Updated 15 January 2018

What is HIV/Aids?

HIV attacks and gradually destroys the immune system, which protects the body against infections. Acquired Immune Deficiency Syndrome (Aids) is caused by infection with the Human Immunodeficiency Virus (HIV).


Alternative names: Human Immunodeficiency Virus, Acquired Immune Deficiency Syndrome

HIV/Aids is caused by the Human Immunodeficiency Virus (HIV). The virus is mainly transmitted through sexual intercourse, but can also be passed down from mother to child during pregnancy, or acquired via blood transfusion with infected blood, the sharing of needles (e.g. during drug use) or through needle-stick injuries (if you’re a healthcare worker, for example).

Once you’re infected, the virus remains in your body for life. Although there currently isn’t a cure for HIV, antiretroviral treatment (ART) helps to keep the virus under control and enables people living with HIV to lead a full, productive life. In addition, we now also know that ART prevents the onward transmission of HIV.

Acquired Immune Deficiency Syndrome (Aids) is a chronic, life-threatening disease caused by the HI virus. The virus attacks and gradually destroys the immune system, which defends the body to against infection and disease. Without treatment, people with HIV become susceptible to a variety of opportunistic infections – so called because they take advantage of the body's weakened immune system. These infections are unlikely to occur in people with healthy immune systems.

Aids develops during the final stages of HIV infection. Strictly speaking, Aids isn’t a specific illness but a collection of many different conditions that manifest in the body (or in specific parts of the body) because the HI virus has weakened the immune system to such an extent that it can no longer fight disease.

It may take years for the immune system to deteriorate to such an extent that someone living with HIV becomes ill and is diagnosed with Aids. During this time, they may look and feel perfectly well. This explains why so many people are unaware that they’re infected with HIV. But even though they feel healthy, they can still transmit the virus to others.

The exact origin of the HI virus has been a topic of much debate over the past few decades. We now know that at some point in the 1970s, the virus began spreading across the globe, although it first came to the attention of medical authorities and researchers in the early 1980s. The virus was, however, born much earlier.

Recognition of the virus in the 1980s marked the beginning of the epidemic as we know it today. In South Africa, the epidemic started to explode in the early 1990s and, by the year 2000, more than 20% of the population had been infected. 

Who gets HIV/Aids?

HIV/Aids is one of the world's most serious health threats, and South Africa remains the country with the highest number of people living with HIV in the world. With over seven million South Africans (18.9% of the adult population) currently infected, stemming the HIV/Aids epidemic in this country remains an ongoing challenge.

In 2016, an estimated 36.7 million people were living with HIV across the globe. According to UNAIDS, 1.8 million people became newly infected with HIV in 2016 while 1 million people died from Aids-related illnesses in the same year. Approximately two-thirds of new cases occurred in sub-Saharan Africa. Other regions significantly affected by HIV/Aids include Asia and the Pacific, Latin America and the Caribbean, as well as Eastern Europe and Central Asia.

Worldwide, most infections are transmitted between heterosexual partners. In some countries, men who have sex with men, injecting drug users, sex workers, transgender people and prisoners are disproportionally affected by HIV. People with sexually transmitted infections (STIs) are also far more vulnerable than others to becoming infected with HIV. Sores on the genitals can, for example, create an entry point for the virus.

HIV primarily affects people in their most productive years, with a third of new infections occurring among people between the ages of 15 and 24. In South Africa, HIV prevalence among pregnant women has hovered around 30%, but reaches towards 50% in some provinces. KwaZulu-Natal has the highest number of people living with HIV, followed by Mpumalanga, Gauteng and the Free State. The Western and Northern Cape provinces have the lowest prevalence rates.

The good news is that much progress has been made in terms of managing the pandemic – a result of effective funding and prevention programmes. Thanks to improved access to antiretroviral treatment (ART), Aids mortality has decreased significantly in South Africa over the last few years, while life expectancy has increased.

Myths about HIV/Aids

Unfortunately, many HIV/Aids myths are still circulating. It’s important to realise that you CANNOT get infected through:

  • Mosquito and other insects bites 
  • Urine or sweat 
  • Public toilets, saunas, showers or swimming pools 
  • Sharing towels, linen or clothing
  • Going to school with, socialising or working with HIV-positive people 
  • Sharing cutlery or crockery 
  • Sneezes or coughs 
  • Touching, hugging, shaking hands with or dry kissing a person with HIV 
  • (Sexual) contact with animals (HIV is strictly a human virus and isn’t carried by animals)


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HIV/Aids expert

Dr Sindisiwe van Zyl qualified at the University of Pretoria in 2005. She is a patients' rights activist and loves using social media to teach about HIV. She is in private practice in Johannesburg.

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