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INTRODUCTION: Safety in Transfusion Medicine is subject to regulations and government legislation within a total quality framework. The aim of this study was to evaluate the impact of seroprevalence and indeterminate results on lost units and cost per donation. METHODS: A prospective cross-sectional study was performed in the Blood Bank and Transfusion Therapy Department of the Hospital Central de la Policia Nacional del Perú in Lima, Peru. All completed donations (replacement/voluntary) without complications were included in this study. Every donation met the institutional requirements and quality criteria of Programa Nacional de Hemoterapia y Bancos de Sangre (PRONAHEBAS). Data analysis was achieved using the Statistical Package for the Social Sciences. RESULTS: A total of 7723 donations were evaluated during 2014 and 2015 with 493 being seropositive (overall prevalence 5.25%) and 502 having indeterminate results (overall prevalence 5.35%). Thus total loss was 995units, 437.8L of blood and 49,750 US dollars. The most common seropositive infectious markers were the core antibody of hepatitis B virus (2.82%) and syphilis (1.02%), and the most common indeterminate results were Chagas disease (1.27%) and the core antibody of hepatitis B virus (1.26%). There was no significant change in the prevalence of seropositivity (p-value=0.243) or indeterminate results (p-value=0.227) over the two-year period of the study. A statistical correlation was found between the cost per lost donation and the most prevalent markers (rho=0.848; p-value=<0.001). CONCLUSION: Seroprevalence was lower than the regional mean, but the prevalence of indeterminate results was elevated causing a great impact on blood supply and economic losses to this institution.

RESUMO

ABSTRACT Introduction: Safety in Transfusion Medicine is subject to regulations and government legislation within a total quality framework. The aim of this study was to evaluate the impact of seroprevalence and indeterminate results on lost units and cost per donation. Methods: A prospective cross-sectional study was performed in the Blood Bank and Transfusion Therapy Department of the Hospital Central de la Policia Nacional del Perú in Lima, Peru. All completed donations (replacement/voluntary) without complications were included in this study. Every donation met the institutional requirements and quality criteria of Programa Nacional de Hemoterapia y Bancos de Sangre (PRONAHEBAS). Data analysis was achieved using the Statistical Package for the Social Sciences. Results: A total of 7723 donations were evaluated during 2014 and 2015 with 493 being seropositive (overall prevalence 5.25%) and 502 having indeterminate results (overall prevalence 5.35%). Thus total loss was 995 units, 437.8 L of blood and 49,750 US dollars. The most common seropositive infectious markers were the core antibody of hepatitis B virus (2.82%) and syphilis (1.02%), and the most common indeterminate results were Chagas disease (1.27%) and the core antibody of hepatitis B virus (1.26%). There was no significant change in the prevalence of seropositivity (p-value = 0.243) or indeterminate results (p-value = 0.227) over the two-year period of the study. A statistical correlation was found between the cost per lost donation and the most prevalent markers (rho = 0.848; p-value = <0.001). Conclusion: Seroprevalence was lower than the regional mean, but the prevalence of indeterminate results was elevated causing a great impact on blood supply and economic losses to this institution.

Assuntos

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BACKGROUND: Transfusion-transmitted infections are a major problem associated with blood transfusion. The aim of this study was to determine prevalence and trends of HBV, HCV and HIV in blood donors in Argentina. METHODS: A retrospective study was carried out in blood donors of 27 transfusion centers covering the whole country over a period of eight years (2004-2011). Serologic screening assays for HBsAg, anti-HBc, anti-HCV, and anti-HIV were performed in all centers and nucleic acid amplification testing (NAT) was performed in 2 out of the 27 centers. RESULTS: The 2,595,852 samples tested nationwide from 2004 to 2011 showed that the prevalence of HBsAg decreased from 0.336% to 0.198% (p < 0.0001), that of anti-HBc from 2.391% to 2.007% (p < 0.0001), that of anti-HCV from 0.721% to 0.460%, (p < 0.0001) and that of anti-HIV from 0.208% to 0.200 (p = 0.075). The prevalence of HBV, HCV and HIV was unevenly distributed among the different regions of the country. Two out of 74,838 screening- negative samples were positive in NAT assays (1 HIV-RNA and 1 HCV-RNA); moreover, HBV-DNA, HCV-RNA and HIV-RNA were detected in 60.29, 24.54 and 66.67% of screening-positive samples of the corresponding assays. As regards donors age, positive HBV-DNA and HCV-RNA donors were significantly older than healthy donors (46.6, 50.5 and 39.5 y respectively, p < 0.001). CONCLUSIONS: Argentina has a low prevalence of HBsAg, anti-HCV and anti-HIV in blood donors, with a decreasing trend for HBsAg, anti-HBc and anti-HCV but not for anti-HIV over the last 8 years. The uneven distribution of transfusion-transmitted infections prevalence among the different regions of the country highlights the need to implement regional awareness campaigns and prevention. The discrepancy between samples testing positive for screening assays and negative for NAT assays highlights the problem of blood donors who test repeatedly reactive in screening assays but are not confirmed as positive upon further testing. The uneven distribution of age between healthy donors and NAT-positive donors could be related to changes in risks of these pathogens in the general population and might be attributed to a longer exposure to transmission risk factors in elderly people.

Assuntos

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Las infecciones emergentes juegan un papel importantísimo en medicina transfusional. La experiencia con HIV puso en evidencia la necesidad de actuar rápidamente. La lentitud en la respuesta de los Bancos de Sangre y la falta de un liderazgo en la adopción de medidas preventivas dieron lugar a una transmisión importante por vía transfusional. En cuanto a las hepatitis postransfusionales NANB, aprendimos las lecciones acerca de las pruebas subrogantes. Sin embargo, la respuesta para prevenir la transmisión de HCV fue lenta porque la comunidad científica estaba focalizada en la transmisión de HIV. En el caso del XMRV, la presión ejercida por la comunidad fue muy importante. Se formaron grupos multidisciplinarios de expertos que realizaron gran cantidad de estudios y la respuesta ocurrió rápidamente, aunque al poco tiempo se demostró que este patógeno no era relevante para la Medicina Transfusional. Con respecto al WNV, la familiaridad con los modelos desarrollados por el CDC para estimar los riesgos y las lecciones aprendidas por las experiencias con HIV y HCV facilitaron una respuesta rápida y se implementaron medidas rápidamente para minimizar el riesgo de transmisión por vía transfusional. Se abrió un nuevo paradigma: la importancia de considerar los riesgos de transfusión que pueden derivar de agentes que causan viremias breves, usualmente asintomáticas, pero con el potencial de generar brotes estacionales de alta incidencia. La respuesta a la amenaza con WNV fue rápida, apropiada y exitosa. Las nuevas herramientas de biología molecular han permitido el aislamiento de numerosos gérmenes emergentes y lo seguirán haciendo en el futuro. Estar alertas ante nuevos patógenos de potencial importancia es nuestra responsabilidad.

Emerging infections play an extremely important role in transfusion medicine. Experience with HIV highlighted the necessity to act quickly. The slow Blood Banks response and the lack of leadership in the adoption of preventive measures resulted in a significant transfusional transmission. Regarding the post-transfusion NANB hepatitis, we have learned the lessons about the surrogate tests. However, the response to prevent HCV transmission was slow given that the scientific community was focused on HIV transmission. In the case of XMRV, pressure from the community was extremely important. Multidisciplinary groups of experts who conducted many studies were formed and the answer came quickly, but soon it was proved that this pathogen was not relevant to Transfusion Medicine. With respect to WNV, familiarity with the models developed by the CDC to estimate the risks and lessons learned from experiences with HIV and HCV facilitated a quick response, and measures were quickly implemented to minimize the risk of transmission by transfusion. A new paradigm came up: the importance of con­sidering the risks of transfusion that may result from agents that cause brief, usually asymptomatic viremia, but with the potential to generate high incidence seasonal outbreaks of viralloads. The response to the threat with WNV was rapid, appropriate and successful. The new tools of molecular biology have allowed the isolation of many emerging germs and will continue to do so in the future. Being alert to new pathogens of potential importance is our responsibility.

Assuntos

RESUMO

Las infecciones emergentes juegan un papel importantísimo en medicina transfusional. La experiencia con HIV puso en evidencia la necesidad de actuar rápidamente. La lentitud en la respuesta de los Bancos de Sangre y la falta de un liderazgo en la adopción de medidas preventivas dieron lugar a una transmisión importante por vía transfusional. En cuanto a las hepatitis postransfusionales NANB, aprendimos las lecciones acerca de las pruebas subrogantes. Sin embargo, la respuesta para prevenir la transmisión de HCV fue lenta porque la comunidad científica estaba focalizada en la transmisión de HIV. En el caso del XMRV, la presión ejercida por la comunidad fue muy importante. Se formaron grupos multidisciplinarios de expertos que realizaron gran cantidad de estudios y la respuesta ocurrió rápidamente, aunque al poco tiempo se demostró que este patógeno no era relevante para la Medicina Transfusional. Con respecto al WNV, la familiaridad con los modelos desarrollados por el CDC para estimar los riesgos y las lecciones aprendidas por las experiencias con HIV y HCV facilitaron una respuesta rápida y se implementaron medidas rápidamente para minimizar el riesgo de transmisión por vía transfusional. Se abrió un nuevo paradigma: la importancia de considerar los riesgos de transfusión que pueden derivar de agentes que causan viremias breves, usualmente asintomáticas, pero con el potencial de generar brotes estacionales de alta incidencia. La respuesta a la amenaza con WNV fue rápida, apropiada y exitosa. Las nuevas herramientas de biología molecular han permitido el aislamiento de numerosos gérmenes emergentes y lo seguirán haciendo en el futuro. Estar alertas ante nuevos patógenos de potencial importancia es nuestra responsabilidad. (AU)

Emerging infections play an extremely important role in transfusion medicine. Experience with HIV highlighted the necessity to act quickly. The slow Blood Banks response and the lack of leadership in the adoption of preventive measures resulted in a significant transfusional transmission. Regarding the post-transfusion NANB hepatitis, we have learned the lessons about the surrogate tests. However, the response to prevent HCV transmission was slow given that the scientific community was focused on HIV transmission. In the case of XMRV, pressure from the community was extremely important. Multidisciplinary groups of experts who conducted many studies were formed and the answer came quickly, but soon it was proved that this pathogen was not relevant to Transfusion Medicine. With respect to WNV, familiarity with the models developed by the CDC to estimate the risks and lessons learned from experiences with HIV and HCV facilitated a quick response, and measures were quickly implemented to minimize the risk of transmission by transfusion. A new paradigm came up: the importance of con¡sidering the risks of transfusion that may result from agents that cause brief, usually asymptomatic viremia, but with the potential to generate high incidence seasonal outbreaks of viralloads. The response to the threat with WNV was rapid, appropriate and successful. The new tools of molecular biology have allowed the isolation of many emerging germs and will continue to do so in the future. Being alert to new pathogens of potential importance is our responsibility. (AU)

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West Nile virus is a member of the Flaviviridae family. It was first isolated in Uganda and is indigenous to Africa, Asia, Australia and southern Europe. In recent years, local epidemics have been reported in Romania, Russia and Israel. In 1999 the virus presented a rapid emergence in North America and until November 2002 it has caused over 4,100 symptomatic infections in humans, of whom more than 240 have died. The life cycle of the virus includes mosquitoes as vectors with birds as amplifying viremic vertebrate hosts. Human, horses and other animals serve as dead-end hosts. Most infections are mild, with symptoms primarily being fever, headache, and myalgias. People older than 50 years are at highest risk of severe disease, which include encephalomyelitis. In 2002, 5 new modes of transmission were recognized: blood transfusion, organ transplantation, breast-feeding, transplacental transmission and occupational exposure in laboratory workers. Regarding blood transfusion, during the 2002 West Nile virus epidemic in the United States, 23 patients were confirmed to have acquired West Nile virus through transfused red cells, platelets or fresh-frozen plasma. Currently, there is no specific drug treatment or vaccine against the infection, and avoiding mosquito bites is the best way to protect against the disease.

Assuntos

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West Nile virus is a member of the Flaviviridae family. It was first isolated in Uganda and is indigenous to Africa, Asia, Australia and southern Europe. In recent years, local epidemics have been reported in Romania, Russia and Israel. In 1999 the virus presented a rapid emergence in North America and until November 2002 it has caused over 4,100 symptomatic infections in humans, of whom more than 240 have died. The life cycle of the virus includes mosquitoes as vectors with birds as amplifying viremic vertebrate hosts. Human, horses and other animals serve as dead-end hosts. Most infections are mild, with symptoms primarily being fever, headache, and myalgias. People older than 50 years are at highest risk of severe disease, which include encephalomyelitis. In 2002, 5 new modes of transmission were recognized: blood transfusion, organ transplantation, breast-feeding, transplacental transmission and occupational exposure in laboratory workers. Regarding blood transfusion, during the 2002 West Nile virus epidemic in the United States, 23 patients were confirmed to have acquired West Nile virus through transfused red cells, platelets or fresh-frozen plasma. Currently, there is no specific drug treatment or vaccine against the infection, and avoiding mosquito bites is the best way to protect against the disease. (AU)

Assuntos

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Although each donated unit of blood is tested for evidence of infection by specific agents, there are at least four potential reasons why transmission of these agents may still occur: a) the donor has negative laboratory test results during the early stages of infection, known as the window period, b) the existence of a chronic carrier state in which a clinically asymptomatic donor will persistently test negative on a screening assay, c) donors harbouring a mutant or atypical variant and d) laboratory errors when performing the screening tests. Measures to assure the safety of blood and blood components include use of voluntary donors, donor selection and questioning, laboratory testing for serological markers of infections, maintenance of registries of disqualified donors and, more recently, the introduction of direct testing for viral nucleic acids. All these measures must be accompanied by rigorous quality control systems. The potential risk of transfusion-transmitted infectious diseases can be estimated by reviewing the records of blood donations, the screening procedures and determining the prevalence of the serologic markers of infectious diseases. Accurate estimates of the risk of transfusion-transmitted infections are needed in order to monitor the safety of the blood supply and evaluate the yield and cost effectiveness of alternatives to allogeneic transfusion. Genomic screening for infectious agents, especially viruses, became possible with the development of various nucleic acid amplification techniques. They combine the advantages of direct detection of the organism with a sensitivity several orders of magnitude higher than that of traditional methods.

Assuntos

RESUMO

Although each donated unit of blood is tested for evidence of infection by specific agents, there are at least four potential reasons why transmission of these agents may still occur: a) the donor has negative laboratory test results during the early stages of infection, known as the window period, b) the existence of a chronic carrier state in which a clinically asymptomatic donor will persistently test negative on a screening assay, c) donors harbouring a mutant or atypical variant and d) laboratory errors when performing the screening tests. Measures to assure the safety of blood and blood components include use of voluntary donors, donor selection and questioning, laboratory testing for serological markers of infections, maintenance of registries of disqualified donors and, more recently, the introduction of direct testing for viral nucleic acids. All these measures must be accompanied by rigorous quality control systems. The potential risk of transfusion-transmitted infectious diseases can be estimated by reviewing the records of blood donations, the screening procedures and determining the prevalence of the serologic markers of infectious diseases. Accurate estimates of the risk of transfusion-transmitted infections are needed in order to monitor the safety of the blood supply and evaluate the yield and cost effectiveness of alternatives to allogeneic transfusion. Genomic screening for infectious agents, especially viruses, became possible with the development of various nucleic acid amplification techniques. They combine the advantages of direct detection of the organism with a sensitivity several orders of magnitude higher than that of traditional methods (AU)#S

Assuntos

RESUMO

Although each donated unit of blood is tested for evidence of infection by specific agents, there are at least four potential reasons why transmission of these agents may still occur: a) the donor has negative laboratory test results during the early stages of infection, known as the window period, b) the existence of a chronic carrier state in which a clinically asymptomatic donor will persistently test negative on a screening assay, c) donors harbouring a mutant or atypical variant and d) laboratory errors when performing the screening tests. Measures to assure the safety of blood and blood components include use of voluntary donors, donor selection and questioning, laboratory testing for serological markers of infections, maintenance of registries of disqualified donors and, more recently, the introduction of direct testing for viral nucleic acids. All these measures must be accompanied by rigorous quality control systems. The potential risk of transfusion-transmitted infectious diseases can be estimated by reviewing the records of blood donations, the screening procedures and determining the prevalence of the serologic markers of infectious diseases. Accurate estimates of the risk of transfusion-transmitted infections are needed in order to monitor the safety of the blood supply and evaluate the yield and cost effectiveness of alternatives to allogeneic transfusion. Genomic screening for infectious agents, especially viruses, became possible with the development of various nucleic acid amplification techniques. They combine the advantages of direct detection of the organism with a sensitivity several orders of magnitude higher than that of traditional methods.