Human immunodeficiency virus (HIV) attacks and weakens the immune system, impairing the body's ability to fight diseases and infections. Without a healthy, functioning immune system, a person may become vulnerable to infections that can then lead to life-threatening illnesses.
HIV targets and destroys CD4 cells, which is a type of white blood cell (T cell) in the immune system that detects abnormalities and infections in other cells. HIV integrates itself into the DNA of the immune cell and tricks white blood cells into making new copies of the virus. This causes the immune cell to die, releasing the virus into the bloodstream where it goes on to infect the next cell. In this way, the virus multiplies, and the viral load builds up in the body.
In a healthy person, the CD4 count is between 500 and 1,600, but in a person infected with HIV, it can even go below 200. Weakened immunity can make a person prone to infections and other diseases, and it can be difficult to heal even from minor injuries.
If HIV infection is not treated, it can cause acquired immunodeficiency syndrome (AIDS), which is the most advanced stage of HIV infection. There is currently no cure for AIDS.
What are symptoms of HIV/AIDS?
Depending on the stage of infection, symptoms of HIV infection differ. Within 1-2 months of the virus entering the body, the majority of HIV-infected people develop a flu-like illness.
Possible signs and symptoms include:
- Fever
- Headache
- Muscle pain
- Joint pain
- Rash
- Sore throat
- Mouth ulcers
- Swollen lymph glands, mainly in the neck
Symptoms of AIDS include:
- Chills
- Fever
- Sweats
- Swollen lymph glands
- Weakness
- Weight loss
What are the stages of HIV infection?
Most people with HIV in the United States do not develop AIDS because of improved antiretroviral therapy. However, if left untreated, HIV usually progresses to AIDS in about 10 years.
When people contract HIV and do not receive treatment, they usually progress through three stages of the disease:
- Stage I: Acute HIV infection. Within 2-4 weeks of HIV infection, people may develop a flu-like illness that lasts for a few weeks. People with acute HIV infection have a large load of virus in their blood, but they are often unaware that they are infected because they do not feel sick right away or at all.
- Stage II: Clinical latency (HIV inactivity or dormancy). This is sometimes referred to as chronic HIV infection. During this stage, HIV remains active but replicates at a very low rate. People may not experience any symptoms or become ill. This stage can last a decade or longer if HIV medications are not taken, but some people may move through it faster.
- Stage III: AIDS. AIDS is the most severe stage of HIV infection. People with AIDS have such weakened immune systems that they are susceptible to severe and frequent infections and certain types of cancer.
SLIDESHOW
A Timeline of the HIV/AIDS Pandemic See SlideshowHow is HIV transmitted?
HIV is transmitted when HIV-infected blood, sexual bodily fluids or breast milk enters another person's bloodstream. This occurs most common during unprotected sex or intravenous drug use, when needles or other injecting equipment are shared.
HIV is mainly spread in three ways:
- Unprotected sexual intercourse: During sex, HIV can enter the body through the mucous membranes of the anus, vagina, penis, or mouth, as well as through cuts, sores, and abrasions. The most dangerous sexual activities are unprotected anal and vaginal sex. There have been a small number of reported cases of HIV transmission through oral sex. The receptive partner is at high risk of HIV infection. Presence of other sexually transmitted infections may increase the risk of transmission.
- Intravenous drug use: Sharing needles or using non sterile needles and syringes increases the risk of HIV transmission. Infected blood may contaminate needles, syringes, cookers, and cotton after use. It can also contaminate the water used for mixing drugs or bleaching equipment. When any of these items is shared, the virus can enter the body of the next user.
- HIV-positive mother to her infant: During pregnancy, childbirth, or breastfeeding, HIV can be passed from mother to child. With effective antiretroviral drugs to prevent transmission during pregnancy and after delivery, the rate of transmission from an HIV-positive mother to her baby is now less than 1 in 100. Pregnant women should consult their doctor, get tested for HIV, and receive the recommended treatment.
HIV is rarely transmitted in the following ways:
- Blood transfusions and organ transplants: The risk of HIV from a blood transfusion is extremely low today, with estimates ranging from 1 in 200,000 to 1 in 2,000,000 transfusions. The risk of HIV from an organ transplant is comparable. Accepted donors and their blood are thoroughly tested to rule out HIV and other blood-borne germs.
- Healthcare settings: As a result of needlestick accidents and other significant blood exposures, there is a very small, but real, risk of healthcare workers contracting HIV from patients. The risk of patients contracting an infection from healthcare workers is extremely low.
- Casual contact: HIV is not transmitted through casual contact. Outside the body, it dies quickly and is easily killed by soap and disinfectants such as bleach. There is no risk of HIV infection due to the following:
Donating blood
Mosquito bites
Toilet seats
Hugging or kissing
Touching or skin-to-skin contact
Sharing eating utensils
Food or objects handled by people with HIV/AIDS
Spending time in the same house, office, or public place with a person with HIV/AIDS
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What are the treatment options for HIV?
Antiretroviral drugs, which are drugs specifically designed to treat retroviruses, are used to treat acute HIV infection:
- Antiretroviral therapy (ART) is a combination of antiretroviral drugs prescribed to people living with HIV.
- ART reduces the amount of virus in the body (viral load), thereby reducing the risk of transmission. It does not cure HIV infection, but when used properly, it can slow the progression of the disease from one stage to the next.
- ART should begin as soon as possible after HIV diagnosis.
- Missing doses or discontinuing and restarting treatment can result in drug resistance, limiting future treatment options.
A healthcare professional or trained HIV counselor can provide counseling and assist people in locating an appropriate doctor who can advise them on treatment regimens. Moreover, peer support and other support groups can be extremely beneficial in the treatment of HIV.
What are the side effects of HIV treatment?
Some people may consider discontinuing their medication due to the side effects of ART. However, the long-term benefits of ART outweigh the challenges presented by some side effects. It is critical not to discontinue ART without first consulting a doctor, who may be able to prescribe a more tolerable combination of antiretroviral drugs. Recent advancements in ART have resulted in fewer intolerable side effects than in the past.
Side effects associated with taking antiretroviral drugs include:
Doctors can generally tailor ART to a specific person to mitigate potential side effects. Long-term treatment may cause some rare but serious side effects, which include:
- Chronic renal failure
- Diabetes
- Osteoporosis
- Liver damage
- Heart disease
- Hyperlipidemia (excess fat in the blood)
- Lipodystrophy (metabolic changes in how the body uses and stores fat)
- Depression
How can the risk of HIV infection be reduced?
Post-exposure prophylaxis (PEP)
PEP is an antiretroviral drug cocktail intended for use in people who have been exposed to HIV infection. PEP can help prevent HIV infection when taken correctly, but it is not 100% effective. PEP must begin as soon as possible after potential HIV infection and within 72 hours. PEP must be taken exactly as directed by the doctor.
The medications may cause side effects such as:
Pre-exposure prophylaxis (PrEP)
Another method of reducing the risk of acute HIV infection is PrEP. PrEP is medication that can reduce a person's risk of contracting HIV. PrEP is typically prescribed to people who are thought to be at a high risk of contracting HIV. This could include anyone who:
- Is in a relationship with a person who is HIV-positive
- Is considering getting pregnant with a person who is HIV-positive
- Has unprotected sex with people who are also at a high risk of contracting HIV, such as people who inject drugs
- Shares needles or drug equipment
- Has multiple sexual partners
Taken as directed, PrEP can reduce the risk of HIV infection by:
- More than 90% during sex
- More than 70% when injecting drugs.
PrEP should still be used in conjunction with condoms because it does not protect against other sexually transmitted diseases such as gonorrhea.
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How can the risk of HIV transmission be reduced?
Risk of HIV transmission can be reduced with the following measures:
- Practice safe sex: Use condoms during all types of sexual contact and keep the number of partners to a minimum.
- Practice safe needle use: Use only sterile needles and equipment. Healthcare workers and tattoo artists should practice safe needle use.
- Frequent checkups: Consult a doctor as soon as possible if you think you or your partner may have been exposed to HIV. If you think they you any other sexually transmitted infections, seek proper treatment.
Any positive test result should be shared with sexual partners so that they can take appropriate precautions. Doctors advise more frequent testing for anyone who falls into a high-risk category such as someone who:
- Is in a relationship with a person who is HIV-positive
- Has multiple sexual partners
- Shares needles or drug equipment
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HIV the basics: https://www.health.ny.gov/diseases/aids/general/resources/child/docs/chapter_1.pdf
What Is HIV? https://www.webmd.com/hiv-aids/guide/sexual-health-aids
About HIV: https://www.cdc.gov/hiv/basics/whatishiv.html
HOW HIV INFECTS THE BODY AND THE LIFECYCLE OF HIV: https://www.avert.org/about-hiv-aids/how-infects-body
What Does HIV Do to the Immune System? https://prepdaily.org/what-does-hiv-do-to-the-immune-system/
Human Immunodeficiency Virus (HIV): https://www.immunology.org/public-information/bitesized-immunology/pathogens-and-disease/human-immunodeficiency-virus-hiv
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