What is HIV?
Human immunodeficiency virus (HIV) is the virus that causes acquired immunodeficiency syndrome (AIDS). HIV infects vital cells in the immune system such as CD4+ T cells, macrophages and dendritic cells. The disease severely weakens the immune system and the body’s ability to fight off infections. HIV is spread through bodily fluids.
How HIV is transmitted
Transmission can occur in multiple ways including:
- Sex, including anal, oral and vaginal
- Sharing needles or syringes, rinse water or other equipment that includes bodily fluids
- From mother to child during pregnancy, birth or breastfeeding
- Contact between wounds, broken skin or mucus membranes
HIV cannot be transmitted by saliva, tears or sweat, mosquitoes, ticks or other insects. It also can't be transmitted through skin-to-skin contact such as kissing or other sexual contact that does not involve the exchange of body fluids.
Testing for HIV
The only way to get a certain diagnosis for HIV is through testing. There are three broad types of tests available:
- Antibody tests: These tests make up the majority of HIV tests. Your immune system produces antibodies when you’re exposed to viruses. HIV antibody tests look for these antibodies in your blood or saliva. It takes three to 12 weeks for a patient’s body to make enough antibodies for the test to detect an infection. This is called the window period. If the results are negative, you should be re-tested three months after the possible exposure period.
- Combination (fourth-generation) test: This test, done by taking an oral swab, provides fast results (approximately in 20 minutes). If you’re infected with HIV, an antigen called p24 is produced before the HIV antibodies develop. It can take two to six weeks for a patient’s body to make enough antigens and antibodies for a combination or fourth-generation test to detect HIV. This is called the window period. If the results come back negative, the patient should be re-tested three months after the possible exposure period.
- Nucleic acid test (NAT): The NAT test looks specifically for the virus itself in the blood, as opposed to the antibodies to the virus. This test can either give a positive or negative result, or reveal how much of the virus is present in the bloodstream (known as a viral load test). This test is very expensive and not routinely used unless they have had recent, high-risk exposure or possible exposure with early symptoms of infection.
Stages of HIV
HIV infection comes in three stages:
- Acute infection or seroconversion (normally happens within two to six weeks after exposure). During this time, the body experiences many flu-like symptoms that can include headache; diarrhea; nausea and vomiting; fatigue; aching muscles; sore throat; fever and rash.
- The second stage is called the asymptomatic, or latent period. In this stage, the immune system loses the battle with HIV and the symptoms go away. This period of time can last 10 or more years. This is the period of time that the virus kills off the immune system, making people vulnerable to contract infections and AIDS.
- The third stage is the advanced stage, when the immune system is severely compromised and the patient is often diagnosed with AIDS.
HIV cannot be cured, but it can be treated to lessen the symptoms and negative effects on the immune system. These medications are called anti-retroviral drugs. There are 25 of these medications in six major types. Most doctors normally recommend that you take three different medications from two of the six groups. Research has shown that a mixture of medications is the best way to control HIV.