>> were made from deactivated viruses. I don't know how that process works exactly Check out the history of the Rabies vaccine, where the virus was weakened th

>> were made from deactivated viruses. I don't know how that process works exactly Check out the history of the Rabies vaccine, where the virus was weakened through aging: > derived from the spinal cord of an inoculated rabbit which had died of rabies 15 days earlier. https://en.wikipedia.org/wiki/Rabies_vaccine#History https://en.wikipedia.org/wiki/Rabies_vaccine#History > A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins. https://en.wikipedia.org/wiki/Inactivated_vaccine https://en.wikipedia.org/wiki/Inactivated_vaccine > The virus is killed using a method such as heat or formaldehyde. > Whole virus vaccines use the entire virus particle, fully destroyed using heat, chemicals, or radiation. > Split virus vaccines are produced by using a detergent to disrupt the virus. > Subunit vaccines are produced by purifying out the antigens that best stimulate the immune system to mount a response to the virus, while removing other components necessary for the virus to replicate or survive or that can cause adverse reactions