The chaplain, Heather Leake-Date, is a Methodist minister and also a consultant pharmacist for HIV and sexual health at Brighton and Sussex University Hospitals NHS Trust.
She called for churches to use the day to raise awareness about the condition.
"When the HIV pandemic first came to prominence there was quite a lot of misunderstanding, a lot of prejudice, stigma and discrimination and some of that came from the Church or people of faith," she said in an interview with Premier.
She added: "There's a lot of negative stuff around people being deemed to have brought things upon themselves and it being a judgement, which is not true and is not the official line of the churches, but that message still persists."
Leake-Date said the main thing she would want people to know on World AIDS Day is that although those with the condition can have side effects from the medication, they mostly live normal lives.
She said: "We're in a very much more hopeful situation than we were 20 years ago.
"The important thing is for people to be tested and to be diagnosed, then they can be treated.
"People can live a pretty much normal life."
Listen to Heather Leake-Date speaking with Premier's Tola Mbakwe here:
