After a few strained conversations with people in the education industry I've come to the conclusion that Mia's HIV positive status is really really important.
In the UK, lots of kids aren't taught about this stuff in schools. It's not mandatory, each school determines what sex education is taught and there's not a government line. If it was gonna come in anywhere, you'd assume that it comes under Personal, Social and Health Education, PSHE. Stuff like relationships, pregnancy and other STDs are covered in this area. But HIV and AIDs? Not necessarily.
A lot of schools cover HIV and Aids in the science curriculum, but I'm not sure how much it goes into the social side of it or if it just covers how the disease works, and I don't know if it's enough. As I said, strained conversations so I couldn't find out much more.
Basically, if kids aren't getting their information from schools and you don't what they're getting from their parents, then if they can read it about from another source, that provides knowledgeable and accurate information, (as I think Judd Winnick's Mia is), then that's really fucking essential.