A prostitute sat on my back without dress, I was wearing full dress (T-shirt, vests and briefs and jeans pant), whether it would transmit aids due to her vaginal fluid in my dress?
Thank you for your inquiry. From what we gather from the question, you were asking about HIV transmission through clothing. From the information given, this scenario is determined to be no risk (transmission of HIV is not possible in the given scenario). For HIV transmission to occur, specific HIV+ fluids (e.g. semen, pre-cum, vaginal fluid, rectal fluid) must come into direct contact with the bloodstream of an HIV- person. Most of the body's surfaces are "dry" (e.g. legs, arms) and they don't allow HIV to enter the body. HIV also does not survive long outside the human body and cannot reproduce outside a human host. 
Recommendation: No need for HIV test with the scenario provided, refer to a physician for other health related questions
Regards, AIDS Vancouver Helpline/Online, Ashley
References: 1. CDC Centers for Disease Control and Prevention. HIV transmission [Internet]. https://www.cdc.gov/hiv/basics/transmission.html. 2018 [Cited September 12, 2018].