theTeacher and BroadReach Healthcare explain key facts about the HI virus in the second part of a series
How is HIV spread?
HIV is spread through the exchange of bodily fluids between people. The main ones are blood, semen, vaginal fluid and breast milk.
HIV can’t live for long outside the body so to become infected the body fluid from an infected person must come into contact with your body.
The most common ways to become infected with HIV are:
- Having unprotected sex with an infected partner;
- Injecting drugs using a needle or syringe that has been used by someone who is infected;
- Through mother-to-child transmission during pregnancy, child birth and breastfeeding.
How is HIV passed on?
If you or your partner or both of you are infected with HIV, then it can be spread through:
Sexual fluids
- Vaginal sex: HIV is in the sexual fluids of an infected person. For a woman, it means HIV is in the vaginal fluids, which are produced by the vagina to keep it clean and to help make intercourse easier. In a man, it is in his semen. If a man with HIV has vaginal intercourse without a condom, then HIV in the infected fluid can pass into the woman’s bloodstream through the walls of the vagina. The risk of HIV transmission is increased if the woman has a cut or sore inside or around her vagina. This makes it easier for the infected fluid to enter her bloodstream.
If a woman with HIV has sexual intercourse without a condom, HIV could get into the man’s blood through a sore on his penis or by getting into his urethra (the tube that runs down the penis) or underneath his foreskin.
If there is any contact with blood during sex, this increases the risk of infection — for example, if intercourse occurs during a woman’s period.
“Dry sex” is a sexual practice in which women use substances such as herbs, powders, lemon juice, snuff or newspapers to tighten and dry their vaginas before sex, because it is believed to give more pleasure to the man. This activity is unsafe and dry sex will make a woman more prone to becoming infected with HIV because it is likely to cause small cuts and tears in her vagina.
- Anal sex: If a couple has unprotected anal sex, the risk of HIV infection is greater than with vaginal sex. The lining of the anus is more delicate than the vagina, so it’s more likely to be damaged during intercourse and any contact with blood during sex increases the risk of infection.
Anal sex is also generally drier than vaginal sex and may result in more tearing of the skin, allowing the HIV to pass from one person to the other.
- Oral sex: Oral sex with an infected partner carries a small risk of HIV infection. If a person gives oral sex to a man with HIV, then infected fluid could get into the mouth. If the person has bleeding gums or tiny sores or ulcers somewhere in the mouth, there is a risk of HIV in the infected fluid entering the bloodstream.
The same is true if infected sexual fluids from a woman get into the mouth of her partner.
There is also a small risk if a person with HIV gives oral sex when they have bleeding gums or a bleeding wound in their mouth. HIV infection through oral sex alone seems to be very rare, and there are things you can do to protect yourself.
Blood
- Injecting drugs: Sharing injecting equipment such as needles is very risky as it is one of the easiest ways to become infected with HIV. If you share a needle with a person who is infected with HIV, it is likely that some of their infected blood will be in or on the needle. When you inject this needle into your body, it’s not just the drugs that will enter your bloodstream, but the HIV as well.
- Blood transfusions: These days, in most countries all the blood used for transfusions is tested for HIV. In those countries where the blood has been tested, HIV infection through blood transfusions is now extremely rare.
- Tattoos, piercing and cutting: Anything that potentially allows another person’s bodily fluids to get into your bloodstream carries a risk. If the equipment has not been sterilised before having a tattoo, piercing or cutting, there could be a risk of exposure if the person it was used on before was HIV-positive. Sometimes in traditional tattooing, blades are used and if these are not properly sterilised or if a new blade is not used there is a risk of HIV transmission. Similarly, in some traditional health practices making cuts on the body with sharp instruments is commonplace. If these sharp instruments have not been sterilised between use, then there is a risk of HIV transmission.
Breast milk and mother-to-child transmission
An infected pregnant woman can pass HIV to her unborn baby either before or during birth. HIV can also be passed on during breastfeeding. If a woman knows that she is infected with HIV, there are drugs that she can take to reduce the chances of her child becoming infected.
How does HIV transmission work?
Most transmission occurs when an individual has just been infected with HIV and is unaware of their status. During this phase, the HIV levels in the bodily fluids and the risk of transmission are very high.
For HIV to be spread from one person to another, four factors need to be present:
- Entry point: This is where the HIV will enter the body. HIV can enter the body if there is a break or tear in the skin or through the vagina and the penis.
- Exit point: This is the point at which HIV leaves the infected person’s body and enters the uninfected person.
- Activity: HIV can be transmitted through various activities. These include unprotected sexual intercourse, injecting drugs and breastfeeding.
Infected fluid: For HIV to be transmitted from one person to another, the virus needs to be present in bodily fluids.
It is not possible to become infected with HIV by sharing crockery or cutlery, touching, hugging or shaking hands, or from sweat, urine, mucous, tears or toilet seats.