YouTube on Wednesday announced that it would be blocking anti-vaccine content.

The Washington Post also cited YouTube’s Vice President Of Global Trust and Safety Matt Halprin as saying that several prominent accounts would be blocked. These would include the Children's Health Defense, chaired by Robert F. Kennedy Jr., and Dr. Joseph Mercola.

The company wrote in a blog post that content "that falsely alleges that approved vaccines are dangerous and cause chronic health effects, claims that vaccines do not reduce transmission or contraction of disease, or contains misinformation on the substances contained in vaccines will be removed."

"This would include content that falsely says that approved vaccines cause autism, cancer or infertility, or that substances in vaccines can track those who receive them. Our policies not only cover specific routine immunizations like for measles or Hepatitis B, but also apply to general statements about vaccines."

YouTube asserted it had "consulted with local and international health organizations and experts in developing these policies. For example, our new guidance on vaccine side effects maps to public vaccine resources provided by health authorities and backed by medical consensus."

It added that there were "important exceptions to our new guidelines," noting, "we will continue to allow content about vaccine policies, new vaccine trials, and historical vaccine successes or failures on YouTube. Personal testimonials relating to vaccines will also be allowed, so long as the video doesn't violate other Community Guidelines, or the channel doesn't show a pattern of promoting vaccine hesitancy."