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Humans cannot be infected with the feline leukemia virus. We cannot be affected by it in any way, regardless of any type of exposure.
I have never heard of a cat that is "slightly infected" with leukemia. They are either positive or negative for the virus. If your vet has only performed the in hospital snap test, they can follow up with a test called an IFA. If this is also positive, it is likely your cat will develop a leukemia related disease in the near future. If the IFA is negative, there is a better chance that she will remain symptom free.
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