HPV Test vs Pap Smear: What's the Difference?

Cervical cancer is one of the few cancers that can almost always be prevented, because the changes that lead to it are slow and can be found years in advance. Two tests are used to find them: the HPV test and the Pap smear (Pap test). People often use the names interchangeably, but they look for different things. This guide explains the difference, how often to screen, and what to do with the result. Ovio offers an HPV test at home in Bangkok.

What Is HPV?

Human papillomavirus (HPV) is a group of more than 100 related viruses, and the most common sexually transmitted infection: most sexually active people catch it at some point. It spreads through skin-to-skin contact in the genital area, during vaginal, anal and oral sex. Condoms lower the risk but don't remove it, because they don't cover all the skin.

• Low-risk types, such as HPV 6 and 11, can cause genital warts: soft, skin-coloured or pink bumps, sometimes shaped like a small cauliflower. They don't cause cancer.
• High-risk types, above all HPV 16 and 18, can cause changes in the cells of the cervix that may, over many years, become cancer. They can also cause, much more rarely, cancers of the anus, penis, vulva, vagina and throat.

Apart from warts, HPV causes no symptoms. The immune system clears around 9 in 10 infections by itself, usually within two years. The risk comes from the small number of high-risk infections that persist, which is why screening matters even when you feel completely well.

What Is Cervical Cancer?

Cervical cancer develops in the cervix, the lower part of the womb (uterus) that opens into the vagina. It starts when cells in the lining of the cervix change abnormally and, over time, become cancerous. According to the World Health Organization, more than 95% of cervical cancers are caused by HPV, most often types 16 and 18. It usually takes 15 to 20 years from infection to cancer, so there's plenty of time for screening to find and treat the changes.

Early cervical cancer often has no symptoms. As it progresses, it can cause bleeding after sex, between periods or after the menopause; bloodstained or unusual-smelling discharge; and pain in the pelvis or lower abdomen. These symptoms have many other causes too, but they always need checking by a doctor, whatever your last screening result.

HPV Test vs Pap Smear: What's the Difference?

Both tests use a sample of cells from the cervix, often taken in the same few seconds during a speculum examination. The difference is what the lab looks for.

Because it finds risk earlier and misses fewer cases, the HPV DNA test is now WHO's recommended primary screening test. The Pap smear still has an important role: it's used to follow up a positive HPV result, to decide whether a closer examination of the cervix (colposcopy) is needed. Some countries use both together, called co-testing.

Which Test Do You Need, and How Often?

Screening is for anyone with a cervix who has ever been sexually active, including after the HPV vaccine. Guidelines differ slightly between countries, but they usually look like this:

• Under 25: HPV is very common and usually clears by itself, so HPV testing isn't advised. In the US, a Pap smear every 3 years is recommended from 21.
• 25 or 30 to 65: an HPV test every 5 years is preferred. WHO recommends HPV DNA testing from 30, every 5 to 10 years. A Pap smear every 3 years, or co-testing every 5 years, are alternatives.
• Living with HIV: start from 25 and screen more often; WHO advises an HPV test every 3 years.
• Over 65: you can usually stop if your recent results have been normal. Ask your doctor.

Your doctor may advise a different schedule based on your history, previous abnormal results or treatment of the cervix. There's no routine HPV screening test for men; genital warts are diagnosed by a doctor examining them.

HPV Testing in Bangkok

HPV tests and Pap smears are available at hospitals and clinics across Bangkok. If you'd rather not sit in a clinic waiting room, Ovio's at-home STI testing brings a doctor to your home, condo, hotel or office at a date and time you choose, for Thai and international clients.

Ovio's HPV test checks for 32 HPV genotypes, including the high-risk types 16 and 18, for ฿4,990. The doctor explains your result and, if it's positive, what follow-up you need. If you're also wondering about other infections, see which STI tests should I get?

Frequently Asked Questions

Does an abnormal Pap smear mean I have cervical cancer?

Almost never. Abnormal cells range from minor changes that often go back to normal by themselves to changes that need treatment, which is simple and effective at this stage. Your doctor looks at how abnormal the cells are, your HPV result, your age and your history to decide on the next step.

My HPV test is positive. What happens next?

A positive result is common and usually temporary. If it's HPV 16 or 18, the next step is usually a colposcopy. For other high-risk types, a Pap smear on the same sample, or a repeat test in a year, is common. Your doctor will explain which applies to you.

Is an HPV test or Pap smear painful?

It shouldn't be. When the speculum is inserted you may feel pressure or mild discomfort for a minute or two. If you've had pain before, feel anxious about the examination or find the muscles tighten, tell the doctor first: they can use a smaller speculum, change your position and go at your pace.

I've had the HPV vaccine. Do I still need screening?

Yes. The vaccine prevents the types most likely to cause cancer, but not every high-risk type, and it doesn't clear an infection you already had. Keep screening at the recommended ages.

How can HPV infection be prevented?

The HPV vaccine is the most effective protection. It works best before sex begins, which is why WHO's main target is girls aged 9 to 14, but many programmes also vaccinate boys and young adults, and older adults can ask their doctor. Condoms lower the risk, and regular screening finds problems early.