Vaccine skeptics blocking transfusions for life-saving surgeries, Facebook groups fueling violence against doctors, and a global search for unvaccinated donors -- Covid-19 misinformation has produced a so-called "pure blood" movement.

The movement focuses on anti-vaccine narratives based on unfounded claims that getting blood from persons who have been immunized against the coronavirus "contaminates" the body.

Some have campaigned for blood banks that draw from "pure" unvaccinated people, and North American medics say they have received requests for transfusions from donors who have not gotten the vaccine.

Vaccine skeptics, dubbed "pure bloods," incite violence against doctors who provide coronavirus vaccines in closed social media forums, amid bogus claims of mass deaths of vaccinated people.

The recent high-profile instance of a New Zealand couple seeking to deny life-saving heart surgery for their infant on the grounds that any blood transfused could have originated from a vaccinated donor heightened the panic.

Their attitude forced a New Zealand court to temporarily take custody of the baby in order to facilitate the treatment, but the story became a cause celebre among vaccine skeptics worldwide.

According to the Safe Blood website, participants must pay an initial joining cost of 50 euros ($54), followed by a yearly fee of 20 euros.

In the United States, when more than 80% of the population has had at least one Covid shot, the Food and Drug Administration states that blood collectors are not required to screen for vaccination status.

Hospitals are also unable to advise patients about the status of donated blood.

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