It has never been more important for us to talk about the definition of veganism in the context of medications, including vaccines. The definition of veganism recognises that it is not always possible or practicable for vegans to avoid participating in animal use, which is particularly relevant to medical situations. In the case of Covid-19, vaccination is playing a fundamental role in tackling the pandemic and saving lives. As there is currently a legal requirement that all vaccines are tested on animals, at this point in time it is impossible to have a vaccine that has been created without animal use.
The “as far as is practicable and possible” caveat in The Vegan Society’s definition of veganism is a scary thing for carnists to contend with (if they’re even aware of it at all) because it removes any potential justification for them to not be vegan. So it’s easier for them to just call vegans anti-vax so they can continue feeling safe in their carnism.
And for any carnists that are eager to read that in bad-faith:
Vaccines are good. Animal exploitation is bad. It is possible to produce vaccines that don’t rely on animal exploitation. Therefore, most vegans advocate for producing vaccines that are not made by exploiting animals, but since it’s not practicable and possible for most people to get vaccines that aren’t produced with animal exploitation, we work with what we have and get vaccinated anyway until better vaccines are available.