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  1. 1. You may have heard about HIV and AIDS, but many people don't know the basic facts about them. HIV causes AIDS. HIV stands for human immunodeficiency virus. It breaks down the immune system — our body's protection against disease. HIV causes people to become sick with infections that normally wouldn't affect them. AIDS is short for acquired immune deficiency syndrome. It is the most advanced stage of HIV disease.
  2. 2. Origin of HIV • Scientists believe HIV came from a particular kind of chimpanzeE in Western Africa. • Humans probably came in contact with HIV when they hunted and ate infected animals. Recent studies indicate that HIV may have jumped from monkeys to humans as far back as the late 1800s.
  3. 3. • The earliest well documented case of HIV in a human dates back to 1959 in the Congo. The vast majority of infections occurring outside sub-Saharan Africa (including the U.S.) can be traced back to a single unknown individual who became infected with HIV in Haiti and then brought the infection to the United States some time around 1969. • The epidemic then rapidly spread among high-risk groups (initially, sexually promiscuous men who have sex with men). By 1978, the prevalence of HIV-1 among gay male residents of New York and San Francisco was estimated at 5%, suggesting that several thousand individuals in the
  4. 4. Discovery  AIDS was first clinically observed in 1981 in the United States. The initial cases were a cluster of injecting drug users and homosexual men with no known cause of impaired immunity who showed symptoms of Pneumocystis carinii pneumonia (PCP), a rare opportunistic infection that was known to occur in people with very compromised immune systems.  Soon thereafter, an unexpected number of gay men developed a previously rare skin cancer called Kaposi's sarcoma (KS). Many more cases of PCP and KS emerged, alerting U.S. Centres for Disease Control and Prevention (CDC) and a CDC task force was formed to monitor the outbreak. Robert Gallo, co-discoverer of HIV in the early eighties among (from left to right) Sandra Eva, Sandra Colombini, and Ersell Richardson.
  5. 5.  In the early days, the CDC did not have an official name for the disease, at one point, the CDC coined the phrase "the 4H disease", since the syndrome seemed to affect Haitians, homosexuals, haemophiliacs, and heroin users.  In the general press, the term "GRID", which stood for gay-related immune deficiency, had been coined. However, after determining that AIDS was not isolated to the gay community, it was realized that the term GRID was misleading and the term AIDS was introduced at a meeting in July 1982. By September 1982 the CDC started referring to the disease as AIDS.
  6. 6. Each virion comprises a viral envelope and associated matrix enclosing acapsid, which itself encloses two copies of the single-stranded RNA genome and several enzymes.
  7. 7. • HIV particles are much too small to be seen through an ordinary microscope. • HIV is different in structure from other retroviruses. • It is around 120 nm in diameter (around 60 times smaller than a red blood cell) and roughly spherical. • Like other viruses, HIV does not have a cell wall or a nucleus. • The Structure of HIV is made up of a viral envelope and viral core.
  8. 8. •HIV particles surround themselves with a coat of fatty material known as the viral envelope (or membrane). • Projecting from this are around 72 little spikes, which are formed from the proteins gp120 and gp41. Just below the viral envelope is a layer called the matrix, which is made from the protein p17. • The viral core (or capsid) is usually bullet-shaped and is made from the protein p24. Inside the core are three enzymes required for HIV replication called reverse transcriptase, integrase and protease. • Also held within the core is HIV's genetic material, which consists of two identical strands of RNA. At either end of each strand of RNA is a sequence called the long terminal repeat, which helps to control HIV replication.
  9. 9. • HIV has just nine genes (compared to around 20,000-25,000 in a human). • Three of the HIV genes, called gag, pol and env, contain information needed to make structural proteins for new virus particles. • The other six genes, known as tat, rev, nef, vif, vpr and vpu, code for proteins that control the ability of HIV to infect a cell, produce new copies of virus, or cause disease.
  10. 10. HIV Lifecycle    Host cells infected with HIV have a very short lifespan. HIV continuously uses new host cells to replicate itself. During the first 24 hours after exposure, the virus attacks or is captured by dendritic cells (type of phagocyte) in mucous membranes and skin.
  11. 11. Phases: binding and entry, reverse transcription, replication, budding, and maturation
  12. 12. HIV (arrows) Infecting a Tlymphocyte
  13. 13. Common Side Effects of HIV Drugs Nucleoside Reverse Common Side Effects Transcriptase Inhibitors (NRTIs) Special Precautions Ziagen (abacavir) Hypersensitivity reaction Have genetic testing done prior to therapy Epzicom (abacavir + lamivudine) Nausea, vomiting, Bactrim or Septra may upsetstomach, increase blood levels; do diarrhea, fatigue, not take with stavudine chills, dizziness, headaches, insomnia Diarrhea, abdominal Do not combine with pain,neuropathy, nausea, stavudine. vomiting, pancreatitis Videx, or Videx-EC (didanosine or ddl) Retrovir (AZT, zidovudine) Anemia, nausea, vomiting Do not combine with stavudine.
  14. 14. Non-Nucleoside Reverse Common Side Effects Transcriptase Inhibitors (NNRTIs) Edurant (rilpivirine) Depression, difficulty sleeping, headache, rash Sustiva (efavirenz) Special Precautions Vivid dreams, anxiety, rash, nausea, insomnia Viramune (nevirapine) Skin rash, fever, headache, nausea, diarrhea Liver problems.
  15. 15. • ELISA Test :• ELISA, which stands for enzymelinked immunosorbent assay, is used to detect HIV infection. If an ELISA test is positive, the Western blot test is usually administered to confirm the diagnosis. If an ELISA test is negative, but you think you may have HIV, you should be tested again in one to three months. ELISA is quite sensitive in chronic HIV infection, but because antibodies aren't produced immediately upon infection, you may test negative during a window of a few weeks to a few months after being infected. Even though your test result may be negative during this window, you may have a high level of the virus and be at risk of transmitting infection.
  16. 16. • Home Tests:• The only home test approved by the U.S. Food and Drug Administration is called the Home Access Express Test, which is sold in pharmacies. • Saliva Tests:• A cotton pad is used to obtain saliva from the inside of your cheek. The pad is placed in a vial and submitted to a laboratory for testing. Results are available in three days. Positive results should be confirmed with a blood test. • Western Blot:• This is a very sensitive blood test used to confirm a positive ELISA test result.
  17. 17. • PCR Test (Polymerase chain reaction test):- This test detects the genetic material of HIV itself, and can identify HIV in the blood within 2-3 weeks of infection. Babies born to HIV-positive mothers are tested with a special PCR test, because their blood contains their mother's HIV antibodies for several months. This means they would test HIV-positive on a standard antibody test—but a PCR test can determine whether the babies have HIV themselves. Blood supplies in most developed countries are screened for HIV using PCR tests. PCR tests are also used to measure viral loads for people who are HIV-positive.
  19. 19. The first stage is called acute infection or seroconversion, it happens within two to six weeks after becoming infected. This is when the body's immune system puts up a fight against HIV. The symptoms of acute infection look similar to those of other viral illnesses. The symptoms may last a week or two and then completely go away as the virus goes into a non-symptomatic stage. The initial symptoms of acute HIV may include: 1.Headache 5.Diarrhea 2.Nausea and vomiting 6. Fatigue 3.Aching muscles throat 7.Sore 4.Red rash that doesn't itch 8. Fever
  20. 20. The asymptomatic latent phase The second phase of HIV infection is the asymptomatic latent or silent phase.  In this stage, an infected person displays no symptoms. Infected individuals are often not even aware that they are carrying the HI virus in this stage, and may therefore unwittingly infect new sex partners. A positive HIV antibody test is often the only indication of HIV infection during this latent phase. HIV-infected people can remain healthy for a long time, show no symptoms and carry on with their work in a normal way. Some people remain HIV positive for many years without any manifestation of clinical disease while others may deteriorate rapidly, develop Aids and die within months. In some cases the only symptom during this phase is swollen glands. 
  21. 21. THE LAST STAGE : AIDS The Aids patient is usually very thin and emaciated due to continuous diarrhea, nausea and vomiting which may last for weeks or even for months. Conditions in the mouth (such as thrush and sores) may become so painful that the patient is no longer able to eat. Women suffer from persistent, recurrent vaginal infections and cervical cancer. Severe skin infections, warts and ringworm. Respiratory infections, persistent cough, chest pain and fever. Nervous system problems - often complain of pains, numbness Neurological abnormalities with symptoms such as memory loss, poor concentration, tremor,
  22. 22. In the final stage of Aids, the symptoms of HIV disease become more acute, patients become infected by relatively rare and unusual organisms that do not respond to antibiotics, the immune system deteriorates, and more persistent and untreatable opportunistic conditions and cancers begin to manifest. While people with Aids (the last phase of HIV disease) usually die within two years, anti-retroviral therapy and the prevention and treatment of opportunistic infections may prolong this
  23. 23. Why is there stigma related to HIV and AIDS? Factors that contribute to HIV/AIDS-related stigma include: HIV/AIDS is a life-threatening disease, and therefore people react to it in strong ways. HIV infection is associated with behaviours (such as homosexuality, drug addiction, prostitution or promiscuity) that are already stigmatised in many societies. Most people become infected with HIV through sex, which often carries moral baggage. There is a lot of inaccurate information about how HIV is transmitted, creating irrational behaviour and misperceptions of personal risk. HIV infection is often thought to be the result of personal irresponsibility. Religious or moral beliefs lead some people to believe that being infected with HIV is the result of moral fault (such as promiscuity or 'deviant sex') that deserves to be punished. The effects of antiretroviral therapy on people’s physical
  24. 24. General effects of stigma •Loss of income/livelihood •Loss of marriage & childbearing options •Poor care within the health sector •Withdrawal of care giving in the home •Loss of hope & feelings of worthlessness •Loss of reputation
  26. 26. TRANSMISSION RISK CAUSE ANAL SEX VERY HIGH The rectum is a fragile tissue prone to tears when penetration occurs. DRY SEX VERY HIGH It involves the removal of the natural lubrication in the vaginal tract, increasing risk of tearing. VAGINAL SEX HIGH Risk increases during a woman’s menstrual cycle, and also with the presence of sexually transmitted diseases. ORAL SEX LOW/MEDIU M Risk may be increased through poor oral hygiene, which includes the presence of bleeding gums and sores. SEX WITH CONDOM VERY LOW Providing the condom is of good quality and is placed over the penis correctly, or the femidom inserted into the vagina correctly.
  27. 27. • Via blood and blood products. • Blood-borne transmission can be through needlesharing during intravenous drug use, needle stick injury, transfusion of contaminated blood or blood product, or medical injections with unsterilised equipment. • Injecting drugs. • Healthcare workers have the greatest risk for this type of HIV transmission. • Blood transfusion with infected blood or an organ
  28. 28. This type of transmission is very rare. These transmissions are believed to have resulted from contact between skin or mucous membranes and infected blood. To prevent even such rare occurrences, precautions, should be taken in all settings
  29. 29. From the onset of the HIV epidemic, there has been concern about transmission of the virus by biting and bloodsucking insects studies have shown no evidence of HIV transmission through insects--even in areas where there are many cases of AIDS and large populations of insects such as mosquitoes. Lack of such outbreaks, despite intense efforts to detect them, supports the conclusion that HIV is not transmitted by insects HIV lives for only a short time inside an insect and, unlike organisms that are transmitted via insect bites, HIV does not reproduce
  30. 30. PREVENTION  Sexual contact  Consistent condom use reduces the risk of heterosexual HIV transmission by approximately 80% over the long-term. Where one partner of a couple is infected, consistent condom use results in rates of HIV infection for the uninfected person of below 1% per year.  Oral sex  The risk of HIV transmission through the throat, gums or any other oral membranes has a lower risk then receiving it from the vaginal or anal area.
  31. 31.  Mother-to-child  Prevention method primarily involves the use of a combination of antiviral medications during pregnancy and after birth in the infant and potentially includes bottle feeding rather than breastfeeding.  Vaccination  As of now there is no effective vaccine for HIV or AIDS. A single trial of the vaccine RV 144 published in 2009 found a partial reduction in the risk of transmission of roughly 30%, stimulating some hope in the research community of developing a truly effective vaccine. Further trials of the RV 144 vaccine are on-going.
  32. 32. • Personal articles like toothbrush and razors should not be shared with other family members • When donating or getting blood, make sure get those only in hospitals/clinics that use disposable syringes and conduct HIV testing are some ways to make sure that you don’t contract HIV. Also if you want to get tattoos get them from hygienic places which follow basic safe practices. • Gloves should be worn when handling blood specimens & other body secretions as well as surfaces, materials and objects exposed to them. • Avoid accidental pricks from sharp instruments contaminated with potentially infectious materials from AIDS patient.
  33. 33. Treatment For HIV  AIDS drugs are medicines used to treat but not cure HIV infection.  These drugs are sometimes referred to as “anteroviral drugs”, work by reducing the replication of the virus.
  34. 34. There is ACTUALLY no cure for AIDS . 1. Antiretroviral therapy - reduce the presence of the virus in the body, but can not eliminate it. Nucleoside Reverse Transcriptase inhibitors (Zidovudine) Non-Nucleoside Transcriptase inhibitors (Nevirapine) Protease inhibitor (Ritonavir) Taking two or more antiretroviral drugs at a time is called combination therapy. If only one drug was taken, HIV would quickly become resistant to it. 2. Opportunistic Infection Treatment Used in an event where antiretroviral drugs are not available
  35. 35. 2 groups of Anteroviral drugs Reverse Protease transcriptase inhibitors inhibitors  inhibits the  inhibits the enzyme enzyme “reverse transcriptase” protease which which is needed to are needed for “copy” information for the the assembly of virus to replicate. viral particles.  Zalcitabine  Saquinavir -Havid -Invarase Stavudine -Zerit
  36. 36. What is needed now are increased efforts to promote youth participation and commitment; more services aimed at youth; more parental involvement; more education and information, using schools and other sites; more protection for girls, orphaned children and young women; and more partnerships with people with HIV and AIDS!!