Vaccine Associated Feline Sarcoma: Misty's Story

Despite the popular belief that all vaccines are both necessary and beneficial to your cat, there are sometimes hidden dangers that pet owners need to be aware of.

I'm a long time pet owner, and have experienced a lot with my cats over the years. Every cat I've ever had has been a rescue of a stray right off the street. Misty came to me as a 3 week old, 8-ounce baby, abandoned in a friend's yard, in October, 2004. We bottle fed and babied her, and she developed into a strong, seemingly healthy cat.

In the summer of 2005 - a particularly hot summer - Misty seemed to be sick. She was just lying around in the window all day, but so was her big sister, Jinx, so we weren't sure something was wrong. After a couple days, we decided to take her to the vet. Our suspicions were correct: Misty had a fever, and had we waited another day, she would have had to be admitted. After a cycle of antibiotics, she was back to normal.

Until the Fall, that is. Again she seemed not herself, and ended up with another round of antibiotics (one of these doses, either summer or fall, was an injection at the vet's). There had been a lot of activity in our house lately - replacing an old tile floor, using a strong new cleaning product (it made some of us sensitive humans sick, too!), and turning the furnace on for the first time of the season. We thought she might have allergies, so we'd keep an eye on her.

Misty's yearly physical and vaccines came President's weekend, 2006. She was a healthy 13 pounds, and was given her shots: 3-year rabies, 1 year distemper, 1 year feline leukemia. Within a couple weeks, we noticed a lump on Misty's leg. It was hard and solid, and she didn't like having it touched. It's not uncommon for cats to develop a temporary bump in response to a vaccine, but still we took her back to the vet. We were given some antibiotics, our vet made note of the lump's size, and we started watching it. We brought her back a few times for the vet to evaluate it; he was always very gracious and assured us it was getting smaller (at one point, 70% smaller than it was initially), but it's hard not to feel like you're overreacting.