Photo: Getty Images
There are three viruses known to cause cancer, one of them is HPV or Human Papillomavirus. While this virus has been in the news lately, it has actually been around for several hundred years.
HPV is typically referred to as an STI (sexually transmitted infection) because it is transferred, for the most part, during sexual activities. I say activities because it does not require actual intercourse to spread the virus but merely skin-to-skin contact predominantly with mucous membranes such as occur in the vagina, mouth and anus.
HPV has an incubation period of approximately three months after which, symptoms may appear. However, this is often called the symptomless disease because, more often than not, it produces no symptoms at all. The body’s immune system can then suppress the virus and it can remain dormant in the body for weeks, months and even years. Because of this, it can return again later in life for a multitude of reasons not fully understood.
Some of these may include a decrease in the person’s immune system or an increase in viral load, the amount of the virus the body is exposed to. Reducing the viral load is one reasons why wearing condoms, even if in a monogamous relationship, remains important.
The human papillomavirus has what are referred to as high and low risk strains. A strain refers to the same virus with a slight difference. There are more than 150 strains of HPV documented to date. Some of these low risk strains cause such things as the warts found the hands and plantar warts on the feet. Other low risk strains cause genital warts.
High risk strains of HPV, thirteen of which are regularly tested for, can, if persistent, result in dysplasia or a changing within the normal cells. Dysplasia can occur in varying degrees basically low, intermediate and high risk for causing cancer.
Dr. Ralph Richart, M.D., and pathologist at Columbia Presbyterian Medical Center in New York City developed the term intraepithelial neoplasia (IN) meaning an abnormal change within the epithelial layers of the skin. The letter symbolizing the part of the body affected comes before such as CIN for cervical intraepithelial neoplasia and so on.