Not all flu vaccines are made from attenuated viruses though. There are recombinant vaccines for flu like Flublok, which is generated in bioreactors. You're right that mRNA vaccines have been mainly tested for cancer though. They don't integrate themselves into the host genome however, so they don't actually modify your DNA.
Not all flu vaccines are made from attenuated viruses though. There are recombinant vaccines for flu like Flublok, which is generated in bioreactors. You're right that mRNA vaccines have been mainly tested for cancer though. They don't integrate themselves into the host genome however, so they don't actually modify your DNA.