Three quarters of African respondents to a survey conducted on behalf of the BBC said HIV/Aids is one of their greatest concerns.
However, asked whether they thought their governments were doing enough to deal with the pandemic, almost half said no.
A third of Nigerians think their government should do more
Two-thirds of Tanzanians and more than half of Nigerians questioned for the BBC survey said HIV/Aids was their top concern, a long way ahead of financial security and crime.
In South Africa, where more than 20% of adults are infected, nearly half of those asked said crime and lawlessness were the greatest worry - compared to 26% who felt HIV/Aids was.
However, far more South Africans - two-thirds - believed that their government was not doing enough to tackle the pandemic.
In Tanzania, where nearly 8% of people are living with HIV/Aids, a third of those asked felt their government could do more.
The figure was the same for Nigeria, where 6% are HIV positive or have Aids.
The survey asked whether it was possible to catch the virus by sharing a toilet with an infected person, by touching or by sharing personal items such as a cup, a towel or clothes.
Over a fifth of Tanzanians questioned thought it was possible to be infected by sharing personal items - which is not true.
Nigerians knew the most about how HIV/Aids is not contracted compared to the other 14 countries in the survey.
But only 42% of Nigerians in the survey thought that children under 14 should be taught that condoms can protect people from Aids.
In South Africa, where the disease is far more prevalent, 85% were in favour of education about condoms.