RESUMO
El Poder Legislativo chileno propone una ley que elimine el timerosal como preservante de las vacunas parenterales del Programa Nacional de Inmunizaciones, proyecto que el Poder Ejecutivo se ha propuesto vetar. El mundo científico informa mayoritariamente que la sospecha de neurotoxicidad atribuida al timerosal es infundada. Pese a ello, las autoridades médicas han oscilado entre sostener que la precaución sugiere apoyar la ley y en otros momentos han manifestando que es más precautorio mantener los programas de vacunación actualmente vigentes. Estas contradicciones y oposiciones ilustran que materias que conciernen a la ciudadanía, requieren una reflexión bioética acabada sobre las políticas públicas sanitarias. Han quedado claro las deficiencias de la deliberación política y la falta de participación social en decisiones que, dado el grado de incertidumbre involucrada en temas como inmunización, requieren no sólo la inclusión de la ciudadanía sino el respeto de la autonomía individual para aceptar o rechazar la inclusión en los programas de vacunación propuestos por las políticas sanitarias. La participación ciudadana en nuestro país se ve severamente limitada por la falta de instrumentos sociales como el plebiscito, el ombudsman y, especialmente, la desidia en crear la Comisión Nacional de Bioética exigida por la Ley 20.120 de 2006, una de cuyas funciones más importantes es mediar deliberativamente entre legos, expertos y políticos en la generación de políticas sanitarias legitimadas por la participación ciudadana.
Chilean legislators have voted to ban vaccines preserved with thiomersal, an initiative that the Executive has vetoed. Most scientific evidence has dismissed the alleged toxicity of this substance, in accordance with the formal and publicly expressed opinion of local experts, and yet, medical authorities have issued contradictory statements. Some have argued that the principle of precaution suggests eliminating thiomersal preserved vaccines; others have declared that current vaccines should be maintained to protect the population. From the perspective of bioethics, this polemic is another example of the shortcoming of the deliberation process leading to controversial laws in lieu of including citizens in the discussion of regulations that harbor uncertainties, and respect for individual autonomy to accept or reject public immunization programs. The Chilean legal system has been unwilling to implement participatory democratic procedures like plebiscites or institutions such as the ombudsman. In 2006 a law was enacted that creates a National Commission of Bioethics, but successive governments have failed to create such a commission, which is an efficient social instrument to conduct deliberation on bioethical issues that require a balanced participation of the public, experts, and politicians.
Assuntos
Humanos , Bioética , Conservantes Farmacêuticos , Timerosal , Vacinação em Massa/ética , Vacinação em Massa/legislação & jurisprudência , Chile , Medicina Baseada em Evidências , Saúde Pública , Política Pública , Programas de Imunização/legislação & jurisprudência , Participação SocialRESUMO
Since introduction of the pertussis vaccine in 1940’s the morbidity and mortality due to the infection has been markedly reduced all over the world. However the adverse effects of the inactivated whole cell pertussis vaccine like pain, swelling at the site of injection, fever, vomiting anorexia, persistent crying & drowsiness have been the cause of great concern, till date. Also the safety concerns over the use of thiomersal as an inactivating agent as well preservative have been raised in the recent past. Studies in many countries have been initiated to reduce or replace thiomersal & using other inactivating agents in the vaccines. Limited studies have been conducted in India. The present study has been undertaken as an attempt to reduce the quantity of thiomersal and modification in the procedure of production of the pertussis vaccine to reduce the toxicity, to produce better quality of whole cell pertussis vaccine. To achieve this, at the time of production of the whole cell pertussis vaccine, at Kasauli, as per the standard procedure recommended by WHO, three parallel batches of the pertussis culture were inactivated in fermenter before harvesting and thiomersal was used only one time for suspending the bacterial mass after harvesting. The resultant modified vaccine so prepared when tested showed that it was of better quality as compared to the one produced by standard procedure, when tested in mice.
RESUMO
El timerosal es un derivado del mercurio utilizado desde 1930 como preservante de vacunas. En las últimas décadas ha sido cuestionada su seguridad, especialmente por la posibilidad de toxicidad neurológica. La revisión de varios estudios realizados en niños que recibieron vacunas que contienen timerosal y la posición de organismos de expertos internacionales en relación al uso de este compuesto en vacunas, permite al Comité Consultivo de Inmunizaciones concluir que no existe evidencia de eventos adversos en lactantes o niños por exposición al timerosal contenido en vacunas rutinarias y, por lo tanto, no habría razón para modificar las actuales prácticas de inmunización en Chile.
Thimerosal is a mercury derivative included in vaccines since 1930 with the aim to prevent microbial contamination. During the last decades, the use of thimerosal has been questioned, specifically because of a potential association with neurotoxicity. After a thorough review of published studies on pediatric use of thimerosal-containing vaccines, and of position papers from international expert groups, the Consultive Committee of Immunizations of the Chilean Society of Infectious Diseases concludes that there is no solid evidence of adverse events associated with the use of thimerosal containing vaccines in infants and children. Therefore, a change in current vaccine practices refererred to thimerosal-containing vaccines is not justified in Chile.
Assuntos
Criança , Humanos , Lactente , Conservantes Farmacêuticos , Timerosal , Vacinas/química , Transtorno Autístico/induzido quimicamente , Chile , Conservantes Farmacêuticos/efeitos adversos , Padrões de Referência , Sociedades Médicas , Timerosal/efeitos adversos , Vacinas/efeitos adversosRESUMO
OBJECTIVE: To establish a method for the determination of the content of thiomersal in hepatitis B vaccine. METHODS: The content of thiomersal in hepatitis B vaccine was determined by flow injection-hydride generation atomic absorption spectrometry. The samples were treated by reflux digestion method with 4% sulphuric acid as medium,0.5% potassium borohydride as reducing agent,and 0.5% sulphuric acid as supporting liquid. RESULTS: The linear range of thiomersal was 5.0～100 ?g?L-1,with an average recovery rate of 100.6%(RSD=0.89%) and the lowest detection limit of 1.00 ?g?L-1. CONCLUSION: The method is simple,rapid and sensitive,and suitable for the determination of the content of thiomersal in hepatitis B vaccine.