Human papilloma virus is the most common sexually transmitted infection in adults, and it is ubiquitous. In fact, it is believed that nearly every sexually active person will eventually contract it. HPV is usually asymptomatic, and in most cases it goes away on its own without causing lasting harm. However, roughly a quarter of the more than 150 known types of the virus are associated with the various forms of warts—often on the foot as well as more intuitively obvious places—that give the virus its name, and four types significantly increase the risk of genital cancers, with an additional dozen or so raising the risk to a lesser degree. Two of those types are estimated to be responsible for 70 percent of cases of cervical cancer, and nearly all cases can be traced to some form or other of HPV.
The good news is, that makes genital cancers among the easiest types to prevent—and not just in principle. Vaccines for human papilloma virus may make it possible to reduce global cervical cancer deaths by two-thirds, and may allow genital cancers to be almost entirely wiped out in the space of only two or three generations. The vaccine is most effective when administered to someone who is not sexually active; independent of that, it is less effective in adults than in teenagers regardless of sexual activity, meaning it is not infrequently given when requested by parents on behalf of their children.
Although there have been a handful of well-publicized instances, this has met with very little resistance from parents—who are generally more than happy to have their children protected against a dangerous, often deadly disease at the cost of their own discomfort. However, in a recent survey, nearly half of parents report that their pediatrician had not even mentioned the HPV vaccine, and that they hadn’t realized this protection was available. This omission on the part of doctors may well have contributed to what the Centers for Disease Control and Prevention called an "unacceptably low" rate of HPV vaccination. Doctors appear to address HPV vaccination based on a perception of whether the child is likely to be sexually active soon. However, it is recommended that pre-teens and teenagers get vaccinated regardless of sexual activity, now or in the future.