Human Immunodeficiency Virus (HIV)Samantha MooreBIOL 2101 – 011 / 012 / 013 Anatomy and Physiology 1 LabDr. Joel QuirosCoastal Bend CollegeNovember 20, 2017Samantha MooreGeneral Overview of HIVHuman Immunodeficiency Virus (HIV) is one of the most common sexually transmitted diseases in the world. When a person is infected with HIV, the virus enters the body and then lives and multiplies primarily in the white blood cells—the immune cells that normally protect us from disease, thus possibly leading to acquired immunodeficiency syndrome (AIDS), the last stage in HIV infection thatcan result in death 1. History of HIVThe prevalence of HIV in the United States was an estimate of 1.2 million people at the end of 2014, the most recent year for which information is available 2.
In 2016, 36.7 million people worldwide were living with HIV and about 4,932 people will become infected with HIV each day—about 205 every hour 3. The earliest known case of infection with HIV in a human was detected in a blood sample collected in 1959 from a man in Kinshasa, Democratic Republic of the Congo 4. Scientist then discovered that HIV crossed from chimps to humans in the 1920’s 5. This was a result of people hunting and eating chimps that were carrying the Simian Immunodeficiency Virus (SIV) (a virus closely related to HIV) in the Congo 5. Symptoms and Causes Most people who have become recently infected with HIV will not have any symptoms 6. Symptoms may not appear for 10 years or more after HIV first enters the body in adults, or within two years in children born with HIV infection Samantha Moore6. However, they have a flu-like illness within a month or two after exposure to the virus, with fever, headache, tiredness, and swollen lymph nodes in the neck and groin 6.
These symptoms usually disappear after a couple of days or weeks and are often mistaken for those of other viral infections 6. During this period, people are very infectious, and HIV is present in large quantities in blood, semen, and vaginal fluids 6. A health-care provider can diagnose HIV by testing blood for the presence of antibodies (disease-fighting proteins) to HIV.
It may take HIV antibodies as long as six months after infection to be produced in quantities large enough to show up in standard blood tests 7. On the other hand, new, more expensive test are now available called an RNA test that looks for the virus itself and can diagnose HIV about 10 days after one has been exposed 7. Furthermore,only certain body fluids like blood, semen, pre-seminal fluid, rectal fluids, vaginalfluids, and breast milk from a person who has HIV can transmit HIV. These fluidsmust come in contact with a mucous membrane or damaged tissue or be directly injected into the bloodstream (from a needle or syringe) for transmission to occur 8. A less common way of infection to be transmitted is from mother to child during pregnancy, birth, or breastfeeding.
Although the risk can be high if a mother is living with HIV and not taking medicine, recommendations to test all pregnant women for HIV and start HIV treatment right away have lowered the number of babies who are born with HIV 8.Physiological effects of HIVOnce the virus has made its way into the body, the virus is able to recognize and infect certain types of immune cells, particularly targeting and destroying cells Samantha Mooreknown as helper T cells, or CD4+ T cells that play a crucial role in defending the body against bacterial and fungal infections 9. When the CD4 count drops below200 due to advanced HIV disease, a person is diagnosed with AIDS 10.
A normal range for CD4 cells is about 500-1,500 10. Usually, the CD4 cell count increases as the HIV virus is controlled with effective HIV treatment 10.Current TreatmentsUnfortunately, there is not a cure for HIV. But it can be treated through a combination of two different kinds of drugs: inhibitors (CCRS, integrase, protease) and nukes and non-nukes, 11.
The aim of treatment is a very low level of HIV in blood 11. CCRS inhibitors try to stop HIV from attaching to CD4 cells 11. While nukes and non-nukes stop HIV from changing shape inside of the cell 11. Integrase inhibitors stops HIV from hiding deeper in the cell 11. And protease inhibitor drugs try to prevent HIV from multiplying within the cell 11. There are a few ways to prevent the risk of HIV like to wear a condom, lower the number of one’s sexual partners, and there is also a daily pill you can take called PrEp that can help prevent 12.
ConclusionIn summary, HIV is a sexually transmitted drug that has affected 37 million people worldwide. The first case and origin of the virus was in the Democratic Republic of the Congo. Symptoms are flu-like but may never appear and to be diagnosed requires a blood test. HIV is incurable, but can be treated through a series of drugs that help block HIV in different ways.Samant