AstraZeneca vaccine faces blood clot problems

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Germany, France, Italy and Spain have it all stop vaccinations with AstraZeneca’s COVID-19[feminine vacuna, després d’informacions de coàguls de sang rars en persones que van rebre els trets.

Aquests moviments dels quatre països més grans de la Unió Europea segueixen pauses en diversos països membres més petits i marquen una nova crisi de confiança per a un vacuna assequible això es veu com la millor esperança per accelerar la vacunació contra el COVID-19 a tot el món en desenvolupament.

Els experts subratllen que encara no hi ha proves clares que indiquin que la vacuna estigui causant aquests coàguls, i que els reguladors investiguen els casos. Però les darreres preocupacions segueixen abans preguntes dels científics sobre com la companyia ha comunicat problemes amb seguretat i eficàcia de la seva vacuna. També arriba poc abans que s’espera que AstraZeneca publiqui els resultats d’un assaig clínic a gran escala que determinarà si la FDA autoritza la vacuna als EUA.

Les pauses a la vacunació a Europa es van desencadenar en els informes de tres hospitalitzacions, inclòs un pacient que va morir, entre les persones que van rebre la vacuna a Noruega, i una nova mort a Dinamarca. En un declaració publicat l’11 de març, l’Agència Europea de Medicaments (el regulador que és l’equivalent de la UE a la FDA) va dir que hi havia hagut un total de 30 casos d ‘”esdeveniments tromboembòlics” o coàguls de sang, entre els 5 milions de persones que han rebut tirs d’AstraZeneca a la UE.

“Actualment no hi ha indicis que la vacunació hagi causat aquestes condicions, que no figuren com a efectes secundaris amb aquesta vacuna”, va dir l’EMA. “La posició del comitè de seguretat de l’EMA … és que els beneficis de la vacuna continuen superant els seus riscos i es pot continuar administrant la vacuna”.

AstraZeneca va dir que hi havia hagut un total de 37 casos reportats d’embòlia pulmonar i trombosi venosa profunda, ambdues afeccions causades per la coagulació de la sang, que és menys del que s’esperava de la taxa en la població general.

“Al voltant de 17 milions de persones a la UE i al Regne Unit han rebut la nostra vacuna, i el nombre de casos de coàguls de sang reportats en aquest grup és inferior als centenars de casos que s’esperava”, va dir Ann Taylor, director mèdic de la companyia. a declaració emès el 14 de març.

I l’Organització Mundial de la Salut ho és instant els països a seguir utilitzant la vacuna, fent ressò que no hi ha proves que provoquin coàguls de sang. Els experts de l’OMS es reuneixen per debatre els informes de coàguls de sang dimarts.

Tanmateix, un grapat d’incidents fan que alguns països es detinguin. Segons el ministre alemany de salut Jens Spahn, hi ha hagut set casos reportats d’una malaltia rara, trombosi sinusal venosa cerebral (CVST), dels 1,6 milions de persones que van rebre la vacuna AstraZeneca a Alemanya. L’Institut Paul Ehrlich, que forma part del ministeri de salut alemany, va dir dilluns que sí preocupat que es va informar de la malaltia juntament amb un sagnat inusual i un baix recompte de plaquetes sanguínies, que formen coàguls i eviten el sagnat.

El grapat de casos vistos a Alemanya fins ara seria més del que s’esperava, però podria ser un error estadístic. “[T]the likelihood that this single-result statistical pooling is actually quite high even when there is no cause and effect, ”said Paul Hunter, a public health specialist at the University of East Anglia, in a comment distributed via of the Science Media Center of the United Kingdom.

The EMA is meeting to discuss concerns about blood clotting on Tuesday and is expected to release its findings on Thursday. A prolonged gap in vaccination would be a worrying prospect, as COVID-19 cases are rising again in several EU nations, with Italy especially alarming wave – as more contagious variants spread.

Experts contacted by BuzzFeed News said that without knowing more about the patients ’cases, there was not enough evidence to draw clear conclusions about whether the vaccine caused clotting. “We would like to know the age of the cases, their previous medical history, and conditions that could predispose them to their risk of clot or bleeding,” said Orly Vardeny of the University of Minnesota, a pharmacist specializing in heart health.

“It may or may not be related to the vaccine. If it’s related to the vaccine and if it’s not seen everywhere, the most likely explanation would be a production problem, ”John Moore, a virologist at Weill Cornell Medical College in New York who works on the development, told BuzzFeed News (Some countries, including Austria, to own specifically cessation of vaccination of certain batches of the AstraZeneca vaccine.)

The new concerns are the latest developments in a series of stumbles against AstraZeneca’s COVID-19 vaccine, developed at Oxford University. In November, AstraZeneca sued Press release that your vaccine was 70% effective overall and could be up to 90% effective if given in half a dose during the first two shots. But many scientists they were skeptical, especially after the pharmaceutical company admitted that this regimen was the result of a poor dosing calculation. Later, AstraZeneca added to the confusion of changing their explanation for the 90% efficacy claimed from the dosage itself to the lag between the two doses.

A more serious case occurred in February, when trials in South Africa showed the vaccine it was not effective against the most contagious variant of the coronavirus circulating there. South Africa abruptly stopped plans to use the AstraZeneca vaccine and switched to vaccines manufactured by Johnson & Johnson and Pfizer / BioNTech.

Now scientists are waiting for the results of one great essay of the AstraZeneca vaccine made in the United States and other countries that will be the cornerstone of the company’s request to have the vaccine authorized for use by the FDA. But some experts are wondering if adding AstraZeneca to the vaccine armory used in the U.S. will create more problems, with anti-vaxxers likely to take advantage of negative publicity which surrounds it to undermine the broader impulse of vaccination.

“Do you really have a niche to fill? Would it be reliable enough? Or will it be another headache? Said Moore.

Children’s Health Defense, an organization that does peddled misinformation i conspiracy theories about vaccines for years, has already done so highlighted the news that several European countries are stopping their use of the vaccine.

Where the vaccine could make a big difference is in the developing world, especially in Africa, where vaccines are being launched. falling far behind. The Biden Administration is already under pressure to give already manufactured doses of the AstraZeneca vaccine to poorer nations, the The New York Times reported on March 11th. Meanwhile, COVAX, the partnership formed by WHO, the Coalition for Innovations in Epidemic Preparedness, and Gavi, the Vaccine Alliance, to provide affordable vaccines to the poorest countries, is based on the use of the AstraZeneca vaccine to administer hundreds of millions of doses worldwide in development.

“Safety is our primary concern: we know that national authorities and WHO are closely monitoring the situation and that the COVAX center will follow its guidance and recommendations,” a Gavi spokesman said in response to questions from BuzzFeed News . “No causal link has currently been established between the vaccine and thromboembolic events in individuals, and the vaccine remains an important and effective public health tool in the fight against this pandemic.”





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