News & Views: Three Questions about HPV Transmission

1. If I have HPV, can I spread it by kissing?
2. If my partner has genital warts and I am infected following oral sex, where will my infection occur?
3. If I have a positive Pap test, does that mean I also have oral HPV?

If your patients ask, do you know how to answer the above questions? Through prevent-HPV.org, we get many questions, and, often, they are related to how the virus spreads. People are alarmed by a positive test result, confused if that result follows several years in a monogamous relationship, and concerned for themselves and their partners. So, this Cervical Health Awareness Month, we thought a quick refresher on HPV replication and transmission might be helpful. Read on to check your answers to the above questions and find resources to share with patients who might have questions.

HPV replication

Like other viruses, HPV reproduces itself in human cells. The cell type of choice for HPV is epithelial cells. HPV types that cause anogenital and oropharyngeal cancers and genital warts infect epithelial cells that line the mucosal surfaces of these areas of the body. HPV viral replication does not lead to immediate cell death (unlike viruses like rotavirus), but rather causes infected cells to continue replicating. The infection typically starts at the basal, or bottom-most, layer of the epithelium. As the epithelial cells reproduce, each layer of cells is pushed up until it reaches the surface and sloughs. During this process of cell death and shedding, viral particles are released, setting the stage for viral transmission.

In about 90 percent of people, the immune system works locally to keep viral gene expression in check and eventually clears the infection. But, viral clearance can take months or even years. In rare cases, the immune system will keep the infection “in check,” but will not completely eliminate the infected cells. So, if the immune system weakens, the virus will gain the upper hand and again ramp up gene expression. During a prolonged infection, viral genes might integrate into the cellular genome, paving the way for oncogenic transformation of the cell.

This viral life cycle is also characterized by the fact that the virus remains in the area of the original infection. The virus does not travel through the bloodstream, so infections do not occur at distant sites.

HPV transmission

Because viral particles are released as cells die or slough at mucosal epithelial surfaces, intimate interactions make transmission likely. Further, micro-abrasions that expose the basal layer in non-infected partners provide an opportunity for infection. While sexual intercourse is the primary means of transmission, genital-to-genital interactions, oral-to-genital interactions, or deep (French) kissing can also spread the virus.

Answers to the questions

1. If I have HPV, can I spread it by kissing?
   While kissing one’s child or parent is not likely to spread the virus, kissing intimately can
2. If my partner has genital warts and I am infected following oral sex, where will my infection occur?
   Someone infected with HPV during oral sex will have HPV in their mouth or throat. They could be infected in both areas if their intimate activities involved exposure of both areas, but the virus would not travel from the person’s mouth or throat through their bloodstream to their genital region.
3. If I have a positive Pap test, does that mean I also have oral HPV?
   Someone with a positive Pap test may happen to also be infected orally, depending upon the nature of their sexual encounters. But a positive Pap test does not say anything about whether HPV is present in another part of the body.

Resources for patients related these topics

The VEC’s HPV question and answer page can be found at www.prevent-hpv.org. The page contains answers to about 80 questions related to HPV transmission, symptoms, testing, vaccination and more.

The January 2019 issue of Parents PACK featured two animations from the Vaccine Makers Project related to how viruses infect cells and replicate as well as a new Science Made Easy video of Dr. Offit discussing how different viruses behave when they infect people. In the video he describes three different types of infections caused by viruses, including HPV.

HPV resource library

The National HPV Vaccination Roundtable has a resource library that contains a variety of materials related to HPV, including fact sheets, podcasts, slide presentations and more.