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Adult T-cell leukemia/lymphoma (ATLL) is an hematological disease caused by human T-cell lymphotropic virus type 1 (HTLV-1) that develops after 20 years of incubation preferentially when the infection is acquired by vertical transmission. In cases of transmission by transfusion or organ transplant, this time is reduced from 3 months to 3 years. Acute ATLL is difficult to diagnose because it is unusual and has a rapid progression to death. In the Argentine Northwest, where the virus is endemic, ATLL is more frequent, however it is also detected continuously in the rest of the country. The treatment of choice, in the first instance, is the combined use of antivirals. We present a case of acute ATLL developed in a 59-year-old man from Santiago del Estero from which intrafamilial transmission of HTLV-1 infection was identified.

Human T-lymphotropic virus type 1 (HTLV-1) is a neglected retrovirus distributed worldwide and the ethiological agent of several pathologies, such as adult T-cell leukemia/lymphoma (ATLL), a chronic myelopathy known as HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) and infective dermatitis associated with HTLV-1 (IDH). HTLV-1 presents tropism for CD4+ T cells and induces deregulation of the cytokine profile. IDH is a severe, chronic superinfected eczema generally associated with Staphylococcus aureus and/or Streptococcus beta haemolyticus infection that responds partially to antibiotic therapy but prompt recurrence develops upon treatment withdrawal. IDH could be a risk factor for progression toward both HAM/TSP and ATLL and, similarly to other diseases associated with HTLV-1, it is sub-diagnosed particularly in non-endemic areas. Here, we present a case of IDH in a young boy living in Buenos Aires with symptoms since 2010, at the age of 5. HTLV-1 infection was suspected and confirmed in 2016. The patient exhibited chronic dermatosis with exudative eruption involving mainly the scalp, retroauricular regions, neck and abdomen. Clinical evaluations, routine laboratory tests, full blood count, and HTLV-1 diagnosis for this case are included.

Human T-lymphotropic virus 1/2 (HTLV-1/2), hepatitis B virus (HBV), and hepatitis D virus (HDV) share transmission routes. Argentina shows low prevalence of HTLV-1/2, HBV, and HDV infections; however, this situation may vary according to the geographic region and group studied. The aim of this study was to estimate the prevalence of HBV and HDV infections and detect both viral genotypes in HTLV-1/2 individuals from Argentina. A total of 202 HTLV-1/2 confirmed samples (blood donors [BD] and individuals with risk factors for HTLV-1/2 [RF]) were tested for HBsAg and total anti-HBc by enzyme-linked immunosorbent assay. All reactive samples for some HBV markers were analyzed for HBV DNA characterization and HDV serological and molecular analysis. Total prevalence was 1.5% for HBsAg and 6.4% for anti-HBc. Prevalence was 23.1% for anti-HDV in all HBV-reactive samples. No significant difference was observed for HBV and HDV prevalence within HTLV subtypes. The population study showed that prevalence of anti-HBc was higher in the RF than in the BD population, with no significant differences between them. The HBsAg marker and anti-HDV were only found in RF, showing significant differences when compared to BD. Regarding molecular detection, one sample amplified for HBV DNA and none for HDV RNA. HBV sequence was classified as subgenotype F1b. New and updated background on serological markers of HBV and HDV infection in patients with HTLV-1/2 was provided.

Background Viruses can evade the host's immune response promoting their survival and proliferation by different mechanisms. It has recently been observed that viruses can also manipulate autophagy mechanism/pathway for their own benefit. Autophagy is a conserved catabolic process for intracellular components, such as proteins and organelles, and it is important in maintaining cellular homeostasis. Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of HTLV-1 associated Myelopathy/ Tropical Spastic Paraparesis (HAM/TSP), Adult T-cell Leukemia/Lymphoma (ATLL) and Bronchiectasis. HTLV-1 has been reported to regulate autophagy favoring viral production. Viral protein Tax blocks the fusion of the autophagosome with the lysosome, preventing degradation and increasing the accumulation of autophagosomes. Yet, the role of autophagy in HTLV-1 infection has not been fully described. The aim of this study was to determine if the autophagic state conditions regulate HTLV-1 infection. Results Tax was distributed in specific patterns and spherical structures in infected Jurkat, HeLa and MT2 cell lines. Autophagic flux treatments modified Tax behavior in infected HeLa and MT2 cell lines as analyzed by confocal microscopy and flow cytometry, respectively. Utilizing relative quantification of mRNA by qPCR, the variation of other viral genes was analyzed, observing a similar pattern for each treatment. Conclusions These results provide evidence that the autophagic state is shown to control HTLV-1 infection. In addition, Tax can be observed in spherical structures linked to the plasma membrane which could be involved in promoting viral propagation. By carrying out this research, we hope to elucidate fundamental mechanisms for the propagation of HTLV-1 that would involve the use of the autophagic pathway, providing a potential therapeutic target to prevent the development of pathologies associated with HTLV-1 infection.

Background Human T lymphotropic virus type 1 (HTLV-1) is the etiological agent of HTLV associated myelopathy/ Tropical Spastic Paraparesis (HAM/TSP) and Adult T cell leukemia/lymphoma (ATLL), in around 2–5% of the infected individuals. Host genetic background might play a role in disease progression. Several previous studies across many countries report HLA haplotype to be one such factor. Here, we sequenced HLA-A, -B and -C of 73 individuals by Sequence-Based Typing (SBT), and compared the frequency of different alleles among ATLL patients, HAM/TSP patients, asymptomatic carriers and non-infected individuals in Argentina. Results The frequency of HLA-A, -B and -C alleles largely matched that of the general population in Argentina. We identified HLA-A*02 and HLA-B*35 as associated to protection from ATLL (p = 0.042) and susceptibility to HAM/TSP (p = 0.006), respectively. We also found a strong correlation between high proviral load (PVL) and disease (p = 0.0177), but were unable to identify any particular allele associated with high or low PVL. Conclusions Our results match several previous reports that link HLA-A*02 and protection from disease. However, this is the first study associating HLA-B*35 to susceptibility to disease in HTLV-1, an allele that has been largely associated to different severity factors related to other viral infections, such as Human Immunodeficiency Virus (HIV-1) and Hepatitis B Virus (HBV).

A molecular epidemiological study was conducted in a population of 9422 blood donors in the province of Corrientes, Northeastern Argentina, to determine the prevalence of Human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2), the phylogenetic identification of HTLV-1 and 2 subtypes/subgroups and perform a mutation analysis. Based on the results obtained, it was shown that both HTLV-1 and HTLV-2 are circulating in a low-risk population of Corrientes, although with a similar prevalence to that of non-endemic areas. Phylogenetic studies identified the HTLV-1 Cosmopolitan subtype Transcontinental subgroup (Aa), and the HTLV-2 subtype b. Infected donors reported neither a history of risk factors such as transfusions, intravenous drug use, nor risky or HTLV-1/2 seropositive sexual partners. These results suggest that these viruses were transmitted from mother to child, possibly from generation to generation, and that these strains were introduced into the Caucasian population of this region from ancestors originating from endemic areas of the country either from or through contact with individuals from other countries years ago. Our results demonstrate for the first time the presence of HTLV-1 and HTLV-2 in the province of Corrientes. Moreover, although the province can be considered a non-endemic area, the need to include these retroviruses in a national Public Health program is highlighted, in order to have qualified professionals duly trained to make their diagnosis and provide the necessary information in relation to primary care and patient follow-up. Fil: Borda, Marcelo A.. Instituto de Cardiología de Corrientes Juana F. Cabral; Argentina. Universidad Nacional del Nordeste; Argentina Fil: Svibel, Graciela R.. Universidad Nacional del Nordeste; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Underdiagnosis of chronic infection with the nematode Strongyloides stercoralis may lead to severe disease in the immunosuppressed. Thus, we have set-up a specific and highly sensitive molecular diagnosis in stool samples. Here, we compared the accuracy of our polymerase chain reaction (PCR)-based method with that of conventional diagnostic methods for chronic infection. We also analyzed clinical and epidemiological predictors of infection to propose an algorithm for the diagnosis of strongyloidiasis useful for the clinician. Molecular and gold standard methods were performed to evaluate a cohort of 237 individuals recruited in Buenos Aires, Argentina. Subjects were assigned according to their immunological status, eosinophilia and/or history of residence in endemic areas. Diagnosis of strongyloidiasis by PCR on the first stool sample was achieved in 71/237 (29.9%) individuals whereas only 35/237(27.4%) were positive by conventional methods, requiring up to four serial stool samples at weekly intervals. Eosinophilia and history of residence in endemic areas have been revealed as independent factors as they increase the likelihood of detecting the parasite according to our study population. Our results underscore the usefulness of robust molecular tools aimed to diagnose chronic S. stercoralis infection. Evidence also highlights the need to survey patients with eosinophilia even when history of an endemic area is absent. Fil: Repetto, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Ruybal, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Solana, Maria Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: López, Carlota. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Carlos G. Durand"; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Alba Soto, Catalina Dirney. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: González, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina

Despite the good clinical efficacy of interferon-alpha (IFNα) to treat some types of cancer and viral infections, this biological drug is underused given its severe adverse effects and high dosing parenteral regimens. Aiming to achieve a breakthrough in therapy with IFNα, this work reports for the first time on the design and full characterization of a novel nanomedicine of IFNα-2b-loaded chitosan nanoparticles (IFN-CT NPs) for oral delivery. IFN-CT NPs produced by ionotropic gelation, encapsulating approximately 100% of the drug, showed a size of 36 ± 8 nm, zeta potential of +30 mV (dynamic light scattering), and spherical morphology (transmission electron microscopy). The antiviral activity of IFN-CT NPs in vitro was comparable to that of commercial IFNα. Remarkably, both treatments stimulated the expression of IFN response genes to a similar extent in both noninfected and infected cells with Human Lymphotropic-T Virus type 1. Finally, oral administration of IFN-CT NPs (0.3 MIU) to CF1 mice showed detectable levels of IFNα in plasma after 1 h, whereas no IFNα was detected with a commercial formulation. These results are encouraging and open a new avenue for the administration of this biological drug in a minimally invasive, safer, and more patient-compliant way.

Introduction: Soft-tissue sarcomas account for 0.7 % of all malignant tumors, with an incidence rate of 3 per 100,000 persons/year. The Undifferentiated Pleomorphic Sarcoma (UPS) with giant cells, a high grade tumor of soft tissue, is very unusual, especially in young adults before the age of 40. Human T-cell lymphotropic virus type-1 (HTLV-1) is a human retrovirus, classified as group 1 human carcinogens by The International Agency for Research on Cancer (IARC), that causes an aggressive malignancy known as adult T-cell lymphoma/leukemia (ATLL) and a progressive chronic inflammatory neurological disease named HTLV-1 associated myelopathy/ tropical spastic paraparesis (HAM/TSP). HTLV-1 causes accumulation of genetic mutations in the host genome that could contribute to cellular transformation, one of the oncogenic features of HTLV-1.Case report: We describe a case of a young woman with UPS who suffered from HAM/TSP with 3 years of evolution. In 2013, the patient started with neurological symptoms: weakness in the legs and bladder dysfunction. One year later, the patient developed a mild paraparesis in both extremities, anti-HTLV-1 antibodies were detected in plasma and in cerebrospinal fluid (CSF), and HAM/TSP was confirmed. In November 2015, a benign ganglion cyst was firstly suspected without intervention and by March 2016 a sarcoma was diagnosed. Three weeks after surgical resection, the tumor aroused in deep tissue and behaved aggressively, implicating a curative wide resection of the fibula, joint reconstruction and soft tissue graft. Histopathological examination confirmed UPS with giant cells.Concluding remarks: The unapparent subclinical immunodeficiency state due to HTLV-1 infection deserves to be considered in order to carefully monitor the possibility of developing any type of cancer. Besides, reaching an accurate and timely diagnosis of UPS can be challenging due to the difficulty in diagnosis/classification and delayed consultation. In this particularly case, considering the high grade of UPS and the progressive invalidating myelopathy caused by HTLV-1, treatment should be carefully evaluated to positively impact on the patient´s life expectancy. Fil: Lupo, Sergio. Universidad Nacional de Rosario; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Cánepa, Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Santini Araujo, Eduardo Héctor. Laboratorio de Patología Ortopédica; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Hepatitis B virus (HBV) is a worldwide public health concern. The circulation of strains carrying mutations in the viral proteins implies both clinical and therapeutics challenges. HBV complete genomes (HBV-CGs) were reported from injecting drug users and HBV chronically infected patients from Argentina—including Amerindians—although no studies were conducted in blood donors. Here, we described HBV-CG sequences from the latter population. Some of the HBV sequences classified as B2 and C2 subgenotypes clustering together with Asian isolates, while others, such as D3, F1b, and F4, were homologous to European and Latin America sequences. New substitutions for all analyzed open reading frames and changes in the HBsAg hydrophobicity profiles were detected. Several HBV-CG subgenotypes are described for the first time in this population. Mutations observed in X, PreS, and P proteins have been associated with advanced liver disease, hepatocellular carcinoma, and/or natural resistance to nucleos(t)ide antiviral treatment. It deserves to be highlighted that these substitutions were detected in a population without epidemiological risk factors for viral infection, and most importantly, without any previous antiviral treatment (natural resistance). Regarding the remaining mutations, further research is warranted in order to determine their clinical and therapeutics relevance. Fil: Delfino, Cecilia María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Pedrozo, Williams René. Provincia de Misiones. Banco de Sangre Central; Argentina Fil: Malan, R.. Provincia de Misiones. Banco de Sangre Central; Argentina Fil: Blejer, Jorgelina L.. Fundación Favaloro; Argentina Fil: Oubiña, Jose Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Mathet, Veronica Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina

El objetivo de este trabajo fue estimar la prevalencia de Treponema pallidum, Trypanosoma cruzi y virus de la inmunodeficiencia humana (HIV-1) en 5 comunidades originarias de Argentina. Para ello, se realizó un estudio retrospectivo en 857 individuos (112 kollas, 298 mbyá-guaraníes, 79 sagua huarpes, 368 wichis) desde el 2007 hasta el 2010. Se realizó el diagnóstico completo para T. pallidum, T. cruzi y HIV-1. En todas las comunidades se confirmaron infecciones por T. pallidum y T. cruzi con una prevalencia total del 4,2 y del 16,8%, respectivamente. Aunque no se detectó HIV-1, sífilis y Chagas, representan un desafío para el sistema de salud, teniendo que reforzarse las estrategias de salud pública teniendo en cuenta el aislamiento socio-económico que sufren estas poblaciones. The objective of this study was to estimate the prevalence of Treponema pallidum, Trypanosoma cruzi and Human immunodeficiency virus 1 (HIV-1) in five Amerindian populations of Argentina. A retrospective study was conducted among 857 Amerindian populations (112 Kollas, 298 Mbyá-guaraníes, 79 Sagua Huarpes, 368 Wichis) from 2007 to 2010. Screening and confirmation of T. pallidum, T. cruzi and HIV-1 were performed. T. pallidum and T. cruzi infections were detected in all communities with an overall prevalence rate of 4.2% and 16.8%, respectively. Although HIV was not detected, syphilis and Chagas’ disease represent a challenge for the health care system and the reinforcement of public health strategies is necessary considering the socioeconomic isolation of these populations. Fil: Eirin, Maria Emilia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Delfino, Cecilia María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Pedrozo, Williams René. Provincia de Misiones. Banco de Sangre Central; Argentina Fil: Malan, Richard. Provincia de Misiones. Banco de Sangre Central; Argentina Fil: Puca, Alberto. Laboratorio de Bioquímica "A. A. Puca"; Argentina Fil: de Rissio, Ana María. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina Fil: Espejo, Rogelio. Provincia de San Juan. Ministerio de Salud. Hospital Público "Dr. Guillermo Rawson". Laboratorio Central; Argentina Fil: Gallo Vaulet, Maria Lucia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Bioquímica Clínica; Argentina Fil: Rodríguez Fermepin, Marcelo. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Bioquímica Clínica; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Human T-lymphotropic virus subtype b (HTLV-2b) infection has been described among aborigines from Northern Argentina, while HTLV-2a has been described in an injecting drug user (IDU) from a Central region, similar to the situation in Spain, the United States, and Brazil. In this study, 22 of the 26 strains analyzed from blood donors and HIV-1+ individuals were HTLV-2b (84.6%) clustering with Amerindian references, while 4 HIV-1+ (15.4%) were HTLV-2a. HTLV-2a sequences were closely related to Brazilian references in contrast to the previous Argentinean IDU strain that clustered with Africans and Amerindians from North America. In summary, these findings show that HTLV-2b is the major strain circulating in an urban population of Argentina. HTLV-2a/b could have been introduced from endemic South American countries such as Brazil and because of contact with other populations such as IDUs from Europe despite its introduction due to the increasing internal migration of aborigines to large urban centers. Considering this results and recent data about the dissemination of HTLV-1 in residents of Buenos Aires city, new studies among non-at-risk groups for HTLV-1/2 infection should be performed. © Copyright 2012, Mary Ann Liebert, Inc. 2012. Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Eirin, Maria Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Delfino, Cecilia María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Weissenbacher, Mercedes Crecencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Background Hepatitis B virus infection is frequent among Amerindians. In Argentina HBV genotypes A, B, C, D, E, F and H were described in different populations, while some cases of occult hepatitis B infection (OBI) were reported in human immunodeficiency virus (HIV) coinfected patients. Objective To determine the prevalence, genetic diversity of HBV and to analyze the deduced amino acid sequence of both S and viral polymerase (P) genes among Amerindians of Argentina. Study design A cross-sectional study including 561 individuals belonging to distinct ethnic groups, the Mbya-guarani (MG), the Kolla (K), the Sagua-Huarpe (SH) and the Wichi (W) was performed. Results The prevalence of HBsAg was 1.7% and 1.4% for the MG and SH, respectively, while anti-HBc was detected in all communities. HBV DNA of S/P and preCore-Core genomic regions were amplified by nested polymerase chain reaction in 59 reactive samples for anti-HBc total Ig and/or HBsAg. Of them, thirteen exhibited detectable HBV DNA, eleven of which were identified as OBI. Genotype F was predominant in the MG community with co-circulation of subgenotypes F4, F1b, A2 and D3, while subgenotype C2 prevailed within the SH community. All cases exhibited the polymorphism rtL217R within the RT domain associated to resistance to adefovir. Mutations rtD206E and rtV207I associated with lamivudine resistance were found in two MG and three SH respectively. Other new substitutions were described within the P sequence. Conclusions This study shows for the first time the predominance of OBI, HBV subgenotypes and natural variants in Amerindians from Argentina.

El Virus Linfotrópico T Humano tipo 1 (HTLV-1), primer oncorretrovirus humano descubierto, es el causante etiológico de la leucemia de células T del adulto (ATL) y de la mielopatía asociada al HTLV-1 o paraparesia espástica tropical (HAM/TSP). Es endémico en distintas partes del mundo, inclusive en el noroeste argentino, donde ambas enfermedades fueron detectadas. El HTLV-2, no tiene un rol etiológico definido, si bien ha sido asociado con síndromes neurológicos similares a la HAM/TSP. Ambos virus son endémicos en comunidades originarias del continente americano, tribus de Africa y poblaciones en riesgo. Ambos retrovirus se transmiten por vía sexual, parenteral y de madre a hijo. El objetivo de este trabajo fue determinar la seroprevalencia de HTLV-1/2 en una población de donantes de sangre de la provincia de Misiones. Se analizaron 6912 donaciones de sangre recibidas en el Banco de Sangre Central de la Provincia de Misiones durante 2008. La detección de anticuerpos se realizó por ELISA y aglutinación de partículas, y las muestras reactivas fueron confirmadas por Western Blot. Del total de muestras, 5 resultaron seropositivas con una prevalencia final de 0.00072. De ellas, una era HTLV, tres HTLV-1 y una HTLV-2 positiva. Los donantes positivos provenían de Posadas, Eldorado y Oberá, sin antecedentes de riesgo. Este estudio demuestra la presencia de HTLV-1/2 en donantes de sangre de Misiones, con cifras similares a las notificadas en donantes de sangre de zonas no endémicas.Human T-cell Lymphotropic viruses type 1 (HTLV-1), the first human oncoretrovirus to be discovered, is the etiologic agent of Adult T-cell Leukemia (ATL) and HTLV-1 Associated Mielopathy or Tropical Spastic Paraparesis (HAM/TSP). It is endemic worldwide, including the North of Argentina where both associated diseases have also been detected. No etiologic role has been described for HTLV-2, although it has been associated with HAM/TSP-like neurologic syndromes. Both retroviruses are endemic in native populations of The Americas, Africa and at-risk populations. They are transmitted through sex contact, parenterally and from mother to child. The aim of this study was to estimate the seroprevalence of HTLV-1/2 in a blood donor population from Misiones province. A total of 6912 accepted blood donations in 2008 were analyzed. HTLV-1/2 screening was performed with ELISA and particle agglutination, and reactive samples were confirmed by Western Blot. From the total, 5 samples resulted seropositive with a final prevalence of 0.00072. Out of the 5 positive samples, one was an HTLV, three HTLV-1 and one HTLV-2. These blood donors were residents of Posadas, Eldorado and Oberá, with no risk antecedents. This study demonstrates the presence of HTLV-1/2 in a population of Misiones with a prevalence rate similar to those reported among blood donors from non-endemic areas.

Objectives The objective of this study was to estimate the prevalence of human T cell lymphotropic virus (HTLV)-1/2, HIV-1, hepatitis B virus (HBV), Trypanosoma cruzi , Treponema pallidum and Toxoplasma gondii infections and to identify the subtypes/subgroups of HTLV-1/2 among pregnant women (PW) from non-endemic provinces of Argentina. Methods Methods A total of 2403 samples were screened for HTLV-1/2 and confirmed by western blot and PCR. The long terminal repeat (LTR) of HTLV-1 and HTLV-2 were amplified. Phylogenetic analysis was performed by Neighbour Joining by using molecular evolutionary genetics analysis (MEGA) 4.0. Results Among a total of 2403 PW studied, 6 (0.25%) tested positive for HTLV-1/2 (3 HTLV-1 (0.12%) and 3 HTLV-2 (0.12%)). The total prevalence when distributed by province was 0.3% (3/804) for Buenos Aires (BA), 0.4% (1/241) for BA surroundings, 0.1% (1/707) for Neuquen and 1.0% (1/95) for Ushuaia. In San Juan, no PW were HTLV-1/2 positive. The prevalence was similar when compared with rates among blood donors of the same areas and years. The phylogenetic analysis classified one sequence as HTLV-1 aA and one as HTLV-2b. The prevalence of HIV-1, HBV, T cruzi, T pallidum and T gondii was 0.6%, 0.2%, 1.4%, 1.2% and 20.9%, respectively. One case of HTLV-1/HIV-1 and one of HTLV-2/HIV-1 co-infection were detected. Conclusions HTLV-1/2, which have been associated with different diseases, are circulating among PW of Argentina, even in non-endemic areas. Therefore, testing should be recommended in women who have risk factors for these infections given that the majority of HTLV-1/2 mother to child transmission can be prevented by the avoidance of breast feeding.

In Argentina, current procedures to ensure the safety of the blood supply for transfusion include the serologic detection of specific blood-borne infections. The aim of this study was to evaluate the prevalence and the genetic diversity of hepatitis B virus (HBV) and hepatitis D virus (HDV) in blood donor populations from two distantly located Argentine regions. Data from 56,983 blood donations from the Favaloro Foundation, in the city of Buenos Aires (Central Region), and the Central Blood Bank of Misiones Province (Northeast Region) were analyzed. Samples that were reactive for HBsAg were analyzed for HBV-DNA characterization and HDV serological and molecular analysis. The HBV prevalence was 0.12 % for HBsAg and 1.68 % for anti-HBc antibodies in Buenos Aires, and 0.73 % and 8.55 %, respectively, in Misiones. Seventy-seven HBsAg-reactive samples were analyzed by polymerase chain reaction for HBV-DNA. Subgenotypes A2, B2, C2, F1b and F4 (Buenos Aires) and F1b and D3 (Misiones) were detected. Several mutations within the major hydrophilic region of HBsAg, the reverse transcriptase, the basal core promoter, and the precore/core were detected. HDV genotype 1 was identified in Buenos Aires. This study confirms the circulation of several HBV subgenotypes, as well as known and newly identified variants, and the presence of HDV1 in this population. A thorough investigation has to be carried out to evaluate the clinical importance of some of the documented mutations as well as those detected in the HDV1 case. Fil: Delfino, Cecilia María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Gentile, Emiliano Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Castillo, Amalia Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Cuestas, María Luján. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Pataccini, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Cánepa, Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Malan, Richard. Provincia de Misiones. Banco de Sangre Central; Argentina Fil: Blejer, Jorgelina L.. Fundación Favaloro; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Eirin, Maria Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Pedrozo, Williams René. Provincia de Misiones. Banco de Sangre Central; Argentina Fil: Oubiña, Jose Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Mathet, Veronica Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina

The objective of this study was to estimate the prevalence of human T cell lymphotropic virus (HTLV)-1/2, HIV-1, hepatitis B virus (HBV), Trypanosoma cruzi, Treponema pallidum and Toxoplasma gondii infections and to identify the subtypes/subgroups of HTLV-1/2 among pregnant women (PW) from non-endemic provinces of Argentina.Methods A total of 2403 samples were screened for HTLV-1/2 and confirmed by western blot and PCR. The long terminal repeat (LTR) of HTLV-1 and HTLV-2 were amplified. Phylogenetic analysis was performed by Neighbour Joining by using molecular evolutionary genetics analysis (MEGA) 4.0.Among a total of 2403 PW studied, 6 (0.25%) tested positive for HTLV-1/2 (3 HTLV-1 (0.12%) and 3 HTLV-2 (0.12%)). The total prevalence when distributed by province was 0.3% (3/804) for Buenos Aires (BA), 0.4% (1/241) for BA surroundings, 0.1% (1/707) for Neuquen and 1.0% (1/95) for Ushuaia. In San Juan, no PW were HTLV-1/2 positive. The prevalence was similar when compared with rates among blood donors of the same areas and years. The phylogenetic analysis classified one sequence as HTLV-1 aA and one as HTLV-2b. The prevalence of HIV-1, HBV, T cruzi, T pallidum and T gondii was 0.6%, 0.2%, 1.4%, 1.2% and 20.9%, respectively. One case of HTLV-1/HIV-1 and one of HTLV-2/HIV-1 co-infection were detected.HTLV-1/2, which have been associated with different diseases, are circulating among PW of Argentina, even in non-endemic areas. Therefore, testing should be recommended in women who have risk factors for these infections given that the majority of HTLV-1/2 mother to child transmission can be prevented by the avoidance of breast feeding.

a b s t r a c t Background: Guidelines suggest that all HBsAg-positive patients should be tested for anti-HDV IgG anti- bodies and to confirm active hepatitis D virus (HDV) infection by detection of HDV RNA by reverse transcriptase (RT) polymerase chain reaction (PCR). Objectives: The aim of this study was to determine the serological prevalence and molecular features of HDV within an Amerindian community from Argentina exhibiting positivity for HBsAg and/or anti-HBc total Ig. Study design: Forty-six plasma samples were tested for the detection of total anti-HDV antibodies by ELISA. Concomitantly, a partial RNA region coding for the delta antigen (HDAg) was amplified by RT- nested PCR (RT-nPCR). In silica translation of DNA sequences into the amino acid (aa) sequence of HDAg-S (aa110-195) and HDAg-L (aa110-214) was performed. Results: Out of 46 HDV non-reactive samples by ELISA, 3 were HDV RNA positive by RT-nPCR. These samples were anti-HBc-only positive, 2 of them identified as cases of occult hepatitis B infection (OBI). The 3 cases were HBeAg-negative and showed normal ALT/AST levels. All sequences were ascribed to HDV genotype 1, but exhibited nucleotide differences in HDAg-L coding region, among which, mutations at codons 197 and 201 - reportedly known to promote in vitro an unsuitable interaction with HBsAg - were observed. Conclusions: These results provide evidence of covert HDV infection even among OBI, highlighting the need to reevaluate the currently applied guidelines for HDV diagnostic algorithms, as well as to explore if the observed mutations promote any effect on HDV pathogenesis. © 2012 Elsevier B.V. All rights reserved. 1. Background HDV is a defective virus that requires the helper function of hep- atitis B virus (HBV) for its assembly and transmission. 1 The HDV particle consists of an outer envelope of HBV surface proteins, while the genomic RNA is associated with two isoforms of the delta anti- gen, HDAg-S and HDAg-L. The HDAg-S plays an essential role in transactivating the replication of the HDV RNA, while HDAg-L inter- acts with HBsAg in the assembly of HDV and is a dominant repressor of HDV RNA replication. 2

HTLV-1 is endemic in the Northwest among Kolla natives while Buenos Aires city (BA) is considered as non-endemic. In the last decades, migrations to BA have changed from Europeans to Latin-Americans from countries with endemic focus for HTLV-1 infection (Bolivia, Paraguay, Peru, Brazil, and Chile) and also from different African countries.

Jujuy province, in Northwest Argentina, is known to be endemic for HTLV-1 infection. Moreover, foci of HTLV-1 associated pathologies have also been described in this region. To gain an insight into the current situation of HTLV-1/2 in this endemic area, a seroprevalence and phylogenetic study was performed among a Kolla community from Abra Pampa city and surroundings. Out of 112 individuals, 11 (9.8%) were confirmed as HTLV-1 positive and no HTLV-2 infection was detected. The phylogenetic analysis of the LTR region showed that all the HTLV-1 sequences belonged to the Cosmopolitan subtype a/transcontinental subgroup A, and were closely related to reference sequences from Peru, Argentina, and the South of Brazil (P=0.82). Considering the cultural and historical features of this community and in spite of the mandatory detection of anti-HTLV-1/2 antibodies in blood banks since 2005, it would be important to implement new public health measures focused on decreasing HTLV-1 transmission in this endemic area. Fil: Eirin, Maria Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Jones, Leandro Roberto. Fundación Playa Unión. Estación de Fotobiología Playa Unión; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Dilernia, Darío Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Puca, Alberto A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

In Argentina, current procedures to ensure safety of the blood supply for transfusion include reviewing the records of blood donors with particular attention to the serologic detection of specific blood borne infections. Data of 28,483 blood donations received from January 1, 2003 to December 31, 2008 in a public hospital in Buenos Aires were analyzed. Of the 28,483 blood donations, 7,442 (26.1%) were female donors, 14,582 (51.2%) were younger than 35 years old, and 23,746 (83.4%) were Argentine. Among all, only 285 (1.0%) were voluntary donations. The prevalence of HTLV-1/2 was 0.1% (95% CI 0.063-0.15), being 0.07% for HTLV-1 and 0.03% for HTLV-2. The prevalence of HIV-1 was 0.2% (95% CI 0.110-0.206). No HIV-1/HTLV-1/2 co-infections were detected among volunteer donors. During this study period, data confirm that HTLV-1/2 infection was not endemic in Buenos Aires, and that the prevalence of HTLV-1/2 decreased throughout while HIV-1 was stable. Due to the small number of voluntary donations, we could not conduct comparisons to infection rates in replacement donations. Although there have been several ongoing programs aimed at recruiting voluntary blood donations and changing from mostly replacement donations to an altruistic system of blood donations, Argentina is still far from reaching this objective. Additional efforts are needed in order to increase and assure the quality of blood supply in this country. © 2010 Wiley-Liss, Inc. Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Gendler, Silvina A.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Pascuccio, Susana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Eirin, Maria Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: McFarland, Willi. University of California; Estados Unidos Fil: Page, Kimberly. University of California; Estados Unidos Fil: Carnevali, Luisa. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Murphy, Edward. University of California; Estados Unidos. Blood Systems Research Institute; Estados Unidos Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Human T-cell Lymphotropic viruses type 1 (HTLV-1), the first human oncoretrovirus to be discovered, is the etiologic agent of Adult T-cell Leukemia (ATL) and HTLV-1 Associated Mielopathy or Tropical Spastic Paraparesis (HAM/TSP). It is endemic worldwide, including the North of Argentina where both associated diseases have also been detected. No etiologic role has been described for HTLV-2, although it has been associated with HAM/TSP-like neurologic syndromes. Both retroviruses are endemic in native populations of The Americas, Africa and at-risk populations. They are transmitted through sex contact, parenterally and from mother to child. The aim of this study was to estimate the seroprevalence of HTLV-1/2 in a blood donor population from Misiones province. A total of 6912 accepted blood donations in 2008 were analyzed. HTLV-1/2 screening was performed with ELISA and particle agglutination, and reactive samples were confirmed by Western Blot. From the total, 5 samples resulted seropositive with a final prevalence of 0.00072. Out of the 5 positive samples, one was an HTLV, three HTLV-1 and one HTLV-2. These blood donors were residents of Posadas, Eldorado and Oberá, with no risk antecedents. This study demonstrates the presence of HTLV-1/2 in a population of Misiones with a prevalence rate similar to those reported among blood donors from non-endemic areas.

HTLV-1 Cosmopolitan subtype Transcontinental subgroup A has been described among aboriginal communities from the northwest endemic area of Argentina. Moreover, Transcontinental subgroup A and the Japanese subgroup B were reported among blood donors from the nonendemic central region of the country. We carried out the first HTLV-1 phylogenetic study in individuals residing in Buenos Aires capital city. Phylogenetic analysis performed on the LTR region showed that all 44 new strains clustered within the Cosmopolitan subtype, with 42 (95.4%) belonging to Transcontinental subgroup A. Of them, 20 (45.5%) strains grouped in the large Latin American cluster and 4 (9.1%) in the small Latin American cluster. The majority of them belonged to individuals of nonblack origin, grouped with Amerindian strains. Three (6.8%) were closely related to South African references and two monophyletic clusters including only HIV/HTLV-1 coinfected individuals were observed. Interestingly, two (4.5%) new sequences (divergent strains) branched off from all five known Cosmopolitan subgroups in a well-supported clade. In summary, these findings show that HTLV-1 Cosmopolitan subtype Transcontinental subgroup A is infecting residents of Buenos Aires, a nonendemic area of Argentina, and confirm the introduction of divergent strains in the country. Fil: Eirin, Maria Emilia. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Dilernia, Darío Alberto. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Jones, Leandro Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Pando, María de los Ángeles. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina

The objectives of this study were to estimate the prevalence and characterize the epidemiologic patterns of HTLV-1/2 infections and co-infections with HIV, HBV (hepatitis B), HCV (hepatitis C), and Treponema Pallidum in five different high-risk groups, including injecting drug users (IDUs), female sex workers (FSWs), men who have sex with men (MSM), patients with tuberculosis (TB), and patients attending clinics for sexually transmitted infections (STIs) in Buenos Aires, Argentina. The HTLV-1/2 prevalence was 19.1% (33/173) for IDUs, 2.0% (10/613) for FSWs, 2.1% (4/187) for TB, 1.0% (4/400) for STIs and 0.4% (3/282) for MSM, respectively. Among all groups, the higher percentages of co-infection were HTLV-1/HBV (63%, 17/27) and HTLV-1/HCV (52%, 14/27). Among IDUs, there was a high percentage of co-infection of HTLV-2 with HCV (96.3%, 26/27), HIV (92.6%, 25/27), and HBV (77.8%, 21/27), respectively. In summary, HTLV-1/2 infections appear to be widely distributed among high-risk groups in a nonendemic area of Argentina being the co-infection with HBV and HCV more frequent among IDUs. J. Med. Virol. 79:1914–1920, 2007. © 2007 Wiley-Liss, Inc.

Serological assays for human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2) are widely used in routine screening of blood donors. The aim of this study was to compare the performance of four commercial screening assays for HTLV-1/2 infection frequently used in South America. A total of 142 HTLV-1 and HTLV-2 seropositive and 336 seronegative samples were analyzed by using four commercial tests (BioKit, Vironostika, Murex and Fujirebio). These tests are commonly used for HTLV-1/2 detection in blood banks in Argentina. A nested-PCR was used as the reference standard. The most sensitive tests for HTLV-1/2 were Fujirebio and Biokit (98.6%) followed by Murex (97.2%) and Vironostika (96.5%). The most specific test was Murex (99.7%), followed by Biokit (97.0%), Fujirebio (95.8%), and Vironostika (92.9%). The kappa index of agreement was higher for Murex (κ = 0.97), followed by BioKit (κ = 0.94), Fujirebio (κ = 0.92), and Vironostika (κ = 0.86). The highest index of agreement was shown by Murex test while Vironostika had the lowest performance. Of the four tests evaluated, only the Vironostika assay is approved by the Food and Drug Administration. These results should be considered for choosing the most accurate serological screening assays in order to obtain an optimal efficiency of the current algorithm for HTLV-1/2 diagnosis. Fil: Berini, Carolina Andrea. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina Fil: Susana Pascuccio, M.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Bautista, Christian T.. Asociacion Benefica Prisma Lima; Perú Fil: Gendler, Silvina A.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Eirin, Maria Emilia. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina Fil: Rodriguez, Claudia. Hospital de Alta Complejidad “Presidente Juan D. Perón”; Argentina Fil: Pando, María de los Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina Fil: Biglione, Mirna Marcela. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Sexually transmitted infections (STIs) have shown to enhance the transmission of human immunodeficiency virus (HIV) and to be more common among female commercial sex workers (FSWs). A cross-sectional study was conducted among 625 FSWs in six cities of Argentina in 2000-2002. The seroprevalence of HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), human T-cell lymphotropic virus type I/II, and syphilis was 3.2%, 14.4%, 4.3%, 1.6%, and 45.7%, respectively. Syphilis was associated with older age (≥ 30 years, adjusted odds ratio [AOR] = 2.6 to 4.9), ≥ 10 years in sex work (AOR = 2.2), use of illegal drugs (AOR = 2.1), and a prior history of an STI (AOR = 3.0). HBV and syphilis was the most common co-infection in 44 (7.5%) subjects. FSWs in Argentina are exposed to HIV and other STIs due to high-risk sexual and illegal drug use behavior. Renewed efforts are necessary to intervene effectively in this high-risk population. Fil: Pando, María de los Ángeles. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina Fil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina Fil: Bibini, Mariel. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina Fil: Fernández, Mauro. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina Fil: Reinaga, Elena. Asociación de Mujeres Meretrices de Argentina; Argentina Fil: Maulen, Sergio. Nexo Asociación Civil; Argentina Fil: Marone, Rubén. Nexo Asociación Civil; Argentina Fil: Biglione, Mirna Marcela. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina Fil: Montano, Silvia M.. Naval Medical Research Unit No. 6; Perú Fil: Bautista, Christian T.. Henry M. Jackson Foundation; Estados Unidos Fil: Weissenbacher, Mercedes Crecencia. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina Fil: Sanchez, José L.. Henry M. Jackson Foundation; Estados Unidos Fil: Ávila, María Mercedes. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología. Centro Nacional de Referencia para el Sida; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Conclusion These results correlate with previous studies conducted among IDUs from New York city, Vietnam and Southern Europe where HTLV-IIb was more frequently found. In contrast, IIa is found among IDUs from other regions of the USA, Europe and Brazil. This is the first time in which subtype b is described in Argentina among IDUs. Its presence may be due to migrations of aborigines to big cities and the introduction of drugs in this population. Lately, there was also a high rate of migration and tourism to Argentina, especially from southern Europe and USA, possibly contributing to the spread of HTLV-IIb in our country. Interestingly, the IIa sample described here was found to be related with Brazilian aborigine sequences in contrast to the previous Argentinian IDU which was closer to African isolates. from 2006 International Meeting of The Institute of Human Virology Baltimore, USA. 17–21 November, 2006

Human T-cell lymphotropic virus (HTLV) seroindeterminate cases have been reported among blood donors (BD) and in at-risk populations worldwide, including Argentina. The objective of the present work was to study the presence of HTLV-I/II infection and its association to specific Western blot (WB) patterns among healthy BD and at-risk populations in Argentina. We analyzed 83 HTLV-I/II seroindeterminate WB cases diagnosed among BD (n = 49) and in different at-risk populations (n = 34) for human retroviruses infections. Multiple indeterminate WB patterns were observed. Out of the total, 13.2% (11/83) of the cases were found to be HTLV-I/II positive by nested-PCR (n-PCR), including 13.2% (11/83) HTLV-I and 2.4% (2/83) presenting HTLV-I and -II co-infection. Most of their serological profiles showed reactivity to gag or env codified proteins. Two samples amplified only one of the six analyzed genes (1 HTLV-I pol gene and 1 HTLV-II tax gene). There was no association between the presence of Trypanosoma cruzi infection and an HTLV-I/II indeterminate WB pattern (only 3 of the 83 samples were positive for T. cruzi antibodies). In conclusion, the majority of HTLV-seroindeterminate WB donors lacked HTLV provirus and was thus considered uninfected. However, when seroreactivity to Env and Gag proteins are observed on the WB and especially in at-risk populations, HTLV infection should be suspected; such individuals should be followed-up and retested.

HLA class 1 alleles HLA-A*24,*26 and HLA-B*07,*61 were associated to susceptibility for HTLV-1 infection.While HLA-A*02 was associated to protection to HAM/TSP, HLA-B*07 was associated to susceptibility for disease. Alleles HLA-A*02 and HLA-B*27,*40,*48 were described in aboriginal populations of Russia genetically related to Andean aborigines. This study analyzed the association of HLA with susceptibility to HTLV-1 or -2 infections.

HTLV-1 is classified in seven subtypes (a-g) most of them restricted to specific regions (b-e), while the Cosmopolitan subtype (a) is worldwide distributed. Cosmopolitan subtype has experimented a degree of molecular diversity giving rise to five subgroups: Transcontinental (A), Japanese (B), West African (C), North African (D) and Black Peruvian (E).

Although the detection of HTLV antibodies became mandatory in Argentinean blood banks since 2005, there is no recommendation on how to perform the screening. As a consequence, there is a variable number of HTLV false positives depending on the kit used. The aim of the present study was to evaluate the performance of six commercial screening tests available currently for the initial diagnosis of HTLV-1/2 infection in South America. The positive panel included 14 HTLV-1 and 13 HTLV-2 samples confirmed by WB (HTLV-1/2 MP Diagnostics). The negative panel included 233 samples analysed with Architect (n=47), Diapro (n=46), MP (n=45), Murex (n=47) and Serodia (n=48), collected in 5 different institutions in a period of one up to 10 consecutive days. All of them were confirmed by n-PCR. The sensitivity for all HTLV diagnostic kits was 100.0%. The most specific test was Serodia (PA) (99,1%; 2/233), followed by the ELISAs: Celquest (98.3%, 4/233), Murex (97.8%; 5/233), MP and Architect (97.4%; 6/233), and Diapro (93,1%; 16/233). According to this data, 2 to 16 blood units out of 233 should have been discarded due to false positive results in a period of 10 days. This data must be considered when choosing the assays, not only to obtain an optimal efficiency on HTLV-1/2 diagnosis, to increase the number of potential blood units and to decrease the circulation of anxious individuals without a final result, but also to lower the overall cost-benefits of the diagnosis in the health care system.