The campaign has already received widespread coverage from national press including The Independent and The Daily Mail - as well as attracting the likes of Downtown Abbey star Peter Egan.
Those wanting to participate are to share a photo of themselves onto social media with '#3in4' written on either their hand or on a paper note.
'Threat to humankind'
In a statement sent to Plant Based News, Viva! said: "Factory farms are breeding grounds for disease and a continuous threat to humankind.
"The next pandemic is just as likely to come from a pig farm as a wet market. We can reduce the risk of future pandemics, and end factory farming by going vegan."
Viva! is not the first to highlight the link between animal agriculture and infectious diseases. Last month, a BBC documentary warned intensive farming 'must change' to avoid future pandemics.
In the documentary, Veterinary Pathologist Professor Andrew Cunningham, who specializes in wildlife diseases, said: "It's not a coincidence that we talk bout avian influenza and swine influenza, those are the two species that are farmed intensively the most around the world.
"Thousands and thousands of animals packed in together and that's a very good environment for a new virus to emerge from a mutation."