The Snowball Effect: HPV

The Snowball Effect: HPV

This article was first published originally on It has been edited slightly.

When it comes to HPV infection, there is a kind of snowball effect. You only need to have had sex with just one other person, who in turn may have slept with another person unknowingly carrying the HPV infection, for the contagious virus to spread.

I’ve only ever been with one other person. How could I get this infection?

My 30-year-old patient asked me this question as I explained the underlying cause of her abnormal cervical smear test results. She had a sexually transmitted infection caused by any one of a group of about 100 viruses, collectively known as Human Papilloma Virus (HPV); it affects the skin, mouth and genital areas of both men and women. Certain strains of HPV known as High Risk HPV are responsible for almost all cases of cervical cancer.

When it comes to HPV infection, there is a kind of snowball effect. You only need to have had sex with just one other person, who in turn may have slept with another person unknowingly carrying the HPV infection, for the contagious virus to spread.

Almost everyone who is or has been sexually active will have an HPV infection at some point in his or her lifetime. It is more common in young people but no demographic is exempt. By building natural immunity, most people will eventually clear the virus from their system. However, for some people, the virus remains dormant in the body and if it is the High Risk HPV, it can cause changes in the neck of the womb (cervix) that may in a small minority of people turn into cancer over several years.

As a consultant gynaecologist with a special interest in cervical pre-cancer, I often hear the following question from women: Why do I not know more about Human Papilloma Virus (HPV) and its relation to cervical cancer? My patient too wanted to know more.

Cervical cancer accounts for two out 100 cancers in the UK every year. However, for women under 35, it is the most common cancer. Types 16 and 18 are strains of High Risk HPV and are responsible for 70% of all cervical cancers; meanwhile, low risk HPV strains can cause genital warts.

Apart from cervical cancer, High Risk HPV can also cause the less common vaginal and vulval cancers in women, and penile and analcancers in men. (People who smoke and drink alcohol in excess are at particular risk of oral cancers).

Women and men who are sexually active do need to be aware of the correlation between HPV infection and cancer as there is help available. The good news is that cervical cancer is mostly preventable.

Is there anyway to prevent getting HPV infection?

Abstinence is the only way of completely avoiding HPV infection. However, this is not practical advice.

Using condoms every time you have sex can significantly reduce the risk of getting HPV infection, as well as other sexually transmitted diseases such as chlamydia and HIV. However, condoms cannot completely eliminate the chances of catching HPV infection as the virus is present on the skin of the genital areas and in the mouth as well. Therefore, oral sex, anal intercourse, open mouth kissing as well as vaginal intercourse all increase the chance of getting HPV infection as does having multiple partners. Most people with HPV have no symptoms.

One cannot get HPV infection from toilet seats, holding hands, swimming or sharing food.

Stopping smoking can also help reduce the risk of HPV progressing to cancer and in eliminating the virus from your body quicker. Excess alcohol should also be avoided.

It is usually not possible to trace the source of the HPV infection, as it may have been lying dormant for several years before any symptoms are experienced.

However, it must be stressed that anyone can get HPV infection so taking precautions and reducing risk factors is sensible.

Can you tell me a bit more about the HPV vaccination?

The HPV vaccination programme is very safe and highly effective, protecting against the two main strains of HPV (Types 16 and 18) that cause the majority of cervical cancer cases. It also offers protection against the viruses that cause genital warts. This vaccine is available to all young girls at ages of 12-13 (year 8) in the UK so that they are protected by the time they are sexually active. Girls can have it free on the NHS up to the age of 18. It usually consists of two injections at least six months apart.

The effects of the vaccine last for at least ten years and probably much longer. It’s estimated that at about 400 lives can be saved every year through vaccination against HPV.

If I have the HPV vaccine, do I still have to have cervical smears?

Yes, it is very important to have regular smears when called by the NHS from the age of 25. If you test negative to High Risk HPV, your risk of cervical cancer over the next three years is negligible.

Smears do not diagnose cancer; they detect changes in the cells caused by the HPV infection. This can guide doctors to offer the right treatment well before cancer develops. The NHS offers smears between the ages of 25-64 years, unless there is a medical reason to do them more frequently. Sadly, one in three women between 25-29 years don’t attend their smear tests.

Self-testing is an area that is being developed to try and target those women who don’t come forward for routine cervical smear testing because they find these tests intrusive or don’t have the time to go to their doctor.

If I have an HPV infection, does it mean I will get cervical cancer?

No, it doesn’t. It just means that you will need closer follow up and a small number of women may need treatment to prevent precancerous cells progressing to cancer. Cervical cancer is very rare in women under the age of 25.

Should I tell my partner I have an HPV infection?

There is no straightforward answer since there is no treatment or method of testing HPV in men. Practising safe sex is always the best way forward as condoms can significantly help in preventing transmission and reinfection. Vaccination is not yet available for boys on the NHS.

My patient had missed HPV vaccination at school as it was not in place then. She would have to pay for it. I advised her to consider having the vaccine even at this stage to protect herself from the more serious strains of High Risk HPV.

If you have any concerns about HPV or smears, it’s always best to speak to your GP who will be able to guide you.