Browsing by Author "Paredes, Roger (35410114800)"

The European HIV Drug Resistance Guidelines Panel, established to make recommendations to clinicians and virologists, felt that sufficient new information has become available to warrant an update of its recommendations, explained in both pocket guidelines and this full paper. The Panel makes the following recommendations concerning the indications for resistance testing: for HIV-1 (i) test earliest sample for protease and reverse transcriptase drug resistance in drug-naive patients with acute or chronic infection; (ii) test protease and reverse transcriptase drug resistance at virologic failure, and other drug targets (integrase and envelope) if such drugs were part of the failing regimen; (iii) consider testing for CCR5 tropism at virologic failure or when a change of therapy has to be made in absence of detectable viral load, and in the latter case test DNA or last detectable plasma RNA; (iv) consider testing earliest detectable plasma RNA when a successful nonnucleoside reverse transcriptase inhibitor-containing therapy was inappropriately interrupted; (v) genotype source patient when postexposure prophylaxis is considered; for HIV-2, (vi) consider resistance testing where treatment change is needed after treatment failure. The Panel recommends genotyping in most situations, using updated and clinically evaluated interpretation systems. It is mandatory that laboratories performing HIV resistance tests take part regularly in external quality assurance programs, and that they consider storing samples in situations where resistance testing cannot be performed as recommended. Similarly, it is necessary that HIV clinicians and virologists take part in continuous education and discuss problematic clinical cases. Indeed, resistance test results should be used in the context of all other clinically relevant information for predicting therapy response.

Background. Human immunodeficiency virus type 1 (HIV-1) subtype CRF01-AE originated in Africa and then passed to Thailand, where it established a major epidemic. Despite the global presence of CRF01-AE, little is known about its subsequent dispersal pattern. Methods. We assembled a global data set of 2736 CRF01-AE sequences by pooling sequences from public databases and patient-cohort studies. We estimated viral dispersal patterns, using statistical phylogeographic analysis run over bootstrap trees estimated by the maximum likelihood method. Results. We show that Thailand has been the source of viral dispersal to most areas worldwide, including 17 of 20 sampled countries in Europe. Japan, Singapore, Vietnam, and other Asian countries have played a secondary role in the viral dissemination. In contrast, China and Taiwan have mainly imported strains from neighboring Asian countries, North America, and Africa without any significant viral exportation. Discussion. The central role of Thailand in the global spread of CRF01-AE can be probably explained by the popularity of Thailand as a vacation destination characterized by sex tourism and by Thai emigration to the Western world. Our study highlights the unique case of CRF01-AE, the only globally distributed non-B clade whose global dispersal did not originate in Africa. © 2014 The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.

Background: Understanding HIV-1 subtype distribution and epidemiology can assist preventive measures and clinical decisions. Sequence variation may affect antiviral drug resistance development, disease progression, evolutionary rates and transmission routes.Results: We investigated the subtype distribution of HIV-1 in Europe and Israel in a representative sample of patients diagnosed between 2002 and 2005 and related it to the demographic data available. 2793 PRO-RT sequences were subtyped either with the REGA Subtyping tool or by a manual procedure that included phylogenetic tree and recombination analysis. The most prevalent subtypes/CRFs in our dataset were subtype B (66.1%), followed by sub-subtype A1 (6.9%), subtype C (6.8%) and CRF02_AG (4.7%). Substantial differences in the proportion of new diagnoses with distinct subtypes were found between European countries: the lowest proportion of subtype B was found in Israel (27.9%) and Portugal (39.2%), while the highest was observed in Poland (96.2%) and Slovenia (93.6%). Other subtypes were significantly more diagnosed in immigrant populations. Subtype B was significantly more diagnosed in men than in women and in MSM > IDUs > heterosexuals. Furthermore, the subtype distribution according to continent of origin of the patients suggests they acquired their infection there or in Europe from compatriots.Conclusions: The association of subtype with demographic parameters suggests highly compartmentalized epidemics, determined by social and behavioural characteristics of the patients. © 2013 Abecasis et al.; licensee BioMed Central Ltd.

Background: Understanding HIV-1 subtype distribution and epidemiology can assist preventive measures and clinical decisions. Sequence variation may affect antiviral drug resistance development, disease progression, evolutionary rates and transmission routes.Results: We investigated the subtype distribution of HIV-1 in Europe and Israel in a representative sample of patients diagnosed between 2002 and 2005 and related it to the demographic data available. 2793 PRO-RT sequences were subtyped either with the REGA Subtyping tool or by a manual procedure that included phylogenetic tree and recombination analysis. The most prevalent subtypes/CRFs in our dataset were subtype B (66.1%), followed by sub-subtype A1 (6.9%), subtype C (6.8%) and CRF02_AG (4.7%). Substantial differences in the proportion of new diagnoses with distinct subtypes were found between European countries: the lowest proportion of subtype B was found in Israel (27.9%) and Portugal (39.2%), while the highest was observed in Poland (96.2%) and Slovenia (93.6%). Other subtypes were significantly more diagnosed in immigrant populations. Subtype B was significantly more diagnosed in men than in women and in MSM > IDUs > heterosexuals. Furthermore, the subtype distribution according to continent of origin of the patients suggests they acquired their infection there or in Europe from compatriots.Conclusions: The association of subtype with demographic parameters suggests highly compartmentalized epidemics, determined by social and behavioural characteristics of the patients. © 2013 Abecasis et al.; licensee BioMed Central Ltd.

Technical advances in diagnostic techniques have permitted the possibility of multi-disease-based approaches for diagnosis and treatment monitoring of several infectious diseases, including tuberculosis (TB), human immunodeficiency virus (HIV), viral hepatitis and sexually transmitted infections (STI). However, in many countries, diagnosis and monitoring, as well as disease response programs, still operate as vertical systems, potentially causing delay in diagnosis and burden to patients and preventing the optimal use of available resources. With countries facing both human and financial resource constraints, during the COVID-19 pandemic even more than before, it is important that available resources are used as efficiently as possible, potential synergies are leveraged to maximise benefit for patients, continued provision of essential health services is ensured. For the infectious diseases, TB, HIV, hepatitis C (HCV) and STI, sharing devices and integrated services starting with rapid, quality-assured, and complete diagnostic services is beneficial for the continued development of adequate, efficient and effective treatment strategies. Here we explore the current and future potential (as well as some concerns), importance, implications and necessary implementation steps for the use of platforms for multi-disease testing for TB, HIV, HCV, STI and potentially other infectious diseases, including emerging pathogens, using the example of the COVID- 19 pandemic. © 2022 European Centre for Disease Prevention and Control (ECDC). All rights reserved.

Technical advances in diagnostic techniques have permitted the possibility of multi-disease-based approaches for diagnosis and treatment monitoring of several infectious diseases, including tuberculosis (TB), human immunodeficiency virus (HIV), viral hepatitis and sexually transmitted infections (STI). However, in many countries, diagnosis and monitoring, as well as disease response programs, still operate as vertical systems, potentially causing delay in diagnosis and burden to patients and preventing the optimal use of available resources. With countries facing both human and financial resource constraints, during the COVID-19 pandemic even more than before, it is important that available resources are used as efficiently as possible, potential synergies are leveraged to maximise benefit for patients, continued provision of essential health services is ensured. For the infectious diseases, TB, HIV, hepatitis C (HCV) and STI, sharing devices and integrated services starting with rapid, quality-assured, and complete diagnostic services is beneficial for the continued development of adequate, efficient and effective treatment strategies. Here we explore the current and future potential (as well as some concerns), importance, implications and necessary implementation steps for the use of platforms for multi-disease testing for TB, HIV, HCV, STI and potentially other infectious diseases, including emerging pathogens, using the example of the COVID- 19 pandemic. © 2022 European Centre for Disease Prevention and Control (ECDC). All rights reserved.

Background: International travel plays a role in the spread of HIV-1 across Europe. It is, however, not known whether international travel is more important for spread of the epidemic as compared to endogenous infections within single countries. In this study, phylogenetic associations among HIV of newly diagnosed patients were determined across Europe.Results: Data came from the SPREAD programme which collects samples of newly diagnosed patients that are representative for national HIV epidemics. 4260 pol sequences from 25 European countries and Israel collected in 2002-2007 were included.We identified 457 clusters including 1330 persons (31.2% of all patients). The cluster size ranged between 2 and 28. A number of 987 patients (74.2%) were part of a cluster that consisted only of patients originating from the same country. In addition, 135 patients (10.2%) were in a cluster including only individuals from neighboring countries. Finally, 208 patients (15.6%) clustered with individuals from countries without a common border. Clustering with patients from the same country was less prevalent in patients being infected with B subtype (P-value <0.0001), in men who have sex with men (P-value <0.0001), and in recently infected patients (P-value =0.045).Conclusions: Our findings indicate that the transmission of HIV-1 in Europe is predominantly occurring between patients from the same country. This could have implications for HIV-1 transmission prevention programmes. Because infections through travelling between countries is not frequently observed it is important to have good surveillance of the national HIV-1 epidemics. © 2013 Frentz et al.; licensee BioMed Central Ltd.

Background: International travel plays a role in the spread of HIV-1 across Europe. It is, however, not known whether international travel is more important for spread of the epidemic as compared to endogenous infections within single countries. In this study, phylogenetic associations among HIV of newly diagnosed patients were determined across Europe.Results: Data came from the SPREAD programme which collects samples of newly diagnosed patients that are representative for national HIV epidemics. 4260 pol sequences from 25 European countries and Israel collected in 2002-2007 were included.We identified 457 clusters including 1330 persons (31.2% of all patients). The cluster size ranged between 2 and 28. A number of 987 patients (74.2%) were part of a cluster that consisted only of patients originating from the same country. In addition, 135 patients (10.2%) were in a cluster including only individuals from neighboring countries. Finally, 208 patients (15.6%) clustered with individuals from countries without a common border. Clustering with patients from the same country was less prevalent in patients being infected with B subtype (P-value <0.0001), in men who have sex with men (P-value <0.0001), and in recently infected patients (P-value =0.045).Conclusions: Our findings indicate that the transmission of HIV-1 in Europe is predominantly occurring between patients from the same country. This could have implications for HIV-1 transmission prevention programmes. Because infections through travelling between countries is not frequently observed it is important to have good surveillance of the national HIV-1 epidemics. © 2013 Frentz et al.; licensee BioMed Central Ltd.

Human immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa through Haiti to United States. However, the pattern of the subsequent spread still remains poorly understood. Here we analyze a large dataset of globally representative HIV-1 subtype B strains to map their spread around the world over the last 50 years and describe significant spread patterns. We show that subtype B travelled from North America to Western Europe in different occasions, while Central/Eastern Europe remained isolated for the most part of the early epidemic. Looking with more detail in European countries we see that the United Kingdom, France and Switzerland exchanged viral isolates with non-European countries than with European ones. The observed pattern is likely to mirror geopolitical landmarks in the post-World War II era, namely the rise and the fall of the Iron Curtain and the European colonialism. In conclusion, HIV-1 spread through specific migration routes which are consistent with geopolitical factors that affected human activities during the last 50 years, such as migration, tourism and trade. Our findings support the argument that epidemic control policies should be global and incorporate political and socioeconomic factors. © 2016 The Authors

Human immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa through Haiti to United States. However, the pattern of the subsequent spread still remains poorly understood. Here we analyze a large dataset of globally representative HIV-1 subtype B strains to map their spread around the world over the last 50 years and describe significant spread patterns. We show that subtype B travelled from North America to Western Europe in different occasions, while Central/Eastern Europe remained isolated for the most part of the early epidemic. Looking with more detail in European countries we see that the United Kingdom, France and Switzerland exchanged viral isolates with non-European countries than with European ones. The observed pattern is likely to mirror geopolitical landmarks in the post-World War II era, namely the rise and the fall of the Iron Curtain and the European colonialism. In conclusion, HIV-1 spread through specific migration routes which are consistent with geopolitical factors that affected human activities during the last 50 years, such as migration, tourism and trade. Our findings support the argument that epidemic control policies should be global and incorporate political and socioeconomic factors. © 2016 The Authors

Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001. Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)-infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0. Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%-9.5%) in 2008-2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones. Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected. © The Author 2015.