Human papillomavirus (HPV) and immunization

What is HPV?#

Human papillomavirus (HPV) is a very common virus that is spread through sexual contact. Most people do not have any symptoms, and the virus often clears from the body on its own. For some people, however, HPV leads to genital warts or, less commonly, certain cancers.

HPV can affect anyone who is or has been sexually active, even after a single sexual contact. It is very common to be infected with one or more types of HPV soon after sexual activity begins, and around nine out of ten people have HPV at some time in their lives.

There are over 200 strains of HPV. Around 40 of them can affect the genital area, which includes the vagina, vulva, cervix, penis, scrotum, anus and rectum. HPV is usually spread by skin-to-skin contact during sex, including genital-to-genital contact, vaginal, anal and oral sex, and sharing sex toys.

Symptoms#

Many people with HPV have no symptoms, and the virus can clear without you ever knowing you had it. Signs of HPV, including warts, may not be visible, may be in places that are hard to see, or may not appear at all, so it is possible to be infected without knowing.

Symptoms can be vague, but see your doctor or a sexual health clinic if you notice:

• lumps, pain or itching in your genital area
• unusual vaginal or anal bleeding
• pain during sex
• any unusual changes to the skin around your genitals

You can be infected with more than one type of HPV in the genital area. You cannot get genital HPV from warts on other parts of the body, such as the hands and feet.

HPV and sexual health#

Because HPV is so common and often has no symptoms, it is important to look after your sexual health:

• practise safer sex by using barrier protection, such as external or internal condoms and dental dams
• have regular sexual health checks if you are sexually active, including testing for sexually transmissible infections
• see a doctor or nurse if you notice any unusual changes around your genital area

Barrier protection reduces the risk of HPV but does not remove it completely, because the virus can affect areas that are not covered.

HPV and cancer#

Some types of HPV are considered low-risk and may cause genital warts, while other, high-risk types can lead to certain cancers. These include cervical cancer, other cancers of the genital area (such as vaginal, vulvar, anal and penile cancers), and some cancers of the mouth and throat.

It is relatively uncommon for HPV infection to lead to cervical cancer, and not all types of HPV cause it. Some types can infect the cervix and cause abnormal cell changes (dysplasia) if the virus does not clear naturally. Over a long period, often 10 years or more, these changes can sometimes develop into cancer.

Cervical screening#

Cervical screening helps reduce the risk of cervical cancer by checking for HPV or for changes in cervical cells. Screening is recommended at regular intervals for women and people with a cervix, even if you feel healthy or have had the HPV vaccine, because the vaccine does not protect against every type of HPV that can cause cervical cancer. Some people who have had a hysterectomy may still need screening and should discuss this with their health provider.

Immunisation against HPV#

The HPV vaccine protects against the types of HPV that cause most HPV-related cancers, as well as the types that cause most genital warts. The vaccine prevents disease caused by HPV but does not treat an existing infection. If you have symptoms of an active HPV infection, see a health professional.

The vaccine does not contain live HPV. Instead it resembles the virus closely enough that the body produces antibodies that help prevent future infection.

Who should be vaccinated#

The HPV vaccine is recommended for people of all genders and works best when given to young people before they become sexually active, because that is when the body produces the strongest immune response. It is commonly offered in early adolescence.

Some older adults who were not vaccinated earlier may also benefit and should talk to their doctor, as may people who have weakened immune systems. People who are already sexually active have often been exposed to HPV, so the vaccine may offer less benefit, but individual circumstances vary and your doctor can advise you.

How many doses#

The number of doses needed depends on your age and your immune status. Many people need only a small number of doses, while people with significantly weakened immune systems may need additional doses. Talk to your doctor or immunisation provider about the schedule that is right for you or your child.

How the vaccine is given#

The HPV vaccine is given as an injection into the deltoid muscle of the upper arm.

Pregnancy and breastfeeding#

The HPV vaccine is not recommended during pregnancy. Tell your immunisation provider if you are pregnant or think you could be pregnant on the day of vaccination. The vaccine can be safely given to people who are breastfeeding.

Effectiveness and safety#

HPV vaccination programs have been shown to reduce rates of HPV infection, genital warts and pre-cancerous changes of the cervix. Long-term studies suggest the protection is strong and long-lasting, and is expected to last for many years.

The vaccine has undergone rigorous testing to confirm that it is safe. As with all medicines, it can have side effects, but these are usually mild and settle on their own.

Before vaccination#

Before having the HPV vaccine, tell the doctor or nurse if you:

• are pregnant or planning to become pregnant
• are unwell, especially with a fever
• have allergies to any medications or substances
• have had a serious reaction to any vaccine or to any part of a vaccine
• have a condition, or are having treatment, that lowers your immunity
• are taking any prescription or over-the-counter medicines

Possible side effects#

Side effects are usually mild and temporary, and may include:

• pain, redness or swelling at the injection site
• a low-grade fever
• mild headache
• mild nausea

To ease discomfort, drink extra fluids and wear light clothing. Paracetamol (acetaminophen) can help with fever or with pain at the injection site; check the label for the correct dose or ask your pharmacist if you are unsure. A cold compress on the injection site can also help. Discomfort at the site usually lasts only a couple of days and improves on its own.

There is a very small risk of a serious allergic reaction (anaphylaxis) after any vaccine, so the person being vaccinated should stay at the clinic for at least 15 minutes afterwards in case treatment is needed.

If a side effect is unexpected, persistent or severe, or if you are worried, see your doctor or immunisation nurse as soon as possible, or go directly to a hospital. It is important to seek advice for anyone who is unwell, as the cause may be another illness rather than the vaccine. Ask your immunisation provider how to report any side effects.

Other immunisations you may need#

The other immunisations you may need depend on your health, age, lifestyle and occupation (sometimes called your HALO). Talk to your doctor or immunisation provider if you think you, or someone in your care, may have health, age, lifestyle or occupation factors that make further immunisation worthwhile.

Key points#

• HPV is a very common virus spread through sexual contact, and most people will have it at some time in their lives
• Most people have no symptoms, and the virus often clears on its own
• Some high-risk types of HPV can lead to cervical and other cancers, while other types cause genital warts
• The HPV vaccine works best before someone becomes sexually active and is recommended for all genders
• Cervical screening is still important even after vaccination, because the vaccine does not cover every cancer-causing type

Where to get help#