Human Immunodeficiency Virus (HIV) Arjun shukla1, Neha Das2 Govt. Model Science College Jabalpur (M.P) Govt. M.H. College of Home Science Jabalpur (M.P.)

IntroductionHuman immunodeficiency virus (HIV) is a lent virus (slowly replicating retrovirus) that causes acquired immunodeficiency syndrome (AIDS), a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Infection with HIV occurs by the transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk. Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells. HIV infects vital cells in the human immune system such as helper T cells (specifically CD4+ T cells), macrophages, and dendritic cells. HIV infection leads to low levels of CD4 + T cells through a number of mechanisms including: apoptosis of uninfected bystander cells, direct viral killing of infected cells, and killing of infected CD4+ T cells by CD8 cytotoxic lymphocytes that recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunity is lost, and the body becomes progressively more susceptible to opportunistic infections.

What is HIV/AIDS? The human immunodeficiency virus, or HIV, is the virus that causes HIV infection. During HIV infection, the virus attacks and destroys the infection-fighting CD4 cells of the body’s immune system. Loss of CD4 cells makes it difficult for the immune system

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to fight infections. Acquired immunodeficiency syndrome, or AIDS, is the most advanced stage of HIV infection.

Natural history of HIV Viral transmission 2-3weeks Acute retroviral syndrome 2-3weeks Recovery and Seroconversion

Asymptomatic chronic HIV infection Av.8years Symptomatic HIV/AIDS Av.1.3 years Death

Virus classification Group: Family: Genus:

Group VI (ssRNA-RT) Retroviridae Lentivirus

Species  Human immunodeficiency virus 1  Human immunodeficiency virus 2

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Comparison of HIV species Species

Virulence Infectivity Prevalence Inferred origin

HIV-1

High

High

Global

HIV-2

Lower

Low

West Africa Sooty Mangabey

Common Chimpanzee

HIV Infection Mechanism

Basic HIV HIV is an enveloped RNA virus: As HIV buds out of the host cell during replication, it acquires a phospholipids envelope. Protruding from the envelope are peg-like structures 3

that the viral RNA encodes. Each peg consists of three or four gp41 glycoproteins (the stem), capped with three or four gp120glycoproteins. Inside the envelope the bulletshaped nucleocapsid of the virus is composed of protein, and surrounds two single strands of RNA. Three enzymes important to the virus's life cycle –  Reverse transcriptase,  Integrase,  Protease - are also within the nucleocapsid.

HIV Transmission HIV is transmitted principally in three ways: by sexual contact, by blood (through transfusion, blood products, or contaminated needles), or by passage from mother to child. Although homosexual contact remains a major source of HIV within the United States, “heterosexual transmission is the most important means of HIV spread worldwide today.”2 Treatment of blood products and donor screening has essentially eliminated the risk of HIV from contaminated blood products in developed countries, but its spread continues among intravenous drug users who share needles. In developing countries, contaminated blood and contaminated needles remain important means of infection. Thirteen to thirty-five percent of pregnant women infected with HIV will pass the infection on to their babies; transmission occurs in utero, as well as during birth. Breast milk from infected mothers has been shown to contain high levels of the virus also. HIV is not spread by the fecal-oral route; aerosols; insects; or casual contact, such as sharing household items or hugging. The risk to health care workers is primarily from direct inoculation by needle sticks. Although saliva can contain small quantities of the virus, thevirus cannot be spread by kissing.

How can I prevent transmitting HIV? To prevent infecting another person with HIV: • Use a condom every time you have sex. 4

• If you inject drugs, don't share your needles or syringes. • Don’t share your razor, toothbrush, or other items that may have your blood on them. • Take your anti-HIV medications according to your health care provider’s directions. • If you are a mother infected with HIV, don’t breastfeed your baby.

The Spread of HIV  Spread through sexual contact, intravenous drug use (infected blood), and mother-to-child during birthing and nursing.  Birthing transmittance rate is 15-30% for mothers infected with HIV.  To minimize risk, antiretroviral therapy is recommend prior to (for the mother) and after birth (for the baby).  Does not spread through mucous membranes, only blood contact.  HIV is a fragile virus  Tip of the Day: Use condoms and clean needles!

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Stages of HIV life cycles 1. Entry into the Cell. Involves 2 steps:

a) Binding b) Fusion- T20 Pentad fuside- new drug. 2. Reverse transcription-

Reverse transcriptase converts HIV RNA to Pro viral DNA.9 out of the 15 drugs act here. 3. IntegrationMediated by Integrase enzyme. Proviral DNA spliced into Human DNA. 4. TranscriptionProcess of making new HIV RNA copies called mRNA.mRNA will use the body’s protein making machinery to make viral proteins. 5. TranslationMaking of HIV structural protein using the host’s protein making machinery. Processed HIV mRNA copies acts as a template. Occurs in the cytoplasm.long chain proteins formed. 6. Assembly and budding, Cleavage of long chain proteins by protease.

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Rapid HIV Testing: CLIA-waived for finger stick, whole blood, oral fluid; moderate complexity with plasma  Store at room temperature  Screens for HIV-1 and 2  Results in 20 minutes

1. Obtain finger stick specimen

2. Insert loop into vial and Stir

3. Collect oral fluid specimens by swabbing gums with test device. Gloves optional; waste not biohazardous.

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4. Insert device; test develops

5.Read results in 20 – 40

in 20 minutes

minutes

Reactive Control Positive HIV-1/2

What is the most common HIV test?  The most common HIV test is the HIV antibody test. HIV antibodies are a type of protein the body produces in response to HIV infection. The HIV antibody test checks for HIV antibodies in a person’s blood, urine, or fluids from the mouth.  Generally it takes the body about 3 months from the time of infection to produce enough antibodies to be detected by an HIV antibody test. (For some people, it can take up to 6 months.) The time period between infection and the appearance of detectable HIV antibodies is called the window period. Because HIV antibodies are not detectable yet, the HIV antibody test isn’t useful during the window period. What does it mean to test HIV positive?  A diagnosis of HIV is made on the basis of positive results from two HIV tests. The first test can be either an HIV antibody test (using blood, urine, or fluids from the mouth) or a plasma HIV RNA test (using blood). The second test(always using blood) is a different type of antibody test called a Western blot test. A positive Western blot test confirms that a person has HIV.

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How long does it take to get HIV test results?  Results of the first antibody test are generally available within a few days. (Rapid HIV antibody tests can produce results within an hour.) Results of the plasma HIV RNA test and Western blot are available in a few days to a few weeks. 

If I test HIV positive now, will I always test HIV positive? Yes. There’s no cure for HIV at this time. Because you will always be infected with the virus, you will always test HIV positive. But treatment with anti-HIV medications can help you live a longer, healthier life.

What treatment is right for Every Person?  The U.S. Department of Health and Human Services (HHS) provides guidelines on using anti-HIV medications to treat HIV infection. The HHS guidelines recommend starting treatment with a regimen of three or more anti-HIV medications from at least two different drug classes. (See the FDA-Approved Anti-HIV Medications fact sheet.) The HHS guidelines list preferred ART regimens. Because people’s needs vary, the preferred regimens may not be right for everyone. You and your health care provider will consider your individual needs to select the most effective regimen for you.

Conclusion:Many HIV-positive people are unaware that they are infected with the virus. For example, in 2001 less than 1% of the sexually active urban population in Africa had been tested, and this proportion is even lower in rural populations. HIV infection is a chronic viral infection that, when untreated, causes a progressive destruction of the immune system resulting in acquired immunodeficiency syndrome (AIDS). Understanding the various components of the immune system and the complex signaling that takes place between immune cells is key to understanding HIV.

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The HIV life cycle is a useful tool for teaching both scientific and spiritual principles in the New Church classroom. A range of biological principles, such as natural selection, drug development and evaluating conflicting scientific evidence, can be illustrated at different course levels ranging from introductory to more in-depth ones. The life cycle of HIV also provides us with excellent opportunities to explore how New Church principles apply to the natural world. The appearance of the syndrome of AIDS has prompted discussions on all levels of life—from personal, to education, to government policy, to global issues. Our New Church understanding of the origins of disease and of the Lord’s Providence has a role to play in the debate on all these levels. We all have something to learn from the spiritual implications of the disease. Diseases are often epidemic, but evil is finite and the HIV virus demonstrates its limitations in as much as it ultimately kills its host as well as itself. All hellish tendencies are self oriented and all selfishness is ultimately unproductive and self-destructive.

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