9 per cent of women have HPV infections: Study

One in 10 healthy women here is infected with the human papillomavirus (HPV), a new study has found.

And half this group have high-risk strains normally associated with cervical cancer.

The study of close to 900 women by the Singapore General Hospital (SGH) also found that the infection was most common in those aged between 20 and 24. A fifth of them had high-risk strains.

"This is the group of women that never thinks of cancer," said Professor Tay Sun Kuie, a senior consultant at the hospital's obstetrics and gynaecology department.

"And yet, it is at this young age that the seeds of the risk of cancer are planted."

The study, published in the International Journal of STD and Aids in March, is the first to pinpoint how common HPV infections are here.

Worldwide, the figures range from 8 per cent in Europe to 22 per cent in Africa.

There are many strains of the virus, some 30 of which are transmitted by sexual contact.

The more benign strains cause diseases like genital warts, while malevolent ones are usually associated with cancer.

Cervical cancer is of the greatest concern as it is among the top 10 cancers in Singapore women. About 200 new cases are diagnosed every year, said Prof Tay, and one woman dies of it every three days.

But he added that those with HPV infections should not worry unduly as the body naturally gets rid of over 90 per cent of such infections on its own.

Also, the chances of them leading to cervical cancer are less than 1 per cent.

Nonetheless, this is something that women who have tested positive for the virus must be aware of, he said, because it means they are at risk of abnormalities in later years, and screening tests every three years are critical.

In the SGH study, those with fewer years of formal education and multiple sexual partners were more likely to be infected.

No infections were detected in women who had not engaged in sexual activity.

Prof Tay explained that the number of infected women peaks in the 20 to 24 age group. This is because by middle age, most HPV infections would have been naturally cleared by the body.

Prof Tay however noted that sometimes tests may not be able to pick remaining traces of the virus.

While men can get penile or anal cancer from other strains of the virus, they are rare and not a major concern, he said.

"Cervical cancer can be prevented if women go for screening," stressed Prof Tay.

"But a lot of women don't, and they are putting themselves at risk."

He also encouraged parents to get their daughters vaccinated, saying: "Prevention ought to be as early as possible."

linettel@sph.com.sg

HOW MANY INFECTED

Findings from the Singapore study

9.3 per cent of women were infected by the human papillomavirus (HPV)

5 per cent were infected by a high-risk strain, which can lead to cervical cancer

26.1 per cent of women aged between 20 and 24 were infected by HPV

Worldwide prevalence of HPV infection

Africa: 22.1 per cent

Central America and Mexico: 20.4 per cent

North America: 11.3 per cent

Europe: 8.1 per cent

Asia: 8 per cent

Facts about HPV

More than 100 strains, about 30 of which are transmitted via sexual contact

14 strains are high-risk and known to cause cancer

Infection rate tends to be higher among women with more sexual partners

Women can still be infected even if they have protected sex

This article was first published on Oct 30, 2014.
Get a copy of The Straits Times or go to straitstimes.com for more stories.