Hi there Amy.
I dont see the connection with the pus cells on the swab & the thrush
unless someone is suggesting a secondary bacterial infection or admixed fungal & bacterial infection!
If you have been sexually active & practicing unprotected sex, it is very likely an STD
. Not all STD's are the major virus or bacteria ailments. Even thrush can be sexually transmitted !
If you have had protected sex with your most recent partner, then it is highly unlikely that he will have been infected; whether you have to tell him or not is entirely your call depending on your relationship status et al.
The treatment is very simple & i suggest you get seen by a dermatologist
nearest you at the earliest. There are simple combination kits that work in 24-48 hrs & all will be well.
Good luck & do continue to practice safe sex! Cheers!
Dr Praveen Rodrigues MD