I just took our cat in for a check up on her wound (healing nicely). And the vet talked to me about the flea treatment we are using for preventative reasons. Apparently "they" (forgot to ask who, I assume the big vet people) want us to stop using flea treatment in winter as fleas are becoming resistant to almost all treatments. She said if Stronghold plus stops working then "we are buggered". Is anyone else doing this? I am very reluctant to stop treatment as our cat goes outside a lot.