Findings from a quiz taken by 5,000 people showed the public are "in the dark" about the realities of human immunodeficiency (HIV) virus, the National Aids Trust (NAT) said.
The survey findings, released on the 30th anniversary of the discovery of HIV, showed one in five, or 20%, of the public wrongly believe people with HIV can only expect to live for 10 years after acquiring the virus, even if they are on treatment and not diagnosed late.
Only 16% of respondents correctly stated people with HIV can expect to have a normal life expectancy where they are being successfully treated and they are not diagnosed late.
The research also showed more than a third, or 36%, of people wrongly thought being HIV positive prevented someone from working as a nursery school teacher, a chef or with people with mental health problems.
The charity said the only job someone HIV positive cannot do is work in the front-line armed forces, a ban applying to anyone with a long-term medical condition which requires daily medication.
Dentists, surgeons and midwives who are HIV positive can practise as long as they are monitored and their "viral load" - the level of the HIV virus in their blood - remains undetectable, the charity said.
The charity said an estimated 100,000 people are HIV positive in the UK, of whom around 22,000 are thought to be undiagnosed.