Hello and welcome,
It is possible that it may have come from your cats though the species infecting cats and dogs are usually different from those causing human infection.
The commonest source is water borne and as vaginal infections are rare, it is not been mentioned as a sexually transmitted disease
. However since we do not know how vaginal giardiasis
behaves, it is better to get your partners semen as well as urine and penile swab tested for infection. If it is there he can get treated. Even empirical therapy may be provided to your partner as we do not know if it is possible for it to get sexually transmitted.
So please discuss this with your doctor and then decide.
Hope this was helpful.
Thanks for the query.
Feel free to ask more.
Dr Madhuri Bagde