What Is HPV?
The Human Papilloma Virus is a very common virus, and nearly all individuals are infected with this DNA virus at some point in their lives. HPV infects epithelial cells, cells that cover the body surface. There are over 100 different HPV types, and some have a preference for mucous membranes like those found in the genitals, whereas other types prefer cornified areas or areas of the skin like those on the hands and feet.
How Is It Spread?
Depending upon the strain of the virus, the HPV virus can be spread by skin to skin contact and during sexual intercourse to result in genital HPV lesions. For warts present on the skin, HPV can be spread via surfaces such as non-slip surfaces in showers or swimming pool areas. Although most HPV infections can be cleared by the immune system, certain strains have been correlated with the development of benign, precancerous, and cancerous lesions such as:
- Cervical, Vaginal, Vulvar Cancer
- Penile Cancer
- Anal Cancer
- Oropharyngeal Cancer
- Cutaneous and Genital Warts
High-risk strains are linked to the development of pre-cancers and cancers, whereas the low-risk strains result in cutaneous and genital warts.
How Does HPV Relate to Warts?
Warts are caused by one of the many different types of HPV and appear as small growths on the body. Based on their location, they can be characterized as common, palmoplantar, flat, or genital. The most common warts are those presenting on the hands and feet caused by HPV type 1,2,4, 27 and 57, whereas genital warts are caused by low-risk HPV types 6 and 11. These lesions can be difficult to treat, often requiring the combination of several treatments. Nearly 80% of warts regress spontaneously within 2 years, however, this time period may vary depending upon the immune status of the HPV infected individual, the type of HPV they are infected with, the amount of time they have had warts, and the number of warts that they have.
What Is the HPV Vaccine?
The HPV vaccine comes in different forms that are currently approved in the US to protect against specific low and high-risk strains of HPV. The nonvalent HPV vaccine protects against nine different HPV strains, whereas the quadrivalent HPV vaccine offers protection against four HPV strains. There is no live virus in the vaccine, there are only parts of the virus so that you cannot become infected with HPV following administration of the vaccine. This vaccine is indicated in females and males age 9 through 26 as a 2 or 3 dose series to prevent the development of the pre-cancerous and cancerous lesions that can develop from HPV.
Benefits of the HPV Vaccine
The HPV vaccine is the first preventative vaccine against cancer. In the United States, more than 30,000 people are affected yearly by cancer caused by human papillomavirus.  The recommendation for HPV vaccination began in 2006, and since this time, infections with HPV have been significantly reduced. As of 2017, the only HPV vaccine available in the United States is Gardasil-9 which protects against HPV types associated with the development of cancers of the cervix, vagina, vulva, anus, throat, and penis in addition to genital warts.
Gardasil-9 is composed of HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58 which are HPV types that cause around 90% of cervical cancer, the second most common cancer in women worldwide. In addition, these HPV types also cause approximately 95% of HPV-related cancers in men and 90% of genital warts in both men and women.
Although the vaccine is composed of only nine specific types of HPV, some researchers think that one of the HPV vaccine benefits is that that administering the vaccine leads to an immune response that can lead to cross-protection against several other HPV strains. This means that the HPV vaccine may protect against more types of HPV than included in the vaccine, but this is still considered just a hypothesis. It is important to note that the vaccine offers protection as a preventative measure, and therefore is not used as a treatment for genital warts, precancers, or cancers.
Does the HPV Vaccine Protect Against All Warts?
No, the HPV does not protect against all warts. This vaccine is only intended as a preventative measure against the development of warts caused by HPV types 6 and 11, which are responsible for genital warts. Nevertheless, there is some evidence to suggest the HPV vaccine may have a curative potential in treating non-genital warts. In several studies, researchers have reported clinical cases of warts that were difficult to treat in several patients after receiving the HPV vaccine. [8-17] Although there are only a few of these cases, the results appear promising and further studies on more patients are required to see if the HPV vaccine can be used as an alternative treatment for non-genital warts.