>>11356680 (PB Notable) RE: 11 year olds' consent to vaccination

The WHO has a similar idea - parents actively opt out. Otherwise it's implied consent.

"This practice is based on the opt-out principle and parents who do not consent to vaccination are expected implicitly to take steps to ensure that their child or adolescent does not participate in the vaccination session. This may include not letting the child or adolescent attend school on a vaccination day, if vaccine delivery occurs through schools."

https://www.who.int/immunization/programmes_systems/policies_strategies/consent_note_en.pdf