[Ellie May]

Originally Posted by Kris Christine

The second vaccine selected is the one currently administered to a very high percentage of dogs. Both vaccines demonstrated excellent protection based on antibody testing for each of the first three study years. However, fewer than 30% of dogs in the first vaccine group, now five years since vaccination, had serum rabies antibody titer levels considered positive on the Rapid Fluorescent Focus Inhibition Test (RFFIT). (Note: RFFIT is the rabies titer standard established by the Centers for Disease Control within the USA [0.1 IU/mL] and the World Health Organization [0.5 IU/mL] for export to other rabies-free locations to be adequate to protect humans, not dogs, against rabies. There is no established standard for dogs, which means that the human standards must be extrapolated when assessing protection for other species.) Some of the dogs with low or no detected RFFIT antibody were further tested to determine if they had “immunologic memory”. This in vitro test shows whether memory is present or not, even in cases when serum antibody cannot be detected at a level considered to be protective. The results of this further testing indicated that most of the dogs vaccinated five years ago, even without a positive RFFIT, do have “immunologic memory”. As soon as a USDA licensed facility can be reserved, we plan to challenge some of those dogs with rabies virus to determine if the memory response demonstrated actually correlates with protection. ]

Originally Posted by Kris Christine

We are not done with the studies. The immunologic memory response findings were very high in the dogs tested with no or low RFFIT results. Those memory responses are a strong indication of protection, and based on that data, Dr. Dodds, Dr. Schultz and I expect the challenge to verify the results.

This is what confuses me. "Most" (not all) dogs had high cellular immunity. "Most" is shaky ground when I think of rabies.
It will be interesting to see what the challenge study shows.