What Is Human Papillomavirus?

The most common STD in the world today is a group of viruses known as human papillomavirus, or HPV. According to the U.S. Centers for Disease Control and Prevention (CDC), nearly eighty million Americans (about one in four) were actively infected with HPV in 2018 (the most recent data available), and forty-two million were infected with strains of HPV that cause disease at that time. Canadian health experts estimate that 70 percent of Canadians will be infected with HPV at some point in their lives. HPV has become so widespread that as many as thirteen million new cases of HPV occur each year in the United States.

If you are a teenager and are reading about HPV for the first time, you may rightly wonder what this means to you, where you can go for more information, and what steps you can take to protect your health. STDs such as HPV are sometimes difficult to talk about. Teens are often embarrassed because of the stigma associated with STDs. It is very important to address this subject, however, since many STDs, including HPV, may have no obvious symptoms. If you are not aware of the facts, it is often difficult to tell if you’re in need of treatment or if you have been infected. In fact, one reason HPV and other STDs are so easily spread is that a lot of people don’t even know that they are infected and are infecting others without realizing it.

Learning about HPV is a valuable first step toward overcoming any awkwardness you may feel about STDs. It will also help you make responsible decisions about your health and sexual behavior.

HPV Defined

Human papillomavirus, or HPV, is a group of viruses that cause an infection that affects the skin and mucous membranes of the body. A virus is a microscopic organism made up of protein and genetic material (DNA). Viruses are so small that they can only be seen with very powerful tools called electron microscopes. Viruses can get into the body when it comes into contact with the body of an infected person. In the case of HPV, one person can give the virus to another during sex or other types of activities. Once inside the body, viruses multiply by making copies of themselves.

HPV actually refers to a group of over two hundred different viruses. Over one-third of the known HPV viruses are sexually transmitted. HPV is sometimes called the “wart virus” because it is most often associated with the warts that some strains can cause on the genitals or on other parts of the body.

Virus particle View Larger Image From http://nobelprize.org/nobel_prizes/medicine/laureates/1993/illpres/genes-in-pieces.html

It is more common for people to develop HPV without symptoms than it is for them to exhibit signs of genital warts. HPV infections that can cause warts—whether hidden or obvious—are classified as low-risk infections because they usually do not lead to cancer. Other higher-risk strains of HPV (strains 16, 18, 31, 33, and 45 of the virus), while not likely ever to cause genital warts, are linked to certain cancers in women and other cancers in men. For example, certain strains of HPV are now known to be the leading cause of cancer of the cervix (the portion of the uterus that opens into the vagina) in women. HPV is also linked to cancers of the penis in men, and of the anus and mouth in both men and women.

When HPV develops into genital warts (also known as venereal warts), the growths can grow on, in, or around the anus, inside the vagina, or on the penis. Genital warts may also appear on the outer pubic skin, the groin area, and the areas near the inner thigh. In some cases, genital warts can become quite large and grow to resemble cauliflower. However, this is not always the case, and warts may be overlooked if they are very small, flat, flesh-colored, or painless. Symptoms such as itching, bleeding, or pain are not common but can occur.

Although genital warts are an obvious sign of HPV infection, many who contract HPV never develop genital warts. In fact, most people who become infected with HPV don’t even know they have it. This is because the body’s immune system holds HPV at bay, leaving no visible symptoms, even though the infection is still present within the body. This means that although you have no symptoms or wart growths, you could still infect others with HPV. This also means that a person can be infected by their partner even if that partner shows no visible signs of HPV infection.

The strains of HPV that lead to genital warts are different from those that produce warts on the hands and feet.

What Exactly Are Warts?

Warts on hands View Larger Image © E.Nelson/Custom Medical Stock Photo

Warts have an interesting history and have been written about for centuries. Known to the Romans as verrucas, genital warts were suspected to be sexually transmitted as far back as A.D. 25. The suggestion that warts were caused by a virus came much later, in nineteenth-century England. It was only after 1950, however, when papillomavirus particles were finally analyzed under a microscope, that scientists accepted the virus connection. We now know of, and have isolated, every variety of wart, both genital (venereal) and common.

When people speak of warts, they are generally speaking of one of the following:

• Plantar warts: Warts that appear on the soles of the feet and are sometimes dotted with tiny black or red dots, which are clotted blood vessels. When plantar warts grow in a cluster they are known as mosaic warts.

• Flat warts: These warts are also commonplace and appear on the face, neck, forearms, hands, or fingers and are flesh-colored, small, and flat. Flat warts tend to grow in large numbers of about twenty to one hundred at a time.

• Common warts (also called seed warts, periungual warts, or subungual warts): Like the name suggests, these small warts appear to be ordinary and often show up under or around the fingernails or toenails, or on the hands, arms, and legs, especially in children.

• Genital (or venereal) warts: These warts are highly contagious and spread by skin-to-skin contact. They are normally raised, fleshy growths found in the genital or anal area.

HPV thrives in the cells of the skin. Because of this, HPV can be spread through contact with infected pubic skin or other areas that condoms don’t cover. Condoms provide some protection and should be used, but wearing a condom during sex is not a total safeguard against HPV. Condoms do, however, offer an effective barrier against other STDs and pregnancy.

Traditionally, condoms have been made from latex. But you may have seen newer polyurethane condoms too. Some people claim that polyurethane condoms are more sensitive than latex ones because they are thinner in texture. But studies show that polyurethane condoms are not as effective in protecting against pregnancy and sexually transmitted diseases. Polyurethane condoms are more likely to slip off the penis during withdrawal and also to break. The bottom line is, unless you are among the small number of people allergic to latex, latex condoms are a far safer option.

The presence of HPV in the skin may result in cell changes that can be seen only with the use of a high-powered lens. HPV can also live in the skin without causing any cell alteration at all. These two factors can make it hard to know when you’ve been infected; and so, many sexually active people unknowingly pass on the virus to someone else. As a result, HPV has become so common that the National Foundation for Infectious Diseases (NFID) estimates that 80 percent of sexually active people in America will have an HPV infection at some point.