Are all HPV types associated with an increased risk of cervical cancer?

No, there are more than 100 genotypes of HPV but only 14 are considered high-risk for cervical cancer.

What exactly is cervical cancer?
Cervical cancer occurs when malignant (cancer) cells form in the tissues of the cervix. The cervix is the lower, narrow end of the uterus (womb where a fetus grows). It connects the vagina (birth canal) to the upper part of the uterus (1). More information about cervical cancer is available here.

What is HPV?
Human papillomavirus (HPV) is a common sexually transmitted DNA virus. It is transmitted through vaginal, anal, or oral sex, and can be spread even when an infected individual does not show any symptoms. It is the most common sexually transmitted disease in the United States, with an estimated 43 million HPV cases in 2018. Almost every non-vaccinated sexually active individual will get HPV at some time in his or her life (2). See our previous article “HPV Quick Facts” for more information.

Which HPV genotypes are associated with an increased risk of cervical cancer?
Genotypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68 are considered “high-risk” genotypes. Nearly all cervical cancers are caused by a persistent infection with one of these genotypes. The persistent viral infection can cause changes in the cervical cells, called dysplasia. Although dysplasia itself is not cancer, it can sometimes become cancer (3).

Do the other genotypes cause any health issues?
Some HPV types infect mucosal surfaces, including the “high-risk” types mentioned above, as well as “low-risk” types, which are not linked to cancer risk but can cause genital warts and papillomas (warts) in other mucosal areas (e.g., respiratory tract) instead. Other HPV types are considered cutaneous types as they infect the skin and cause “common” warts on the skin instead, most commonly the hands and feet (4).

Is there a test for HPV?
There are no tests to find out a person’s “HPV status”, as there are so many different types of HPV. However, nucleic acid tests (such as this one) are available to accurately identify individuals who are infected with one of the 14 high-risk HPV strains. Detection of HPV nucleic acid (a positive test result) is indicative of an active HPV infection but does not mean that cervical dysplasia or cervical cancer is present.

Trying to decide if you should take an HPV? Read our previous article “Why should I take an HPV test?” to learn all about the health benefits.

How can I protect myself from HPV?
Anybody who is sexually active is at risk of catching HPV, as HPV is a very common sexually transmitted infection.

Using condoms correctly lowers the risk of catching HPV, but HPV can still infect areas that are not covered by a condom, so condoms do not provide full protection.

HPV vaccination is safe and effective to prevent diseases (including cancer) caused by HPV. It is recommended at age 11 or 12 years, and for everyone through to 26 years, if not vaccinated already. Vaccination for individuals older than 26 years provides less benefit, as most sexually active adults have already been exposed to HPV (2).

Routine screening for cervical cancer with pap smears is also recommended for women aged 21–65 years (2). 

References:
1. Basic information about cervical cancer. CDC. Reviewed Jan 2021.
2. Genital HPV Infection – Fact Sheet. (2021, January). CDC.
3. Cuschieri KS, Whitley MJ, & Cubie HA. (2004). Human papillomavirus type-specific DNA and RNA persistence–implications for cervical disease progression and monitoring. J Med Virol, 73 (1), 65-70.
4. Cervical Cancer. WHO.
5. HPV and HPV Testing. (Revised July 2020). American Cancer Society.