HIV

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HIV AIDS

• IB Topic 6.3

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Turn and Talk

• What do you know or think of HIV AIDS?

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Talking Point

• http//www.nytimes.com/1987/09/01/opinion/on-my-mi
  nd-our-house-in-arcadia.html

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Introduction

• Human immunodeficiency virus (HIV) is the virus
  that eventually results in a set of symptoms
  collectively called acquired immune deficiency
  syndrome (AIDS)

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Some background information

• 1981
• U.S. healthcare workers noticed an increase in
  the number of cases of Kaposis sarcoma
  pneumonia
• Kaposis sarcoma cancer red/purple lesions on
  the skin, mouth, nose, throat other organs
• These observations led to what came to be known
  as acquired immunodeficiency syndrome (AIDS)
• 1983
• The retrovirus human immunodeficiency virus (HIV)
  was discovered as the cause of AIDS

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Where did HIV come from?

• A lot of different theories conspiracy theories
  
• Molecular studies of HIV reveal the virus
  probably evolved from another HIV-like virus in
  chimpanzees in central Africa
• Believed to have appeared in humans between
  1915-1940
• Unrecognized

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HIV

• There are two strains of HIV
• HIV-1 HIV-2
• HIV-1 is more widely distributed and virulent

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How HIV damages the immune system

• All viruses must find a type of cell in the body
  that matches their own proteins
• This is why only certain body cells are damaged
  by certain viruses reflected in the symptoms
  associated with the particular infection
• Ex a cold virus locates the proteins on the
  mucus membrane cells in your nasal region and
  danger those cells
• Results in swelling of the area and excessive
  mucus production

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How HIV damages the immune system

• The same is true for HIV
• Only certain cells in the body have the protein
  in their membranes that HIV recognizes
• One of those cells
• Is the helper T cell
• More specifically, CD4 receptors
• This is the cell HIV infects

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HIV is a retrovirus

• HIV-RNA is reverse transcribed
• The product DNA is integrated into the host
  genome
• Directs the production of new virus particles
• Because the virus exists within the infected
  cell, the immune system fails to eradicate it

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How this affects the immune system

• Helper T cells communicate which cells need to
  undergo the cloning process and begin antibody
  production
• If these cells die, the communication no longer
  exists
• Antibodies do not get produced
• At this stage, the individual can no longer fight
  off pathogens
• Secondary infections ultimately take the life of
  someone with AIDS

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Other facts/challenges

• Accumulation of mutations from viral replication
• Difficult to develop a vaccine or cure
• HIV has a latency period
• Infection occurs, but cells remain alive
• Usually years after HIV infection before the
  symptoms of AIDS develops

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The stages of HIV infection

• Immune response diminishes viral load however,
  HIV continues to replicate
• Viral load rises
• T cells decrease
• Extensive loss of cell-mediated immunity

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HIV tests

• Detection of HIV-1 antibodies
• Appear in the blood about 1-12 months after
  infection
• Called an ELISA
• Enzyme linked immunosorbent assay

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Symptoms/Stages

• Often asymptomatic
• Initial infection (primary or acute)
• Feels like the flu
• Fever, headache, nausea
• Chronic infection
• Swollen lymph nodes

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(Some) Symptoms of AIDS

• Weight loss
• Reoccurring respiratory tract infection
• Skin rashes/ulcers
• Opportunistic infections
• Pneumonia
• Cancers (Kaposis sarcoma)
• Herpes

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No cure

• HIV cannot be cured progression to AIDS cannot
  be prevented
• Drugs can slow the process
• Slow viral replication
• HAART (highly active antiretroviral treatment)
• May also be administered to people who have been
  exposed take for 28 days
• Also given to newborns for 1 week if mother is
  infected
• Expensive
• Need to be taken properly (if not, mutation can
  occur)

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Statistics (2010 UNAIDS, WHO, UNICEF)

• 35 million people living with AIDS today
• 70 (23 million) live in Sub Saharan Africa
• 1 million in North America
• Fasted growth rate Russia, Eastern Europe
  Central Asia
• Since 2001, HIV prevalence has increased by 250
• Intravenous drug use (opium/heroin) commercial
  sex workers
• Prevalence in Sub Saharan Africa has stabilized
  (but obviously still a problem)

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Transmission

• Bodily fluids
• Semen, pre-ejaculate, vaginal fluid, breast milk,
  blood
• Unprotected sex
• Vaginal, oral, anal
• Drug use
• Sharing needles
• Breast feeding
• Birth (parinatal transmission)
• Blood transfusions
• Not the case anymore all donated blood is
  screened for HIV
• However, this was not the case until the
  mid-1990s
• Numerous cases of people contracting HIV from
  blood transfusion

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Misconceptions/Stereotypes/Stigma

• Originally labeled as a disease affecting
  homosexuals drug abusers
• Back to the group of people in 1980
• This initially led to some reluctance in
  allocated for HIV research
• Rumored that Earvin Magic Johnson was homosexual
  
• AIDS is rapidly spreading among heterosexuals

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Turn and talk

• Should criminalization of HIV transmission be
  enforced?
• Meaning, should a person be tried and/or punished
  by the court of law for having unprotected sex
  without disclosing to his/her partner that he/she
  is HIV positive?
• In some countries, the intentional or reckless
  transmission of HIV is a crime
• Countries that have some law include Australia,
  UK, Canada, Russia, Scotland, Germany, Finland,
  and the US
• 35 US states have prosecuted HIV positive
  individuals for exposing another person to HIV
  (Illinois is one of them)

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Turn and talk

• Discuss the social, emotional, political and
  financial issues related to AIDS

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Issues related to AIDS

• Education
• Access to health care
• Stereotypes
• Employment
• Finances