Here is a short article about one of the COVID vaccines. It really shows how science works, as opposed to the ways right wing uneducated people imagine it.
--Kim
Scientists pieced together a mystery that's been puzzling researchers since 2021 — and the story is both fascinating and reassuring. When COVID-19 vaccines from AstraZeneca and J&J rolled out in 2021, a small number of people developed something alarming: dangerous blood clots combined with low platelets and bleeding. It was rare (about 1 in 200,000 vaccinated people) but serious.
Both vaccines used an adenovirus (a modified common cold virus) as a delivery vehicle. Interestingly, researchers found that natural adenovirus infections (no vaccine involved) can rarely cause a similar syndrome. That tells us this isn't a story about dangerous vaccine ingredients. It's a story about adenoviruses.
So what actually happened? The adenovirus carries a protein that resembles a human protein involved in clotting. When the immune system encounters it, it does exactly what it's supposed to — it makes antibodies to fight it. Up to 60% of people have a common inherited variation in how those antibodies are shaped, making them susceptible to confusing the two proteins. But for almost all of them, nothing goes wrong. A second thing also has to happen: a very specific mutation must occur within that same antibody-producing B cell that alters the binding properties of the antibody, resulting in 'redirection' to the body's own clotting factor instead of the virus protein (a case of mistaken identity). Both things must happen in the same B cell in the same person, which is why this was so rare, and why it was never seen with mRNA vaccines, which use completely different technology with no adenovirus involved.
The safety system worked. Cases were flagged within weeks. Regulators acted fast — restricting or pulling these specific vaccines while mRNA options stayed widely available. Then scientists spent years doing painstaking work to understand exactly what happened. (No cover-up, no failure; surveillance doing its job.)
And because we now know which adenovirus protein causes the confusion, future adenovirus-based vaccines — in development for Ebola, malaria, influenza, and more — can be designed without it. This complication doesn't have to happen to anyone, ever again.
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