HPV vaccination: what it protects against

What is HPV?

HPV, or human papillomavirus, is a common virus, primarily passed on by skin and sexual contact. Most people meet it at some point, and most infections resolve without causing harm.

There are many types of HPV, and only a few are high risk and can cause cancer. Those few are the ones that can persist rather than clear.

A persistent high risk infection is what matters. Over years it can slowly change cells in the cervix and elsewhere, first causing precancerous changes and, in some cases, eventually cancer.

Screening, meaning a Pap smear and HPV test, or the two combined, exists to catch those changes early. The vaccine works a step earlier, by lowering the chance of the infection itself.

What the vaccine does

The vaccine trains your immune system against the highest risk HPV types. It lowers the chance of infection with those types.

Large studies link vaccination to far fewer precancer changes. The effect is greatest when it is given before any exposure.

What the real world data show

This is not only theory from trials. Countries that vaccinated early are already seeing cervical cancer rates fall.

The drop tracks with how many were vaccinated, and how young. The signal is consistent across large national datasets, and follow up now runs well over a decade.

Which cancers it involves

Most people know the cervical link, and that is the largest one. But high risk HPV is tied to more than the cervix.

These include anal, throat and other genital cancers, affecting both women and men. That is why HPV vaccination matters to both sexes.

Who it is for

Does it replace screening?

Cervical screening remains the standard, vaccinated or not. The vaccine covers the highest risk types, but not every type, and screening catches the changes that slip through.

How many doses

The number of doses depends on your age at the first shot. Younger teens often need fewer than older starters.

Your doctor or the school programme will advise on the schedule. It is set to give the strongest protection for your age.

If you missed it as a teen

You can still be vaccinated as an adult in many cases. The benefit is smaller if you have already been exposed.

Even so, some adults can still benefit. Ask your doctor whether vaccination still makes sense for you.

Is it safe?

It has a long, well studied safety record across many countries. The common effects are a sore arm and short lived aches.

Serious effects are rare. Safety monitoring has continued since it was introduced, across millions of doses.

Common myths

How long protection lasts

Protection appears to last for many years, and current evidence does not show a need for booster doses.

Research is still tracking the oldest vaccinated groups. So far the results have been reassuring.

How HPV spreads

HPV passes through skin and sexual contact. Condoms lower the risk but do not remove it, since they do not cover all skin.

It is extremely common, and carrying it is nothing to be ashamed of. In most cases the body clears it within one or two years.

Where to get it

In Singapore, the school programme offers it to eligible girls. Adults can arrange it through a GP or clinic.

Your doctor can advise on which vaccine and schedule suits you. Availability and cost vary, so ask when you book.

The bottom line

The HPV vaccine lowers the risk of several cancers. It works best given early, before exposure.

It works with screening, not instead of it. Discuss the right timing with your doctor.