Re: the connection with cervical screening and HPV
The pap smear has an accuracy rate ranging from 40-80% (in detecting abnormalities which end up being cancer).
The HPV/dna test has an accuracy rate of something like 92%.
The two tests together, on women over 30, has an accuracy rate of greater than 97%. (Maybe it is 99%, I can't exactly remember).
HPV is considered an STD because it is transmitted during intimate/sexual contact (not just sexual intercourse). It is also the most common STD; greater than 80% of women (aged 50+) have been exposed to HPV at some point in their lives.
The pap is only a screening tool; it isn't diagnostic. With borderline abnormalities, a colposcopy will give the doctor a better idea of what is going on with the outer cervix.
My suggestion is that if a woman is high risk HPV positive and is over 30, then if/when she needs a colposcopy I suggest she also ask for an ECC (endocervical curettage). It is the only non-surgical way for a doctor to sample the cervical canal (where up to 30% of cervical cancers are found).
Does that answer some of your questions?