If you don't want to offend you could try saying that while on a routine vets visit you discovered your dog has worms and your vet recommended that any dog your dog has been in contact with should be checked out. Almost hint that perhaps you didn't realise that your dog had worms and that she also might not be able to tell with her dog, but stress how bad worms are at the same time.
This way your not placing "blame" on anyone, and can look like a concerned friend rather than an accusing one.
If she starts getting smug or rude, you can always "clarify" exactly where you think she got the worms from.
Then next time she wants to come over / have a puppy play date you can simply ask if she managed to check out her pup yet and if not, then you can just say you don't want to risk re infecting your dog so you can't meet her quite yet, but for her to let you know when she's had her dog checked out. |