The main way to prevent HIV infection is to avoid activities that put you at risk, such as having sex without a condom and sharing needles and other injecting equipment.
If you have HIV you can pass it on to others if you have sex without a condom, or share needles, syringes, or other injecting equipment.
It is important to continue to practise safer sex even if you and your sexual partner both have HIV. This is because you can catch another strain of the virus that your HIV medication may not be able to control.
HIV can be spread by having vaginal or anal sex without a condom. There is also a risk of transmission through oral sex, but this risk is much lower.
HIV can also be caught from sharing sex toys with someone infected with HIV.
See causes of HIV for more on transmission of HIV.
The best way to prevent HIV and other sexually transmitted infections (STIs) is to use a condom for penetrative sex and a dental dam for oral sex.
Condoms come in a variety of shapes, colours, textures, materials and flavours. Both male and female condoms are available.
A condom is the most effective form of protection against HIV and other STIs. It can be used for vaginal and anal sex, and for oral sex performed on men.
HIV can be passed on before ejaculation, through pre-come and vaginal secretions, and from the anus.
It is very important that condoms are put on before any sexual contact occurs between the penis, vagina, mouth or anus.
Lubricant, or lube, is often used to enhance sexual pleasure and safety, by adding moisture to either the vagina or anus during sex.
Lubricant can make sex safer by reducing the risk of vaginal or anal tears caused by dryness or friction, and it can also prevent a condom from tearing.
Only water-based lubricant (such as K-Y Jelly) rather than an oil-based lubricant (such as Vaseline or massage and baby oil) should be used with condoms.
Oil-based lubricants weaken the latex in condoms and can cause them to break or tear.
A dental dam is a small sheet of latex that works as a barrier between the mouth and the vagina or anus to reduce the risk of STIs during oral sex.
Dental dams are available in a variety of flavours and colours, and typically come in two forms:
- a sheet, which can be spread across the vagina or anus and held in place during oral sex by either the giver or the receiver
- a mask with elasticised bands, which is held in place around the ears of the person giving oral sex, leaving the hands free
It is important that dams are only used once, the same side of the dam is always kept against the body, and a new dam is used if a new area of the body is being stimulated. A dam should never be moved from the vagina to the anus or vice versa.
Find out more about what sexual activities can put you at risk of HIV and other STIs.
Sharing needles and injecting equipment
If you inject drugs, don't share needles or syringes, or other injecting equipment such as spoons and swabs, as this could expose you to HIV and other viruses found in the blood, such as hepatitis C.
Many local authorities and pharmacies offer needle exchange programmes, where used needles can be exchanged for clean ones.
If you are a heroin user, consider enrolling in a methadone programme. Methadone can be taken as a liquid, so it reduces your risk of getting HIV.
A GP or drug counsellor should be able to advise you about both needle exchange programmes and methadone programmes.
If you are having a tattoo or piercing, it's important that a clean, sterilised needle is always used.