Http://wikieducator.org/DeAnza College/CIS2/Summer 2011/Group 5

HIV

• H – Human – This particular virus can only infect human beings.

• I – Immunodeficiency – HIV weakens your immune system by destroying important cells that fight disease and infection. A "deficient" immune system can't protect you.

• V – Virus – A virus can only reproduce itself by taking over a cell in the body of its host.

Human Immunodeficiency Virus is a lot like other viruses, including those that cause the common cold. But there is an important difference – over time the immune system can clear most viruses out of your body. This isn't the case with HIV – the human immune system cannot clear from the body. It is still unknown why this happens. HIV can be dormant for a long period of time in the body. When it becomes active, it attacks a key part the immune system – the T-cells and the CD4 cells. The body has to have these cells to fight infections and disease, but HIV invades them, uses them to make more copies of itself and then destroys them. Over time, HIV can destroy so many of the CD4 cells that the immune system can't fight infections and diseases anymore. When that happens, HIV infection can lead to AIDS.

AIDS

• A – Acquired – AIDS is not something that is inherited. AIDS is acquired after birth

• I – Immuno – The immune system include all the organs and cells that work to fight off infection or disease.

• D – Deficiency –AIDS is contracted when the immune system is "deficient," or isn't working the way it should.

• S – Syndrome – A syndrome is a collection of symptoms and signs of disease.

AIDS is a syndrome, rather than a single disease, because it is a complex illness with a wide range of complications and symptoms Acquired Immunodeficiency Syndrome is the final stage of HIV infection. People at this stage of HIV disease have badly damaged immune systems, which put them at risk for opportunistic infections (OIs). The AIDS diagnosis is given if there is one or more specific OIs, certain cancers or a very low number of CD4 cells

Origin of HIV Scientists identified a type of chimpanzee in West Africa as the source of HIV infection in humans. They believe that the chimpanzee version of the immunodeficiency virus (called simian immunodeficiency virus or SIV) most likely was transmitted to humans and mutated into HIV when humans hunted these chimpanzees for meat and came into contact with their infected blood. Over decades, the virus slowly spread across Africa and later into other parts of the world. Recent studies indicate that HIV may have jumped from monkeys to humans as far back as the late 1800s.

How HIV is Spread

HIV is spread primarily by:

• Not using a condom when having sex with a person who has HIV. All unprotected sex with someone who has HIV contains some risk.

o    Unprotected anal sex is riskier than unprotected vaginal sex.

o   Among men who have sex with other men, unprotected receptive anal sex is riskier than unprotected insertive anal sex.

• Having multiple sex partners or the presence of other sexually transmitted diseases (STDs) can increase the risk of infection during sex. Unprotected oral sex can also be a risk for HIV transmission, but it is a much lower risk than anal or vaginal sex.

• Sharing needles, syringes, rinse water, or other equipment used to prepare illicit drugs for injection.

• Being born to an infected mother—HIV can be passed from mother to child during pregnancy, birth, or breast-feeding.

Less common modes of transmission include:

• Being “stuck” with an HIV-contaminated needle or other sharp object. This risk pertains mainly to healthcare workers.

• Receiving blood transfusions, blood products, or organ/tissue transplants that are contaminated with HIV. This risk is extremely remote due to the rigorous testing of the U.S. blood supply and donated organs/tissue.

HIV cannot reproduce outside the human body. It is not spread by:

• Air or water.

• Insects, including mosquitoes.

Saliva, tears, or sweat. There is no documented case of HIV being transmitted by spitting.

• Casual contact like shaking hands or sharing dishes.

• Closed-mouth or “social” kissing.

Different Type of HIVs

Signs and Symptoms of HIV: As early as 2-4 weeks after exposure to HIV (but up to 3 months later), people can experience an acute illness, often described as “the worst flu ever.” This is called acute retroviral syndrome (ARS), or primary HIV infection, and it’s the body’s natural response to HIV infection. During primary HIV infection, there are higher levels of virus circulating in the blood, which means that people can more easily transmit the virus to others.

Symptoms can include:

• Fever and Chills

• Rash

• Night sweats

• Muscle aches

• Sore throat

• Fatigue

• Swollen lymph nodes

• Ulcers in the mouth

Signs and Symptoms of AIDS

When HIV infection progresses to AIDS, many people begin to suffer from the following symptoms:

• Fatigue

• Diarrhea

• Nausea and Vomiting

• Fever, Chills, and Night Sweats

• Wasting syndrome at late stages.

Diagnosis An HIV test looks for signs of HIV in the body. The most common type of testing is a blood test but there are other kinds of HIV tests that use urine or an oral swab. Some tests take a few days for results, but rapid HIV tests can give results in about 20 minutes.

U.S. Statistics • More than one million people are living with HIV in the U.S.

• One in five living with HIV is unaware of their infection.

• Men who have sex with men of all races remain the group most severely affected by HIV.

• By race, African Americans face the most severe HIV burden.

Global Statistics

• 33.4 million are currently living with HIV/AIDS.

• More than 25 million people have died of AIDS worldwide since the first cases were reported in 1981.

• In 2008, 2 million people died due to HIV/AIDS, and another 2.7 million were newly infected.

• While cases have been reported in all regions of the world, almost all those living with HIV (97%) reside in low- and middle-income countries, particularly in sub-Saharan Africa.

o More than 67 percent (approximately 22.4 million people) of those infected are in sub-Saharan Africa

o In Asia an estimated 4.7 million people were living with HIV in 2008, including the 350,000 people who became newly infected.

o In Latin America there were an estimated 2 million people living with HIV/AIDS in 2008; o In Eastern Europe and Central Asia there were 1.5 million people living with HIV/AIDS

http://aids.gov/index.html

http://www.cdc.gov/hiv/topics/basic/

http://www.who.int/en/