Sexually transmitted infections (STIs) are infections that are passed from one person to another through unprotected sex or genital contact.
STIs are so common that anyone who has ever had sex could get one. Whether you get one is not about you being good, bad, clean or dirty, but it’s about being normal and sexually active. You can reduce your chances of getting an STI by using condoms (pukoro ure) with all new partners and having regular sexual health checks.
There are many different types of STIs. Read more about the most common STIs.
How safe is sex?
Any sexual activity exposes you or your partner to STIs. The risks of getting STIs vary with different sexual activities.
Kissing exposes you and your partner to a few STIs such as herpes and hepatitis. Avoid kissing when sores or cuts are present in and around your mouth.
Fingering is when someone inserts one or more fingers into their partner's vagina or anus. It's not common for fingering to spread STIs, but there are still risks. If there are any cuts or sores on your fingers, no matter how small, the risk of passing on or getting HIV or other blood-borne infections such as hepatitis B or hepatitis C increases. You can lower your risk by wearing surgical gloves.
Skin-to-skin touching exposes you and your partner to several STIs such as syphilis, genital herpes, HPV, pubic lice and scabies.
Oral sex exposes you and your partner to many STIs. Giving and getting oral sex puts you at risk of getting chlamydia, gonorrhoea, syphilis, genital herpes, hepatitis B and HIV.
Vaginal sex exposes you and your partner to all the STIs.
Anal sex exposes you and your partner to most of the STIs, such as chlamydia, gonorrhoea, syphilis, genital herpes, HPV, hepatitis B, HIV, pubic lice and scabies.
Sex toys – any object used in sex can be called a sex toy, whether it's designed for this use or not. It's important to keep sex toys clean. If you're sharing sex toys, make sure you wash them between each use and always use a new condom each time. Sharing sex toys has risks, including getting and passing on infections such as chlamydia, syphilis and herpes. If there are any cuts or sores around your vagina, anus or penis and there's blood, there's an increased risk of passing on hepatitis B, hepatitis C and HIV.
If you choose to have vaginal, oral or anal sex, always use condoms. They reduce the risk of spreading STIs.
Sexual health self-assessment
How much do you know about having a safer sex life? Take the safer sex test and find out how much you know about contraception and sexually transmitted infections.
What are the risk factors for STIs?
Anyone who has sex or engages in sexual activity is at risk of getting an STI, but you are at higher risk of getting STIs if:
you have more than one sexual partner
your partner has or has had more than one sexual partner
you have sex with someone who has an STI
you've had STIs in the past.
Exposure to infected needles and syringes, by you or your partner using intravenous drugs (injected into a vein), or through tattooing or piercing equipment, can also put you at risk of getting STIs such as hepatitis B and HIV.
Adolescents have a higher risk of getting an STI than adults.
What are the risks of not treating an STI?
STIs will not go away by themselves so if you get one you need to get it treated. If left untreated some STIs can be a serious health risk and can cause other conditions such as:
pain and inflammation in your genital area
pelvic inflammatory disease (PID) in women and epididymitis in men
cancers of your reproductive system.
What if I am pregnant and have an STI?
Having an STI during pregnancy can harm your baby. Gonorrhea and chlamydia both can cause health problems in the infant ranging from eye infections to pneumonia. Syphilis may cause miscarriage or stillbirth. HIV infection can occur in a baby.
If you are pregnant and you or your partner have had – or may have – an STI, it's important to tell your healthcare provider. Your baby may be at risk. Tests for some STIs are offered routinely during prenatal care. It is best to treat the STI early to decrease the chances that your baby also will contract the infection. You and your partner both may have to be treated.
What are the symptoms of STI?
Not all STIs have symptoms, and it is possible to have an STI without even knowing as sometimes the symptoms are so small, especially in the early stages. Because there are many different STIs, the symptoms may vary. Some of the general symptoms include:
unusual discharge from your penis or vagina
itch or rash on or around your genitals
lumps, blisters or sores on or around your genitals
pain in your genital area or groin
pain in your penis or vagina when having sexual intercourse
pain or a burning sensation when passing urine (peeing).
How to get tested for an STI?
You can be tested for STIs at a sexual health clinic, family planning clinic or at your GP surgery. You should get tested:
if you or your partner have any symptoms
if the condom breaks or if you have sex without one
before you have sex with a new partner
if you or your partner have been sexually active and have not been tested
if you know your current or past partner has or has had an STI
if you or your partner have shared needles for drugs, tattooing or piercing.
Telling your partner
If you have an STI, it is important to tell your partner, so they can be tested and treated as well. This reduces the spread of the STI and lessens your chance of getting it. It's best to tell your partner as soon as possible after finding out that you have an STI, or before having sex with an untreated partner. Some people may find the experience of telling their partner awkward and difficult. If so, talk to your doctor or nurse, or contact your local sexual health clinic, or family planning clinic for guidance.
There are many different STIs. The following is a brief description of the most common ones. Click on the links below for more detailed information.
Chlamydia is the most commonly diagnosed STI in New Zealand. It affects both men and women. Most people who have chlamydia don't show any symptoms – but they can still infect other people. Chlamydia can be easily treated with antibiotics. Left untreated, chlamydia can cause infertility.
Gonorrhoea is very common in people aged under 25 years. About 50% of women and 10% of men don't experience any symptoms and don't know they're infected. In women, gonorrhoea can cause pain or a burning sensation when urinating (peeing), a vaginal discharge (often watery, yellow or green), pain in your lower abdomen (tummy) during or after sex, and bleeding during or after sex or between periods, sometimes causing heavy periods.
In men, gonorrhoea can cause pain or a burning sensation when urinating (peeing), a white, yellow or green discharge from the tip of your penis, and pain or tenderness in your testicles. It's also possible to have a gonorrhoea infection in your rectum, throat or eyes.
Syphilis enters your body through tiny breaks in your skin, mainly in your genital area or mouth. Many people do not get any symptoms and would not know they had syphilis without having a blood test. Treatment is normally with injections of an antibiotic called penicillin. If left untreated, the syphilis bacteria eventually causes damage to your internal organs. People without symptoms can still develop these problems later if their syphilis is not treated.
Both men and women get trichomoniasis, but it is more common in women. In women, the infection can cause a frothy yellow or watery vaginal discharge that has an unpleasant smell, soreness or itching around your vagina, and pain when passing urine (peeing).
In men, trichomoniasis rarely causes symptoms. You may experience pain or burning after passing urine (peeing), a whitish discharge, or an inflamed foreskin.
Genital warts are caused by the human papilloma virus (HPV). They appear as small fleshy growths, bumps or skin changes, on or around your genital or anal area. The warts are usually painless, but you may notice some itching or redness. Sometimes, they can cause bleeding. You don't need to have penetrative sex to pass the infection on because HPV is spread by skin-to-skin contact. Several treatments are available for genital warts, including creams and freezing the warts (cryotherapy).
Genital herpes is caused by a virus known as the herpes simplex virus (HSV).The symptoms of genital herpes are similar to cold sores found on your mouth, except they appear on your genital skin. Small, painful blisters or sores usually develop, which may cause itching or tingling, or make it painful to urinate (pee). After you've been infected, the virus can remain dormant (inactive) and certain triggers can reactivate the virus, causing the blisters to develop. Most people with genital herpes don’t have any symptoms and the virus can be passed on by people with no symptoms. Genital herpes cannot be cured; however, symptoms can be treated.
Hepatitis B is a viral infection that causes inflammation of your liver. Some people do not have any symptoms, but others can have symptoms such as feeling sick or vomiting lack of appetite, flu-like symptoms (such as tiredness, general aches and pains or headaches), abdominal (tummy) pain, clay-coloured bowel motions and/or dark-coloured urine and yellowing of your skin and eyes (known as jaundice). One of the most effective ways to avoid getting hepatitis B is get immunised with the hepatitis B vaccine.
HIV is caused by the human immunodeficiency virus which causes damage to your body's immune system and impairs your ability to fight disease-causing organisms. HIV is most commonly passed on through unprotected sex. Without treatment, some people with HIV may develop the potentially life-threatening condition known as acquired immunodeficiency syndrome (AIDS). There's no cure for HIV, but there are treatments that allow most people to live a long and otherwise healthy life.
Pubic lice, also called crabs, are usually found in pubic hair but can live in your underarm hair, body hair, beards and sometimes eyebrows or eyelashes. They are easily passed to others through close genital contact. The lice crawl from hair to hair but don't jump or fly from person to person. It may take several weeks for you to notice any symptoms. Most people experience itching, and you may notice the lice or eggs on your hairs. Pubic lice are treated with special creams, lotions or shampoos available from your pharmacy or your GP. You don't need to shave off your pubic hair or body hair.
Information for health professionals
The information on this page will be of most interest to clinicians (doctors, nurses, specialists, etc) and those interested in more detail.