I have had the HPV conversation with a lot of women in my office this month- as pap smear after pap smear has come back abnormal and we move to the necessary steps of follow up. My patients are mostly young women, and my discussion of HPV (human papillomavirus) is usually the first time that they are really learning about this little virus. I am always surprised at how little women know about why we do Paps and how abnormal results can affect them. So here is a primer for Pap smears and HPV- with a little history thrown in!
The cervix is the opening to the uterus, and is found at the very top of the vagina. Back in the day, cervical cancer was the leading cause of death in women, and no one knew why, or how to test for it. Enter Dr. Georgios Papanicolau, who in 1923 was doing research on female guinea pigs and studying vaginal fluid to try to better understand the menstrual cycle. As chance would have it, one of his guinea pigs had uterine cancer and he realized that he could plainly see the abnormal cells under the microscope. It was an "a-ha!" moment for Dr. Papanicolau and a breakthrough in what ultimately became known as the Pap smear. Cells are obtained from a woman's cervix with a brush and studied under the microscope. Abnormal cells signal precancerous changes that can then be treated, thus preventing cervical cancer!
So what happened? Women starting seeing their doctors for annual pap smears, and cervical cancer rates dropped drastically- it was a public health success of tremendous proportions. But the cause of these cellular abnormalities was still a mystery. Then in 1976, German virologist Harald zur Hausen proposed that HPV was the cause of cervical cancer. As is often the case with important scientific discoveries, no one believed him, and he went on to prove his theory in 1983 with the discovery of HPV DNA in cervical cancer tumors. For this important work, he received the Nobel Prize in 2008.
Now we know: HPV is the cause of abnormal pap smears.
When you have a pap that comes back abnormal, it is because of HPV. So how does someone get HPV anyway? It is sexually transmitted. As a matter of fact, HPV is the number one sexually transmitted infection out there. The prevalence is high- it is estimated that between 75-80% of Americans have been exposed to HPV at some point in their lifetime. That means 8 out of 10 people walking around have (or have had) HPV!
Patients ask me all of the time what they can do to prevent getting it, and the answer gets tricky. HPV is small enough that even condoms don’t protect you entirely. The key would be not to have intercourse with anyone who has already been exposed- but how can you tell if someone has been exposed? While men certainly carry this virus, most never know that they have it, because it does not cause any symptoms at all. And it is not something that they are ever tested for, so when someone tells you that they have "been tested for everything", it usually does not include HPV. In most men (except for the HPV strains that cause genital warts), it does nothing. In women, it can cause cervical cancer. It is an inherently unfair setup!
I tell my patients not to stress about an abnormal pap smear, even if it means that they have been exposed to HPV. So have 8 out of 10 people out there! It is so common that I hate to give it the stigma of an std. It is something that people live with, and that their immune systems fight successfully every day. Keep on top of your pap smears and follow ups, and HPV won't interfere too much with your life.
For our younger generation of daughters, consider the HPV vaccine. Once HPV was definitively linked to cervical cancer, the scientific world raced to develop a vaccine, and Gardasil was introduced in 2006. In 2009, it was approved by the FDA for young boys as well, since they are carriers of the virus and transmit it to women. It has been safely given to thousands of young women and men, with the understanding that it is most effective BEFORE the onset of sexual activity, and hence before exposure to HPV. This vaccine is the newest tool in our evolving fight against abnormal pap smears and cervical disease in women.
Dr. Papanicolau would have been proud.
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