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What are HIV and AIDS?

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HIV and AIDS are different but connected. HIV is a virus that can get into our bodies and start to make us sick over a period of time. AIDS is a set of symptoms and illnesses that develop at the final stage of HIV infection. 

HIV can become AIDS if it is not treated. But treatment means you can stay healthy and live a long life without getting AIDS. 

What does HIV stand for? What is it?

Human immunodeficiency virus. HIV is a virus that attacks cells in our immune system (our body’s natural defence against illness). 

How can you get HIV?

HIV can be passed on through: 

  • unprotected sex (without a condom) 

  • sharing needles or syringes that have been used to inject drugs 

  • contaminated blood transfusions and organ transplants 

  • pregnancy, birth or breastfeeding. 

How can you stop HIV being passed on?

If you have sex:  

  • take PEP after you might have been exposed to HIV 

  • get medically circumcised if you have a penis to reduce your risk. 

If you inject drugs: 

  • always use a clean needle and syringe 

  • never share injecting equipment. 

If you’re pregnant and have HIV: 

  • take treatment during pregnancy and breastfeeding. This will stop HIV passing to your baby. 

How to protect yourself from HIV

How do I know if I have HIV?

The only way to know if you have HIV is to take an HIV test. This will confirm your HIV status (whether you are HIV-positive or HIV-negative).  

HIV testing

What if I get HIV?

If you get HIV, visit a healthcare provider so that you can get antiretroviral treatment (ART) straight away. It is very effective and people with HIV can enjoy a long and healthy life. 

HIV treatment

Can I get rid of HIV?

Unfortunately, there is no way to get rid of (cure) HIV. But the treatment is very effective. It can reduce the level of HIV in your body to such low levels that blood tests cannot detect it. This is also called being 'undetectable’. Having an undetectable viral load means you cannot pass on HIV to other people. 


What does AIDS stand for? What is it?

Acquired immune deficiency syndrome. It is also called advanced HIV infection or late-stage HIV. AIDS is a set of symptoms and illnesses that develop when an advanced HIV infection has destroyed the immune system. If left untreated it will lead to death. 

How can you get AIDS?

AIDS is caused by the HIV virus. It is the last stage of HIV, when the infection is very advanced. 

How can you stop getting AIDS?

By taking treatment for HIV correctly. Remember to take it at the same time every day and don’t miss any doses. 

How do I know if I have AIDS?

AIDS is when your immune system is too weak to fight off infection. You will develop certain symptoms and illnesses (known as ‘opportunistic infections’). It is also diagnosed when the level of immune system cells in your body drops too low (below 200 CD4 cells/mm). 

What if I get AIDS?

If you are diagnosed with AIDS, it is important that you take antiretroviral treatment as soon as possible. Many people’s immune systems recover very well, and they become healthy again. If you have an opportunistic infection, you can take treatment for that too. 

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What type of virus is HIV?

HIV is a retrovirus. More specifically, it is a lentivirus which are viruses that cause disease slowly. 

What does HIV look like?

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HIV is a spherical virus. It is made up of: 

  • The envelope – this is the outer shell which is covered in spikes of glycoproteins 

  • The glycoproteins - these spikes allow HIV to lock onto the CD4 receptors on CD4 cells (in our immune systems) and enter them 

  • The matrix – this is a layer inside the envelope that contains the capsid 

  • The capsid – this is a cone-shaped structure in the centre of the virus which contains the core of the virus, or nucleus 

  • The enzymes and RNA – inside the capsid are two enzymes that HIV needs to replicate (the reverse transcriptase and integrase molecules) and two strands of RNA (where it stores its genetic information). 

How does HIV store its genetic information?

Unlike other viruses, HIV stores its genetic information using RNA instead of DNA. HIV’s RNA is made up of nine genes which contain the instructions to make new viruses. When HIV enters a human cell, it will ‘make’ DNA so it can make copies of itself. 

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Next: How HIV infects the body

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