Vaccination that does not prevent the spread of a virus will not eliminate the virus. It will however put strong selective pressure on the virus to mutate.
What was once a benign disease is now deadly, and requires a vaccine against mutation for the host to survive.
Marek’s disease was originally benign. By vaccinating chickens against it with a vaccine that did not prevent infection, it put strong selective pressure on the virus to mutate.
Now the virus is no longer benign, and if a chicken is not vaccinated, it WILL get the disease and die. Thus there is now an indefinite dependency on the vaccine to survive a virus made dangerous from prior generations of vaccination.
Vaccination that does not prevent the spread of a virus will not eliminate the virus. It will however put strong selective pressure on the virus to mutate.
What was once a benign disease is now deadly, and requires a vaccine against mutation for the host to survive.
Marek’s disease was originally benign. By vaccinating chickens against it with a vaccine that did not prevent infection, it put strong selective pressure on the virus to mutate.
Now the virus is no longer benign, and if a chicken is not vaccinated, it WILL get the disease and die. Thus there is now an indefinite dependency on the vaccine to survive a virus made dangerous from prior generations of vaccination.