RAS L31M and P58S were detected, respectively. In subtype 3a, RAS A30S/T, Y93H and polymorphisms in position 62 were identified. Additionally, RAS P58L was detected in genotype 4. The strategy used for the molecular survey of baseline HCV resistance is of particular importance to achieve treatment effectiveness and contribute to the elimination of hepatitis C.
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Affiliation(s)
- Diogo Ramos
- Reference Laboratory of HIV and Hepatitis B and C, Department of Infectious Diseases, National Institute of Health, Av. Padre Cruz, P-1649-016 Lisbon, Portugal
| | - Miguel Pinto
- Genomics and Bioinformatics Unit, Department of Infectious Diseases, National Institute of Health, Av. Padre Cruz, P-1649-016 Lisbon, Portugal
| | - Rodrigo Sousa Coutinho
- Association Ares do Pinhal, Association for the Rehabilitation of Drug Addicts, Low-Threshold Methadone Substitution Program, R. José Inácio Andrade, Loja 2-A6-10B Quinta do Lavrado, P-1900-418 Lisbon, Portugal
| | - Carolina Silva
- Reference Laboratory of HIV and Hepatitis B and C, Department of Infectious Diseases, National Institute of Health, Av. Padre Cruz, P-1649-016 Lisbon, Portugal
| | - Miriam Quina
- Reference Laboratory of HIV and Hepatitis B and C, Department of Infectious Diseases, National Institute of Health, Av. Padre Cruz, P-1649-016 Lisbon, Portugal
| | - João Paulo Gomes
- Genomics and Bioinformatics Unit, Department of Infectious Diseases, National Institute of Health, Av. Padre Cruz, P-1649-016 Lisbon, Portugal
| | - Elizabeth Pádua
- Reference Laboratory of HIV and Hepatitis B and C, Department of Infectious Diseases, National Institute of Health, Av. Padre Cruz, P-1649-016 Lisbon, Portugal
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Simões C, Pádua E, Mendes A, Esteves A, Parreira R, Piedade J. Genetic diversity and drug resistance profiles of human immunodeficiency virus type 1 (HIV-1) strains infecting pregnant women in the Greater Lisbon. J Clin Virol 2016. [DOI: 10.1016/j.jcv.2016.08.182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Pádua E, Avó AP, Almeida C, Água Doce I, Cortes Martins H. [Assessment of Hepatitis C Virus Diversity in Addition to the Frequency of Genotypes in Samples Analyzed Between 2009 and 2014 at the Reference Laboratory of National Health Institute Dr. Ricardo Jorge]. ACTA MEDICA PORT 2015; 28:695-701. [PMID: 26849752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 06/29/2015] [Indexed: 06/05/2023]
Abstract
INTRODUCTION The identification of genotypes was essential for the prognosis and treatment of hepatitis C virus chronic patients in recent years. The aims of the study were to know the frequency of genotypes diagnosed in the last six years at the laboratory, and reveal the contribution of an in-house assay for molecular characterization of viruses. MATERIAL AND METHODS The genotyping of hepatitis C virus by LiPA was performed in 923 samples, mostly from male individuals. The subtyping of hepatitis C virus by an in-house assay to target regions in the Core/E1 and/or NS5B was performed in 112 samples. RESULTS We observed a high prevalence of genotype 1 (56.6%), with a frequency of subtype 1a four times higher compared to 1b. All cases of genotype 3 (27.5%) were subtype 3a. For the cases of genotype 4 (12.9%), it were identified subtypes 4a (65.5%), 4d (31%), 4b (1.7%) and 4c (1.7%). Recombinants intragenotype 2, the RF1_2k/1b, and mixed infections, were also identified. DISCUSSION The most prevalent subtypes (1a and 3a) obtained are usually described in injecting drug users. Although most of the samples analysed match to inmates (78.4%), we cannot exclude any possible risk behaviors associated with illicit drug use. CONCLUSIONS The high prevalence of subtype 1a, the frequency and diversity of genotype 4, and the identification of recombined virus suggest modification of the molecular pattern of hepatitis C virus infection described in the past. The in-house assay proved to be useful for the correct classification of hepatitis C virus and improving knowledge about the diversity of virus circulating in the country.
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Affiliation(s)
- Elizabeth Pádua
- Laboratório Nacional de Referência de Infeções Sexualmente Transmissíveis -VIH e vírus da hepatite B e C. Departamento de Doenças Infeciosas. Instituto Nacional de Saúde Dr. Ricardo Jorge. Lisboa. Portugal
| | - Ana Patricia Avó
- Laboratório Nacional de Referência de Infeções Sexualmente Transmissíveis -VIH e vírus da hepatite B e C. Departamento de Doenças Infeciosas. Instituto Nacional de Saúde Dr. Ricardo Jorge. Lisboa. Portugal
| | - Catarina Almeida
- Laboratório Nacional de Referência de Infeções Sexualmente Transmissíveis -VIH e vírus da hepatite B e C. Departamento de Doenças Infeciosas. Instituto Nacional de Saúde Dr. Ricardo Jorge. Lisboa. Portugal
| | - Ivone Água Doce
- Laboratório Nacional de Referência de Infeções Sexualmente Transmissíveis -VIH e vírus da hepatite B e C. Departamento de Doenças Infeciosas. Instituto Nacional de Saúde Dr. Ricardo Jorge. Lisboa. Portugal
| | - Helena Cortes Martins
- Laboratório Nacional de Referência de Infeções Sexualmente Transmissíveis -VIH e vírus da hepatite B e C. Departamento de Doenças Infeciosas. Instituto Nacional de Saúde Dr. Ricardo Jorge. Lisboa. Portugal
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Pádua E, Avó AP, Almeida C, Água Doce I, Cortes Martins H. Conhecer a Diversidade do Vírus da Hepatite C para Além da Frequência dos Genótipos em Amostras Analisadas entre 2009 e 2014 no Laboratório de Referência do Instituto Nacional de Saúde Dr. Ricardo Jorge. ACTA MEDICA PORT 2015. [DOI: 10.20344/amp.6257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
<strong>Introduction:</strong> The identification of genotypes was essential for the prognosis and treatment of hepatitis C virus chronic patients in recent years. The aims of the study were to know the frequency of genotypes diagnosed in the last six years at the laboratory, and reveal the contribution of an in-house assay for molecular characterization of viruses.<br /><strong>Material and Methods:</strong> The genotyping of hepatitis C virus by LiPA was performed in 923 samples, mostly from male individuals. The subtyping of hepatitis C virus by an in-house assay to target regions in the Core/E1 and/or NS5B was performed in 112 samples.<br /><strong>Results:</strong> We observed a high prevalence of genotype 1 (56.6%), with a frequency of subtype 1a four times higher compared to 1b. All cases of genotype 3 (27.5%) were subtype 3a. For the cases of genotype 4 (12.9%), it were identified subtypes 4a (65.5%), 4d (31%), 4b (1.7%) and 4c (1.7%). Recombinants intragenotype 2, the RF1_2k/1b, and mixed infections, were also identified.<br /><strong>Discussion:</strong> The most prevalent subtypes (1a and 3a) obtained are usually described in injecting drug users. Although most of the samples analysed match to inmates (78.4%), we cannot exclude any possible risk behaviors associated with illicit drug use.<br /><strong>Conclusions: </strong>The high prevalence of subtype 1a, the frequency and diversity of genotype 4, and the identification of recombined virus suggest modification of the molecular pattern of hepatitis C virus infection described in the past. The in-house assay proved to be useful for the correct classification of hepatitis C virus and improving knowledge about the diversity of virus circulating in the country.
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Silva T, Cortes Martins H, Coutinho R, Leitão E, Silva R, Pádua E. Molecular characterization of hepatitis C virus for determination of subtypes and detection of resistance mutations to protease inhibitors in a group of intravenous drug users co-infected with HIV. J Med Virol 2015; 87:1549-57. [DOI: 10.1002/jmv.24213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2015] [Indexed: 01/15/2023]
Affiliation(s)
- Tânia Silva
- Department of Infectious Diseases; National Reference Laboratory of HIV and Hepatitis B and C; National Institute of Health; Lisbon Portugal
| | - Helena Cortes Martins
- Department of Infectious Diseases; National Reference Laboratory of HIV and Hepatitis B and C; National Institute of Health; Lisbon Portugal
| | - Rodrigo Coutinho
- Support office for Drug Addicts; Association of Ares do Pinhal; Lisboa Portugal
| | - Emília Leitão
- Support office for Drug Addicts; Association of Ares do Pinhal; Lisboa Portugal
| | - Rui Silva
- Support office for Drug Addicts; Association of Ares do Pinhal; Lisboa Portugal
| | - Elizabeth Pádua
- Department of Infectious Diseases; National Reference Laboratory of HIV and Hepatitis B and C; National Institute of Health; Lisbon Portugal
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Avó AP, Agua-Doce I, Andrade A, Pádua E. Hepatitis C virus subtyping based on sequencing of the C/E1 and NS5B genomic regions in comparison to a commercially available line probe assay. J Med Virol 2013; 85:815-22. [PMID: 23508907 DOI: 10.1002/jmv.23545] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2013] [Indexed: 12/25/2022]
Abstract
Hepatitis C virus (HCV) genotype determination is required in clinical practice to establish the dose and duration of antiviral treatment. Although subtype identification does not impact on current therapy this is changing with new specific inhibitors of HCV enzymes and functions which are becoming available worldwide. These new drugs may yield different antiviral responses and resistance profiles. Accurate classification of HCV genotype and subtype is therefore crucial. An "in-house" method was developed for improving HCV subtyping and the results were compared with a second-generation line probe assay (LiPA) used extensively in Portugal. Phylogenetic analysis was undertaken of the C/E1 and NS5B genomic regions of HCV isolated from 72 prisoners with chronic HCV infection and from reference samples. Although LiPA is considered to be a good method for genotyping, HCV was subtyped in only 47.2% of cases compared with 95.8% of cases by the "in-house" method. Molecular data for both C/E1 and NS5B regions were obtained in 88.9% of the samples. Two out of 23 cases of subtype 1a were misclassified as subtype 1b by LiPA. A putative recombinant like RF1_2k/1b, two potential inter-genotypic recombinants 1b/4a and 3a/4a, and also a potential intra-genotypic recombinant 2q/2k in C/E1 and 2k/2a in NS5B were also identified. The "in-house" method enabled HCV to be subtyped accurately with the detection, in some cases, of recombinant viruses or dual HCV infections. Near full-length genomic analysis to characterize these potential recombinant viruses is planned.
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Affiliation(s)
- Ana Patrícia Avó
- National Reference Laboratory of HIV and Hepatitis B and C, Department of Infectious Diseases, National Institute of Health, Avenue Padre Cruz, Lisbon, Portugal
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Pádua E, Rodés B, Pérez-Piñar T, Silva AF, Jiménez V, Ferreira F, Toro C. Molecular characterization of human T cell leukemia virus type 1 subtypes in a group of infected individuals diagnosed in Portugal and Spain. AIDS Res Hum Retroviruses 2011; 27:317-22. [PMID: 20950257 DOI: 10.1089/aid.2010.0195] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Over the past decade, Portugal and Spain received large numbers of immigrants from HTLV-1 endemic areas. Our aim was to investigate the diversity of subtypes circulating in these two countries and the introduction of new variants. We performed a molecular analysis of HTLV-1 strains in patients diagnosed since 1998. LTR and env proviral sequences from 26 individuals were analyzed to generate phylogenetic trees along with reference HTLV-1 subtypes from several geographic origins. Epidemiological and clinical data were recorded. Most subjects were immigrants (57.7%) from South America and Africa. All isolates belonged to the cosmopolitan A subtype. Most carried the transcontinental subgroup A, but five subjects carried subgroup D and one carried subgroup C, previously unreported in Europe. HTLV strains showed separate clusters linked to the patients' geographic origin. Although subjects with HTLV-1 infection tend not to be engaged in high-risk practices, silent dissemination of a broad diversity of HTLV-1 viruses may still occur.
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Affiliation(s)
- Elizabeth Pádua
- AIDS Reference Laboratory, Infectious Diseases Department of National Institute of Health, Lisbon, Portugal
| | - Berta Rodés
- Infectious Diseases Department, Hospital Carlos III, Madrid, Spain
| | - Teresa Pérez-Piñar
- Infectious Diseases Department, Hospital Carlos III, Madrid, Spain
- UAM, Madrid, Spain
| | - Ana Filipa Silva
- AIDS Reference Laboratory, Infectious Diseases Department of National Institute of Health, Lisbon, Portugal
| | - Victoria Jiménez
- Infectious Diseases Department, Hospital Carlos III, Madrid, Spain
| | - Filipa Ferreira
- Infectious Diseases Department of the National Institute of Health, Porto, Portugal
| | - Carlos Toro
- Microbiology Department, Hospital Carlos III, Madrid, Spain
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Remedios M, Paixao E, Feliciano H, Silva-Graca A, Pádua E. Analysis of longitudinal nef sequence variation throughout HIV-2 infection. Int J Infect Dis 2010. [DOI: 10.1016/j.ijid.2010.02.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Pádua E, Parreira R, Tendeiro R, Nunes B, Castela J, Soares I, Mouzinho A, Reis E, Paixão MT. Potential impact of viral load and genetic makeup of HIV type 1 on mother-to-child transmission: characterization of env-C2V3C3 and nef sequences. AIDS Res Hum Retroviruses 2009; 25:1171-7. [PMID: 19886833 DOI: 10.1089/aid.2009.0103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
HIV-1 mother-to-child transmission (MTCT) was evaluated in terms of the molecular characterization of the env and nef genomic regions and quantification of maternal RNA viral loads. Assignment of viral subtype was achieved by direct sequencing of PCR 1172 products amplified from proviral DNA in 45 HIV-1-nontransmitting mothers (NTM), along with 13 pairs of HIV-1-transmitting mothers (TM) and their infected children (C). Analysis of the env C2V3C3 and nef sequences revealed that subtypes G and B, and their genetic combinations (AG, BG), accounted for over 84.5% of all viruses identified. The genetic structure form envA-nefG was the most commonly observed, with a lower frequency in the NTM (13.3%) compared to the TM (23.1%) group. A greater number of genetic forms was observed among NTM, namely the presence of sequences assigned to subtypes D and F, as well as the intergenetic A/J, and C/U, recombinant forms, along with a mosaic provirus with a complex putative envA-nefEGE genetic structure. No significant differences were found when RNA viral loads were evaluated as a function of the viral subtypes. Nevertheless, a relatively high quantification of HIV-1 RNA was obtained in the NTM group, emphasizing the importance of the compliance and effectiveness of therapeutic schemes to control viral replication and reduce the risk of HIV vertical transmission. V3 sequences displaying features associated with the R5 phenotype dominated in both groups. Both C2V3C3 and Nef's functional domains were conserved during HIV-1 vertical transmission.
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Affiliation(s)
- Elizabeth Pádua
- Laboratório de Referência da SIDA, Instituto Nacional de Saúde, 1649-016 Lisboa, Portugal
| | - Ricardo Parreira
- Unidade de Virologia/UPMM, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, 1349-008 Lisboa, Portugal
| | - Rita Tendeiro
- Laboratório de Referência da SIDA, Instituto Nacional de Saúde, 1649-016 Lisboa, Portugal
| | - Baltazar Nunes
- Observatório Nacional de Saúde, Instituto Nacional de Saúde, 1649-016 Lisboa, Portugal
| | - João Castela
- Maternidade Alfredo da Costa, Rua Viriato, 1069-089 Lisboa, Portugal
| | - Isabel Soares
- Pediatria, Hospital Garcia de Orta, Pragal, 2801-951 Almada, Portugal
| | - Ana Mouzinho
- Infecto de Pediatria, Hospital Santa Maria, 1649-035 Lisboa, Portugal
| | - Eduarda Reis
- Neonatologia, Hospital S. Francisco Xavier, Estrada do Forte do Alto do Duque, 1495-005 Lisboa, Portugal
| | - Maria Teresa Paixão
- Núcleo de Vigilância Epidemiológica das Doenças Transmissíveis, Instituto Nacional de Saúde, 1649-016 Lisboa, Portugal
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Pádua E, Almeida C, Nunes B, Cortes Martins H, Castela J, Neves C, Paixão MT. Assessment of mother-to-child HIV-1 and HIV-2 transmission: an AIDS reference laboratory collaborative study. HIV Med 2009; 10:182-90. [PMID: 19207600 DOI: 10.1111/j.1468-1293.2008.00669.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE A prospective study was carried out to assess HIV-1 and HIV-2 mother-to-child transmission (MTCT) rates in Portugal between 1999 and 2005 by analysing the proportion of diagnosed infected children born to HIV-positive mothers. MATERIALS AND METHODS Serial blood samples were collected from 1315 children at risk of HIV-1 infection, 131 children at risk of HIV-2 infection and six children at risk of both HIV-1 and HIV-2 infections attending 25 Health Institutions. HIV proviral DNA was detected by nested polymerase chain reaction (PCR) and statistical analysis was performed using spss. RESULTS DNA PCR using HIV-1 and HIV-2 long terminal repeat (LTR) primers amplified 92.5% and 75% of maternal HIV infections, respectively. Overall, MTCT occurred in 3.4% [95% confidence interval (CI) 2.5-4.6%] of HIV-1 and 1.5% (95% CI 0.2-5.4%) of HIV-2 mother-child pairs. A significant decrease in HIV-1 MTCT was observed with time, from 7.0% (95% CI 2.6-14.6%) in 1999 to 0.5% (95% CI 0.0-2.5%) in 2005. HIV MTCT was associated with an absence of antiretroviral therapy in infected pregnant women (P<0.0001). Of the 48 infected children (46 with HIV-1 and two with HIV-2), the schedule of blood sample collection was followed for only 26 children. In 14 (53.8%) of those 26 children the infections were diagnosed in the first sample collected before they were 48 h old, suggesting in utero transmission. Despite the national recommendations for antenatal HIV testing, a high overall proportion (22.2% for HIV-1 and 44.3% for HIV-2) of mothers did not access any MTCT prevention measures, mostly because of late diagnosis in pregnancy. A small but significant proportion of HIV-2 infection was found in mothers with no identifiable link with West Africa. CONCLUSION HIV-2 transmission rates are low (1.5% in this study), and this may have led to a lower uptake of interventions, but in the absence of interventions transmission does occur. HIV-1 transmission was also associated with a lack of intervention, mostly as a result of late presentation. Use of primers restricted to a single sequence led to false-negative maternal results in a significant proportion of cases. In part this may have been attributable to very low HIV DNA loads as well as primer template mismatches. HIV infection was not documented in children born to mothers with negative HIV DNA PCR results.
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Affiliation(s)
- E Pádua
- AIDS Epidemic Reference Laboratory, National Institute of Health, Lisbon, Portugal
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Parreira R, Monteiro F, Pádua E, Piedade J, Venenno T, Paixão MT, Esteves A. Natural polymorphisms of HIV type 2 pol sequences from drug-naive individuals. AIDS Res Hum Retroviruses 2006; 22:1178-82. [PMID: 17147507 DOI: 10.1089/aid.2006.22.1178] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Until today, the susceptibility of human immunodeficiency virus type 2 (HIV-2) to protease and nucleosidic reverse-transcriptase inhibitors (PI and NRTI, respectively) has not been clearly documented. In this report we studied HIV-2 proviral sequences (n = 30) from drug-naive patients. Our results revealed that several amino acid positions in the protease and reverse transcriptase coding sequence harbored residues that have been associated with drug resistance in HIV-1-infected patients. In particular, the M46I substitution in the protease was detected in 90% of the sequences analyzed, which, together with the other substitutions identified, may indicate a reduced susceptibility of HIV-2-infected drug-naive patients to PI. Furthermore, interpretation of genotypic data with four available algorithms, developed for interpretation of HIV-1 sequence data, suggested nonoverlapping profiles of drug resistance.
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Affiliation(s)
- Ricardo Parreira
- Unidade de Virologia/Unidade de Parasitologia e Microbiologia Médicas, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, P-1349-008 Lisboa, Portugal.
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Silva AF, Almeida C, Martins HC, Coutinho R, Leitão E, Silva R, Paixão MT, Pádua E. Prevalence and molecular characterization of human T cell leukemia virus type 2 in a group of intravenous drug users coinfected with HIV type 1 in Portugal. AIDS Res Hum Retroviruses 2005; 21:249-55. [PMID: 15943566 DOI: 10.1089/aid.2005.21.249] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human T cell lymphotropic virus type 2 infections can be found in the large urban areas of the United States and Europe, where Spain and Italy are the most affected countries. The population most affected by the epidemic is characterized by high-risk behavior groups, mainly the sharing of needles between intravenous drug users (IDUs) with contaminated cellular blood products. It is also described that HTLV-2 infection appears as a coinfection with HIV-1. We have selected samples corresponding to 583 IDUs infected with HIV and screened for the presence of HTLV-1/2 antibodies. We have performed the molecular characterization of HTLV-2 in three confirmed positive cases on the basis of the long terminal repeat region. We can observe the Portuguese sequences (PortHl, PortNn, and PortVs) in the HTLV-2b cluster, grouping with the Spanish sequences, showing close phylogenetic relatedness. We may assume that HTLV-2 infection was introduced in Portugal from Spain. These results update previous reports that mentioned Portugal as being free of HTLV- 2 infections, and allow the identification of the subtype that is present, giving a first-hand description of the prevalence of HTLV-2 infection in a particular high-risk behavior group and justifying the importance of epidemiological surveillance in order to prevent dissemination of the infection.
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Affiliation(s)
- Ana Filipa Silva
- Laboratório de Referência da SIDA/Centro de Virologia, Instituto Nacional de Saúde, P-1649-016 Lisbon, Portugal
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Parreira R, Pádua E, Piedade J, Venenno T, Paixão MT, Esteves A. Genetic analysis of human immunodeficiency virus type 1nef in portugal: Subtyping, identification of mosaic genes, and amino acid sequence variability. J Med Virol 2005; 77:8-16. [PMID: 16032733 DOI: 10.1002/jmv.20408] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Extending our previous genetic characterization of human immunodeficiency virus type 1 (HIV-1) strains circulating in Portugal, we here report the first phylogenetic and putative amino acid sequence variability analyses of nef accessory gene. Viral sequences (n = 53) were amplified by nested PCR from proviral DNA purified from peripheral blood mononuclear cells of HIV-1 infected individuals (n = 49). Phylogenetic inference analysis demonstrated a distribution of the viral sequences between subtypes A (sub-subtype A1), B, D, F (sub-subtype F1), G, H, and J, with subtypes G and B accounting altogether for more than half of the genotypes found. A significant number of the proviral DNA sequences analyzed (18.4%) were shown to correspond to intragenic nef recombinants, with the majority having the typical CRF02_AG nef structure. In addition, three novel intragenic recombinant structures were found (B/G/B, CRF02_AG/H, and D/G). From phylogenetic analysis, it was concluded that part of the non-recombinant nef genes might have actually been amplified from mosaic viruses: CRF06_cpx, CRF14_BG, and a new envA/nefJ recombinant. While comparing all the putative Nef sequences, significant amino acid sequence variability was observed. However, most of the described nef functional motifs were relatively well conserved in the majority of the sequences analyzed and numerous amino acid changes fell outside these regions. The results presented unambiguously endorse the high level of complexity of HIV-1 epidemics in Portugal.
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Affiliation(s)
- Ricardo Parreira
- Unidade de Virologia, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Lisboa, Portugal.
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