The number of HIV/Aids cases diagnosed in Norfolk, Suffolk, and Cambs has risen by 500%, according to the region's Strategic Health Authority.
In 1999, there were 29 cases of the virus across the three counties. But in 2003 the number of people infected had increased to 146, the report revealed.
Public health director Dr Tony Jewell said the numbers had increased because people were not practising safe sex.
It costs the NHS £250,000 to treat each HIV patient during their lifetime.
A similar increase can be found across Northamptonshire and Milton Keynes.
Condom advice
Dr Jewell said: "When the HIV/Aids epidemic first started in the late 80s to early 90s it was largely confined to intravenous drug users and the male gay community.
"What we are now seeing is a growth area among the heterosexual community. Ages 25 to 35 is where the greatest incidence occurs.
"The message really is be very careful about alcohol. If you're drunk the risk is that you won't have safe sex."
Condoms were the best form of protection against sexually-transmitted infections (STIs), he added.