Cervarix (Human papillomavirus vaccine)

How does it work?

Cervarix is a vaccine against the human papilloma virus (HPV). This virus is a sexually-transmitted infection that can cause genital warts, pre-cancerous abnormalities of cells in the female genitals (cervix or vulva) and cervical cancer. The vaccine works by provoking the body's immune response to this virus, without actually causing HPV infection or any of the diseases.

When the body is exposed to foreign organisms, such as viruses and bacteria, the immune system produces antibodies against them. Antibodies help the body recognise and kill the foreign organisms. They then remain in the body to help protect the body against future infections with the same organism. This is known as active immunity.

The immune system produces different antibodies for each foreign organism it encounters. This establishes a pool of antibodies that helps protect the body from various different diseases.

Vaccines contain extracts or inactivated forms of bacteria or viruses that cause disease. These altered forms of the organisms stimulate the immune system to produce antibodies against them, but don't actually cause disease themselves. The antibodies produced remain in the body so that if the organism is encountered naturally, the immune system can recognise it and attack it, thus preventing it from causing disease.

Each virus or bacteria stimulates the immune system to produce a specific type of antibody. This means that different vaccines are needed to prevent different diseases.

Cervarix contains inactivated extracts from two different types of the human papilloma virus: types 16 and 18. HPV types 16 and 18 are responsible for approximately 70 per cent of cervical cancer cases. Cervarix stimulates the immune system to produce antibodies against these types of the virus and is given to prevent the pre-cancerous changes and cervical cancer that they can cause.

Cervarix has also been shown to offer some protection against related HPV types 31, 33 and 45, which are also associated with causing cervical cancer.

At the moment it is not known exactly how long the protective effect of the vaccine will last for. Long term follow-up studies into this are ongoing. Clinical trials have so far shown protection in women aged 15 to 25 years lasting for up to 6.4 years after the first dose. At the moment it is not known if booster doses will be needed.

What is it used for?

Prevention of the following diseases caused by the human papilloma viruses (HPV):

  • pre-cancerous abnormalities of cells in the cervix (CIN 2/3)
  • cervical cancer.

The vaccine has been shown in clinical trials to prevent these diseases in women aged 15 to 25 years. The vaccine has also been shown to produce antibodies against HPV in girls aged 9 to 14 years.

How is it given?

The vaccine is given by injection into the muscle of the upper arm. Three doses are needed. The first two doses are given one month apart and the third dose six months after the first dose.

If more flexibility in this schedule is needed, the second dose can be administered between 1 month and 2.5 months after the first dose and the third dose between 5 and 12 months after the first dose.


  • As with all vaccines, this vaccine may not provide protection against HPV in everyone who has the vaccine. In addition it will not protect against all types of HPV. It will also not protect against any other sexually-transmitted infections (STIs). This means that after having the vaccine you should still practice safe sex and use condoms to prevent STIs.
  • This vaccine should not be used as an alternative to having regular cervical smear tests. This is because no vaccine is 100 per cent effective and this vaccine will not provide protection against all types of HPV. It also won't protect you from any cancerous changes that may be caused by an HPV infection you may already have without knowing. It is important to keep having regular smear tests.
  • People who have an underactive immune system, for example due to a genetic defect, disease such as HIV infection, or treatment with medicines that suppress the immune system, such as chemotherapy, high-dose corticosteroids, or immunosuppressants, eg used following an organ transplant, may not produce an adequate number of antibodies in response to this vaccine. As a result, the vaccine may be less effective in these people. Ask your doctor for more information and advice if this applies to you.

Not to be used in

  • Sudden feverish illness. (The vaccine should be postponed until after recovery.)
  • This vaccine is not recommended for girls under nine years of age, as its safety and effectiveness have not been studied in this age group.

This vaccine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction after having this vaccine inform your doctor or pharmacist immediately.

Use with caution in

  • People at risk of bleeding after an injection into a muscle, for example due to blood clotting disorders such as haemophilia or a reduced platelet count in the blood (thrombocytopenia).

Pregnancy and breastfeeding

Certain vaccines should not be used during pregnancy or breastfeeding. However, other vaccines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before having any vaccine.

  • As the safety of this vaccine for use during pregnancy has not been fully established, it is recommended that it is not given to pregnant women. Instead it should be postponed until after the pregnancy is over. Seek further advice from your doctor.
  • This vaccine has not been studied in women who are breastfeeding and the possible effect of the vaccine on a nursing infant are not known. The vaccine should only be given to breastfeeding mothers if the potential advantages outweigh any possible risks to the nursing infant.

Side effects

This vaccine contains no live virus and so cannot cause infection with HPV or any of the diseases HPV can cause.

Vaccines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this vaccine. Just because a side effect is stated here does not mean that all people receiving this vaccine will experience that or any side effect.

Very common (affect more than 1 in 10 people)

  • Pain, redness or swelling at the injection site.
  • Headache.
  • Muscle pain (myalgia).
  • Fatigue.

Common (affect between 1 in 10 and 1 in 100 people)

  • Disturbances of the gut, such as nausea and vomiting, diarrhoea, abdominal pain.
  • Skin reactions such as rash, itching or hives.
  • Fever.
  • Joint pain (arthralgia).

Uncommon (affect between 1 in 100 and 1 in 1000 people)

  • Dizziness.
  • Infection of the nose, throat or windpipe.
  • Hard lump or tingling sensation at the injection site.

Unknown frequency (reported since the vaccine has been on the market)

  • Swollen glands.
  • Allergic reactions.
  • Fainting in response to the injection.

The side effects listed above may not include all of the side effects reported by the vaccine's manufacturer. For more information about any other possible risks associated with this vaccine, please read the information provided with the vaccine or consult your doctor or pharmacist.

How can this vaccine affect other medicines or vaccines?

People taking medicines that suppress the activity of the immune system, for example chemotherapy, high-dose corticosteroids, or immunosuppressants used following an organ transplant, may not produce adequate numbers of antibodies in response to this vaccine. As a result, the vaccine may be less effective in these people.

This vaccine can be safely given to women and girls taking oral contraceptives.

This vaccine can be safely given at the same time as booster vaccines against diphtheria, tetanus, pertussis and polio vaccines (eg Infanrix-IPV, Repevax, Revaxis). However, if given at the same time, the vaccines should be given into different sites and preferably separate limbs.

The effect of giving this vaccine at the same time as any other vaccines, or in combination with any other medicines has not been studied. You should let your doctor know if you are taking any medicines, or have recently had any other vaccines, or have recently been given immunoglobulin or other blood products, before you are given this vaccine.

Other HPV vaccines

Gardasil is another brand of human papilloma virus (HPV) vaccine. It contains four types of HPV and is used to prevent genital warts as well as cervical cancer. These two vaccines are not interchangeable. Your three dose vaccine course should be completed with the same brand of HPV vaccine, ie, if you receive a first injection of Cervarix, the next two injections to complete the vaccine course should also be with Cervarix.