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HIV is a virus: the Human Immunodeficiency Virus. Actually, it’s a retrovirus – retroviruses like HIV cannot reproduce on their own – they need to infect the cells of another living organism in order to make copies of themselves. For many viruses, the human immune system can find them and deal with them fairly quickly. HIV, though, is different – it attacks the cells of the human immune system itself, taking them over and turning them into “factories” to produce more HIV cells, before destroying the host cell. Over time, more and more HIV cells are produced, and the human immune system is weakened and ultimately (if untreated) destroyed, leaving the person open to a wide range of infections – often called “opportunistic infections” or OIs. It is often such an OI that will lead to the death of the infected person.
The two are not the same at all. As we have seen, HIV is a virus. AIDS, in the other hand, stands for Acquired Immune Deficiency Syndrome. This is the term that is used to describe the late stage of HIV infection, when the human immune system has stopped working, and the person develops one or more OIs. Many HIV specialists now prefer to talk about advanced or late-stage HIV infection, rather than AIDS. Thanks to recent advances in the treatment of HIV, late-stage HIV (or AIDS) is now rarely seen in the UK, though sadly, it is still seen a lot where there is no access to HIV treatment.
HIV is found in the blood and the sexual fluids of an infected person, and in the breast milk of an infected woman. HIV transmission only occurs when a sufficient quantity of these fluids get into someone else’s bloodstream. The body fluids that contain enough HIV to infect someone are:
- seminal fluid
- vaginal fluids, including menstrual fluids
- breast milk
- the mucous found in the rectum
- pre-cum (the fluid that the penis produces for lubrication before ejaculation)
Other body fluids, like saliva, sweat or urine, do not contain enough of the virus to infect another person.
There are various ways a person can become infected with HIV:
- Unprotected sexual intercourse with an infected person: sexual intercourse (vaginal or anal) without a condom carries the risk of HIV infection.
- Contact with an infected person’s blood: if sufficient blood from somebody who has HIV enters someone else’s bloodstream, then HIV can be passed on.
- Use of infected blood products: many people in the past have been infected with HIV by the use of blood transfusions and blood products which were contaminated with the virus. In much of the world this is no longer a significant risk, as blood donations are routinely tested for HIV.
- Injecting drugs: HIV can be passed on when injecting equipment that has been used by an infected person is then used by someone else. In many parts of the world, often because it is illegal to possess them, injecting equipment or works are shared.
- From mother to child: HIV can be transmitted from an infected woman to her baby during pregnancy, delivery and breastfeeding.
People who take ART daily as prescribed and achieve and maintain an undetectable viral load have effectively no risk of sexually transmitting the virus to an HIV-negative partner. This is often referred to as U=U…Undetectable equals Untransmittable.
The full U=U consensus statement can be read here.
The science behind this is clear and unequivocal. U=U has been endorsed by the world’s leading medical and HIV organisations, including BHIVA, NAM, THT, US CDC and many more. For more information, read the i-Base summary here.
HIV is not passed on through normal social contact, including:
- through unbroken, healthy skin
- sharing cups, plates, cutlery or linen, such as towels
- using the same toilets and swimming pools.
Caring for someone living with HIV or AIDS does not put you at risk, and neither does mouth-to-mouth resuscitation. And you can’t breathe it in or get infected by mosquitoes or other animals.
The initial stage of HIV is known as primary HIV infection or seroconversion. Many people develop symptoms, although they might not recognise them at the time, since the symptoms are typically mild, last a short time and easily mistaken for other things. Symptoms usually occur two to six weeks after infection with HIV. Symptoms of primary HIV infection include:
- sore throat
- joint pain
- muscle pain
- swollen glands (nodes)
- a blotchy rash
These early symptoms are often very mild, so it is easy to mistake them for another condition, such as a cold, flu or glandular fever. After the initial symptoms have gone, typically after a few days, there may not be any further symptoms for many years. This is known as asymptomatic HIV infection. During this time, the virus is reproducing in the body and damaging your immune system. Left untreated, HIV will damage the immune system so much that one or more serious, life-threatening conditions will arise. It typically takes about 10 years for the virus to damage the immune system in this way.
Possible symptoms of a serious infection caused by a damaged immune system include:
- persistent tiredness
- night sweats
- unexplained weight loss
- persistent diarrhoea
- blurred vision
- white spots on your tongue or mouth
- dry cough
- shortness of breath
- a fever of above 37C (100F) that lasts a number of weeks
- swollen glands that last for more than three months
AIDS-related illnesses, such as TB, pneumonia and some cancers, may appear. Many of these, though serious, can be treated and most are likely to improve dramatically if HIV treatment is started, since this leads to an improvement in the body’s immune system.