My daughter just had to have her 2-year-old (previously healthy 23-pound) cat put to sleep. He was fine until she took him in two weeks ago to have a physical. They gave him distemper and rabies shots. Two days later he became lethargic, refused to eat and was just generally not himself. He spent a week at the vets. She was told he was diabetic. She learned how to check his sugars and administer insulin. She had him home for two days and then had to bring him back to the vets with a fever, was told he had some soft of infection, two days in the vets, back home, back to the vets that night, now two days later (last night) she was told she had to make the decision on whether to put him down or not.

My question is whether anyone else has experienced something like this and what reactions can be attributed to the vaccines

I have been through a similar situation and I understand how you feel. Your cat is normal and healthy one day, then dead a few days later... It's heart-wrenching.

Like people, cats can have adverse reactions to common medications. Whether the vaccinations were a direct cause can probably only be determined through an autopsy.

In my case, I know the doctor and surgeon that tried to help my cat were doing the best they humanly could. They followed best practices, they did the best they could, but despite their efforts my cat died on the operating table.

Sometimes our loved ones are taken from us too soon.
Your cat, like mine, deserved more time to love and be loved in this world.