If a very small amount of high risk hpv virus enters our body, it is often cleared by immunization or the virus becomes dormant?

"High risk" HPV sub-types are discovered by pap smears and lab determinations of abnormal cell types. Although immune system can attack circulating "high risk viral particles", such can effectively continue to multiply and can change to early cervical cancer if not treated (cryo therapy or surgical removal of a portion of the cervix via colposcopic examination). See your gyn for an exam.