The advice to give a ferret with lapsed or unknown vax a series of 2 shots to be safe could possibly do more damage than good. The reason for a series of shots is the maternal immunity and not knowing for each individual when it has waned. So you give a series to catch all the animals and so none will go unprotected. In essence if you waited till the animal was 16 to 20 weeks one shot could be given. Some will say you are "boosting" the vaccine but you really are not by that much, and the ones given when they still have the maternal immunities override the vacs anyways. Even the AVMA has acknowledged that giving boosters to an immunized animal has little or no effect and can be harmful. If you have an older ferret with unknown history one shot is all that is needed. I think in the effort to be overly cautious, people can actually be causing damage and stress to the animal, and if you add in that a ferret may have come from a bad situation and may not be in the greatest of health to start with (and vaccines are NOT supposed to be given to unhealthy animals), it is even more so. I have heard this from other vets, so some vets do advise this. At least something to consider. ~Amy~ [Posted in FML issue 4594]