Updated On September 23rd, 2025
Pet's info: Cat | Domestic Shorthair | Male | neutered | 4 months and 18 days old | 5 lbs
What age is it okay to mix a positive FeLV cat with a negative? I’m fostering 3 cats. The youngest is 4 months and he’s vaccinated, the FeLV positive one is 6 months, and the oldest is 1 1/2 years.
1 Answer
Published on December 20th, 2018
Good question. There is no particular age but a good idea would be to have them coexist when the youngest is fully vacicnated. I would wait at least 2 weeks after fully vaccinating the youngest one. If you really want to be cautious I would wait until they are all at least 8 months of age, because they are nearing adulthood and have a pretty sturdy immune system by then. Continue to have them tested for FeLV once a year to ensure everyone is still negative because the vaccine is not 100% protective, but still pretty effective. Thanks for visiting Petco Pet Education Center, formerly Petcoach and take care of your kitties! Take care.
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