What is HIV?
HIV stands for human immunodeficiency virus. This virus weakens the immune system by destroying a type of white blood cell known as CD4 that normally protects the body against infection. If left untreated, HIV infection can lead to the development of AIDS.
What is AIDS?
AIDS stands for acquired immunodeficiency syndrome. It is the last stage of HIV infection, occurring when the body's immune system is severely damaged and the CD4 cell count drops below 200 cells/mm3. This gives rise to opportunistic infections, severe illness, and increased susceptibility to certain types of cancer.
Causes of HIV/AIDS
HIV can be contracted through infected blood, sperm, or vaginal fluids in the following ways:
- Through vaginal, anal, or oral sex with an infected partner whose blood, sperm, or vaginal fluids enter your body.
- Sharing contaminated needles and syringes with an infected person
- Through receiving blood transfusions from an infected person
- Mothers who are infected can pass the virus on to their children during pregnancy, childbirth, or breastfeeding.
Symptoms of HIV/AIDS
The symptoms of HIV and AIDS vary, depending on the phase or stage of infection.
- Primary Infection (Acute HIV): Some may develop a flu-like sickness 2-4 weeks after being infected by the virus. Primary (acute) HIV infection is a short-term sickness that can last a few weeks. The signs and symptoms are usually mild and may include:
- Cough
- Night sweats
- Fever
- Headache
- Joint pain
- Skin rash
- Sore throat and painful sores in the mouth
- Swollen lymph glands primarily in the neck
- Diarrhoea
- Weight loss
- Clinical Latent Infection (Chronic HIV): HIV is still present in the body and white blood cells at this stage of infection. Many may not experience any symptoms during this time. This stage can extend for years or may progress to more severe diseases much sooner.
- Symptomatic HIV Infection: As the virus multiplies and destroys your immune cells, you may develop mild infections or chronic signs and symptoms such as:
- Swollen lymph nodes
- Diarrhoea
- Fatigue
- Fever
- Weight loss
- Shingles
- Pneumonia
- AIDS: Progression to the final stage of HIV infection usually takes about 8 to 10 years. Common signs and symptoms during this stage include:
- Recurrent fever and chills
- Persistent fatigue
- Chronic diarrhoea
- Bumps and rashes on the skin
- White spots or lesions on the mouth and tongue
- Opportunistic illnesses such as meningitis, toxoplasmosis, oesophagal candidiasis, pneumocystis pneumonia, and Kaposi's sarcoma
Diagnosis of HIV/AIDS
HIV/AIDS can be detected using blood or saliva tests. The following tests are available:
- Antigen/Antibody Tests: These tests usually involve drawing blood from a vein to detect the presence of HIV antigens which develop within a few weeks of HIV contact.
- Antibody Tests: These tests are used to identify antibodies to HIV in blood or saliva. The majority of the rapid HIV tests, including at-home self-tests, are antibody tests. Antibody testing can take 3 to 12 weeks to become positive after exposure to the virus.
- Nucleic Acid Tests (NATs): These tests check for the virus itself in your bloodstream (viral load). They also require the drawing of blood from a vein. Your doctor may recommend NAT if you have been exposed to HIV in the last few weeks.
Several tests can help your doctor assess the stage of your condition and the appropriate treatment for you if you've been diagnosed with HIV/AIDS, including:
- CD4 T-Cell Count: This test measures the number of CD4 cells in your blood. When your CD4 T-cell count falls below 200 cell/mm3, HIV infection advances to AIDS, even if no symptoms are present.
- Viral Load (HIV RNA): This test determines how much virus is present in your blood. The goal after starting HIV treatment is to have a viral load that is undetectable. This lowers your risk of opportunistic infection and other HIV-related problems dramatically.
- Drug Resistance: Some HIV strains are resistant to medications. This test helps your doctor to determine the right medication to treat your particular strain of the virus.
Treatment for HIV/AIDS
There is currently no cure for HIV/AIDS. Your body will not be able to rid itself of the infection once acquired. Fortunately, there are a variety of drugs that can help to control HIV and prevent problems. These medications are collectively known as antiretroviral therapy (ART).
ART is often a combination of three or more drugs from several drug classes. This method provides the best probability of reducing HIV levels in the blood. Typically, two medications from one class are combined with a third drug from a different class.
The classes of anti-HIV drugs include:
- NNRTIs (non-nucleoside reverse transcriptase inhibitors), which block a protein that HIV uses to replicate itself.
- NRTIs (nucleoside or nucleotide reverse transcriptase inhibitors), which are defective versions of the building blocks required for HIV replication.
- Protease inhibitors (PIs), which block the action of HIV protease, another enzyme required for HIV replication.
- Integrase inhibitors, which stop HIV from inserting its genetic material into CD4 T-cells by blocking the effects of an enzyme called integrase.
- HIV entrance or fusion inhibitors, which prevent HIV from infecting CD4 T-cells.
Prevention
There is no curative treatment for AIDS and no vaccination to prevent HIV infection. But you can protect yourself and others from infection in the following ways:
- Practice safe sex such as using condoms and avoiding risky sexual behaviour
- Avoid sharing needles
- If you have HIV, taking antiretroviral medication can prevent your partner from contracting the infection.
- If you have a high risk of getting HIV, daily PrEP (pre-exposure prophylaxis) medication may help to reduce the risk.
- If you've been exposed to HIV, you should take post-exposure prophylaxis (PEP) medications within 72 hours of exposure.