Human Immunodeficiency Virus (HIV), the causative agent of AIDS.
The Human Immunodeficiency Virus, more commonly known as HIV, is a member of the lentivirus sub-set of the retrovirus family of pathogens. It causes AIDS, or Acquired Immuno Deficiency Syndrome a condition wherin the gradual failure of the immune system causesd by the HIV pathogen allows diseases and cancers, with the potential to threaten life in humans, to thrive.
The progressive breakdown of the immune system is caused by the infection of vital cells within the human body, for example helper T-cells, macrophages and dendritic cells. This increases the chance for opportunistic infections to take hold. There is no cure for HIV, but there are treatments to enable most people with the virus to live a long and healthy life. For further information on symptoms of HIV/AIDS review research - more.
The human immunodeficiency virus (HIV) infection has become a pandemic with more than 40 million infected people worldwide. The virus attacks the immune system of the host thus exposing them to opportunistic infections in various systems of the body. The use of highly active anti-retroviral therapy (HAART) has converted a previously lethal condition to a chronic condition with relatively benign cause. This has allowed infected patients to live longer than before.
HIV is found in the body fluids of an infected person, which includes semen and vaginal fluids, blood, inside the anus and breast milk.
HIV cannot be transmitted by saliva alone. But the saliva of a person with HIV can be infectious if it contains blood or other body fluids.
The most common way of getting HIV in the UK is by unprotected sexual contact with a person who has HIV. This can include vaginal, anal and oral sex. According to statistics from the Health Protection Agency, 95% of those diagnosed with HIV in the UK in 2010 acquired HIV as a result of sexual contact.
Other ways of getting HIV include - using a contaminated needle, syringe or other injecting equipment to inject drugs, tranmission from mother to baby, before or during birth, or by breastfeeding
The only way to find out if you have HIV is to have an HIV test.
If you think you might be at risk of HIV, you should have a test immediately. The earlier HIV is detected, the more likely it is that treatment will be successful.
Emergency anti-HIV medication called PEP (post-exposure prophylaxis) may stop you becoming infected, but treatment must be started within three days of coming into contact with the virus.
It can take several weeks after infection before the virus is picked up in testing, so after your initial test you will be advised to have another one a few weeks later.
There are a number of places you can get an HIV test, including your GP surgery and sexual health clinics and clinics run by the Terrence Higgins Trust.
If your test is positive you will be referred to a specialist HIV clinic where you'll have more blood tests to show what effect HIV is having on your immune system and be able to discuss treatment options.
The method for testing for HIV-1 is as follows:
Use of an enzyme-linked immunosorbent assay (ELISA) which detects antibodies used to fight HIV-1.
If there is no reaction to the ELISA the specimin is considered to be HIV-negative unless they have been exposed to a partner of unknown or positive HIV status.
Those with reactive samples and re-tested and re-tested again. If either sample is found to be reactive to the ELISA then they are sent for additional testing, for example Western Blot Testing.
Those whose samples repeatedly show reactivity with ELISA and with the additional testing are considered to be HIV positive.
The accuracy of this testing method is very high, in excess of 99%
Living with HIV
Although there is no cure for HIV, treatments are much more successful than they used to be, enabling people with HIV to lead as normal a life as possible.
Medication, known as antiretrovirals, works by slowing down the damage the virus does to the immune system. These medicines come in the form of tablets, which need to be taken every day.
You will be encouraged to take regular exercise, eat a healthy diet, stop smoking and have yearly flu jabs and five-yearly pneumococcal vaccinations to minimise the risk of getting serious illnesses.
Someone with HIV is said to have AIDS when investigations show their immune system has stopped working and they develop life-threatening illnesses such as cancer.
HIV can affect anybody.
The best way to prevent HIV is to practise safer sex and use a condom. If you inject drugs, do not share needles, syringes or other injecting equipment such as spoons and swabs.
How common is HIV?
At the end of 2010, an estimated 91,500 people in the UK were living with HIV. Of these, around one in four (22,000 in total) did not know they were infected.
That total includes an estimated 40,100 gay men, and an estimated 47,000 heterosexual men and women.
HIV disease continues to be a serious health issue for parts of the world. Worldwide, there were about 2.5 million new cases of HIV in 2011. About 34.2 million people are living with HIV around the world. In 2010, there were about 1.8 million deaths in persons with AIDS, and nearly 30 million people with AIDS have died worldwide since the epidemic began.
Sub-Saharan Africa bears the biggest burden of HIV/AIDS, countries I South and Southeast Asia, Eastern Europe and Central Asia, and those in Latin America are significantly affected by HIV and AIDS.