The ways HIV spreads between people. We consider the risks of different sexual practices and ways of practising safer sex to reduce the risk of transmission.
How is HIV transmitted?
HIV is transmitted through ‘bodily fluids’, mainly blood and semen. Tiny traces of the virus have been found in tears and saliva, but there is no known case of this having been a means of transmission. HIV is not found in vomit, sweat or urine.
HIV can be spread when intravenous drug users share needles. The most common way it is spread is through sex.
Both vaginal and anal sex can lead to HIV being transmitted from one person to another. Anal sex is most risky, because the lining of the rectum is easily torn and the rectum is designed to absorb fluid. There is also a high concentration of white blood cells here, which the HIV targets.
You can contract HIV whether you are the active or recipient partner when having sex. If you are the active, penetrating partner, the virus can pass through tiny cuts or abrasions on your penis or through the urethra (through which urine and semen pass).
The virus can be transmitted even if one partner does not ejaculate in the other – since it is present in pre-cum.
Using lots of additional sexual lubricant may also lower the risk, but the risk remains highly significant.
HIV and oral sex
The risk of contracting HIV from giving oral sex is lower – and lower still if your partner doesn’t ejaculate in your mouth. Your saliva will help to inhibit infection – and if you swallow your stomach acids will destroy it.
However, there is a risk. It may be that your mouth has cuts or ulcers, that you have bleeding gums or that you have weakened the lining of your mouth by chewing on it. It is particularly advisable not to brush your teeth before giving oral sex.
There is almost certainly no risk from receiving oral sex.
If you are having sex outside of an absolutely trustworthy, one-on-one relationship in which you have both been tested, the best way to reduce the risk of HIV transmission is to use a condom.
Quite simply, this prevents one person’s blood, semen and other bodily fluids coming into contact with the other’s blood.
This is not absolutely safe sex. It is certainly safer sex.
The main risk is that the condom will break. To help avoid this:
· Use additional lubrication to reduce the level of the friction on the condom.
· Never use two condoms – this will increase the risk of their both breaking.
· Check to see that the condom remains intact.
· Check the sell-by-date on the condom wrapper.
· Never bring the condom into contact with oil, which will degrade the latex. Only use water or silicone based lubricant.
If a condom does break and you fear you may have been exposed to HIV, you should seek post-exposure prophylactic treatment. See your GP or go to hospital as soon as possible, certainly within 72 hours.