Scientists are working on vaccines that spread like a disease

We now have the technology to develop vaccines that spread themselves

A possible solution is to create vaccines that spread themselves through an animal population.

These “self-disseminating vaccines” can be developed in at least two ways. The conventional approach relies on applying a vaccine to the fur of captured animals and releasing them. When these animals return to their natural homes, social grooming results in the vaccine being ingested by other individuals, magnifying the level of immunity that can be achieved.

https://www.newscientist.com/article/mg24732960-100-we-now-have-the-technology-to-develop-vaccines-that-spread-themselves/

Scientists are working on vaccines that spread like a disease. What could possibly go wrong?

How they work. Self-spreading vaccines are essentially genetically engineered viruses designed to move through populations in the same way as infectious diseases, but rather than causing disease, they confer protection. Built on the chassis of a benign virus, the vaccines have genetic material from a pathogen added to them that stimulates the creation of antibodies or white blood cells in “infected” hosts.

These vaccines could be particularly useful, some scientists say, for wildlife populations where direct vaccination is difficult due to issues like inaccessible habitats, poor infrastructure, high costs, or lack of resources. The idea, essentially, is to vaccinate a small proportion of a population through direct inoculation. These so-called founders will then passively spread the vaccine to other animals they encounter either by touch, sex, nursing, or breathing the same air. Gradually, these interactions could build up population-level immunity.

https://thebulletin.org/2020/09/scientists-are-working-on-vaccines-that-spread-like-a-disease-what-could-possibly-go-wrong/

Project Coast: Apartheid's Chemical and Biological Warfare Programme

https://unidir.org/publication/project-coast-apartheids-chemical-and-biological-warfare-programme