That ol' myth has been shot down many times.
Realize that it was fake statistics to create that...for example, they have changed the definition of AIDS many times, along with HIV infections, and "heterosexual," etc. Male immigrants from certain Africa nations were suddenly automatically categorized as "heterosexual" even if they were having sex with men. The majority of IV drug users getting HIV are heterosexual, but why is that relevant to the sex arena?
Truth is, it's very rare for heterosexuals to contract HIV without IV drug use or without homosexual contact (or contact with someone who is involved in such behavior).
How about just providing instruction to kids that "adult" and forbidden activities are to be avoided?