Unit 4- HIV Flashcards
What is the history of HIV?
Early 1980s, United States
- Physicians in New York and California made the first observations of a new infectious disease of homosexual men.
- Sudden appearance of rare skin cancer called Kaposi’s sarcoma
- Atypical pneumonia caused by Pneumocystis carinii
- CMV infections
- Candiasis
- Other observed opportunistic infections
What is (GRID) Gay-Related Immune Deficiecncy?
All observed individuals suffered from immune suppression.
1981: The syndrome was named GRID.
1982: The disease was renamed Acquired Immune Deficiency Syndrome (AIDS).
1983: 2,304 AIDS deaths
1985: Rock Hudson announced he had AIDS and died
Describe the discovery of HIV
Two research teams published results in the journal Science
Robert Gallo’s group, NCI, NIH, United States
Luc Montagnier’s team, Pasteur Institute, France
Both described retrovirus isolated from cultured T cells from lymph node biopsy of an AIDS patient
Upon investigation, Montagnier’s team was the first to isolate HIV.
What is HIV-1 and HIV-2?
HIV-1 isolated by Gallo and Montagnier’s teams was designated HIV-1.
Montagnier isolated another strain that is rare in the United States but endemic to Western Africa, designated HIV-2.
HIV-2 is significantly less infectious and progresses more slowly to AIDS than HIV-1.
Where did HIV come from?
House cat theory
Hunter theory (or crossing the species barrier theory)
Contaminated poliovirus vaccines theory
Colonization (or Heart of Darkness) theory
Conspiracy theory
What is Feline Immunodeficiency Virus (FIV)?
Lentivirus that affects domesticated housecats worldwide
- causative agent of feline AIDS
RElated to HIV
- similar proteins p24
Humans cannot be infected by FIV nor can cats be infected by HIV
What is the Hunter Theory?
(Most commly accpeted theroy)
- HIV is a viral zoonosis.
- Simian immunodeficiency virus (SIVcpz): virus related to HIV-1, that infects chimpanzees (native to Cameroon) thought to have crossed the species barrier.
- Genetic sequences of SIVcpz and early HIV strains are nearly identical
- Naturally infected chimps were killed for food (bushmeat) and eaten; their blood entered cuts or wounds on the hunter.
- Subsequently, SIVcpz adapted to become HIV-1.
- Plasma sample taken from a male in Congo in 1959 found to be seropositive for HIV and contain HIV genetic material
What is the contaiminated Vaccine Theory?
- Initial spread of HIV-1 occurred in Africa during large-scale vaccination campaign
- Multiple patients inoculated with same syringe creating potential for SIV to mutate and spread
- Alternatively, oral polio vaccine suggested to be contaminated with SIV
- Erroneous belief that vaccine was produced in kidney cells from SIV-infected chimpanzees
Where did HIV-2 Originate?
- HIV-2 entered the human population as a zoonosis (like HIV-1).
- Sooty mangabeys are native to Guinea Bissau, Gabon and Cameroon and naturally carry SIVSM.
- SIVSM from sooty mangabeys (an Old World Monkey) likely evolved into HIV-2 when humans acquired it from hunting sooty mangabeys for food and through contaminated blood transfusions and mass vaccination efforts.
- 10% of the general population in Guinea Bissau is HIV-2 sero-positive.
What ist he AIDS pandemic?
Patient Zero vs. The earilest AIDS Cases
- Who was patient zero?
- Randy Shilts book, And the Band Played On, proposed that a homosexual French-Canadian flight attendant who died of AIDS in 1984 was patient zero.
- Unprotected sex with ~2,500 partners
- HIV had been found in blood samples and frozen tissues older than the 1980s.
What is HIV transmission?
- HIV is present in blood, semen, vaginal fluids, breast milk, saliva (low levels), and tears (low levels).
- Most common ways HIV can be transmitted are:
- Anal and vaginal intercourse
- Sharing of contaminated needles (IV drug users)
- Blood transfusions (using infected blood or blood products)
- Accidental needlestick injuries
- Congenital AIDS
- Sharing HIV-contaminated tattoo needles, razors, acupuncture needles, ear-piercing implements
What are the rare routes of HIV transmission?
- Organ transplants
2009: First documented case of HIV transmission from a living donor in the United States - Incident spurred new testing recommendations by the CDC
- Pre-mastication (pre-chewing food)
Three cases reported in the United States
Parent or caregiver pre-masticated food for infants
Can Kissing and Oral SEx Transmit?
- Social kissing is not high risk behavior
- Open mouthed kissing increases risk
- The risk increases if the infected person has canker sores or lesions in his/her mouth
- Oral sex poses similar risks
- HIV infected T lymphocytes from semen may enter abrasions or lesions int he mouth
What are the ways HIV is not transmitted?
- Soap and water easily disrupts HIV.
- HIV is highly susceptible to drying out.
- Contact with sweat, saliva, or tears has never been shown to result in transmission.
- Handshaking and hugging has not resulted in transmission.
- Mosquitoes or other insects cannot transmit HIV.
How do you Prevent HIV?
- Abstinence from sex
- Barrier methods (condoms)
- Microbiocides
- Gels, creams, genetically engineered probiotics
- Fusion and replication inhibitors
- Pre-exposure prophylaxis (PREP) reduces risk
- antiviral drug tenofivir (RT inhibitor)
- Post-exposure prophylaxis (PEP reduces risk)
- Antivirals given within 48 hours of exposure
- 2-3 drugs given over 4 weeks
Talk about AIDS in Africa?
Africa, the world’s largest continent, has been hit harder by HIV/AIDS than any other region of the world.
Poverty, limited access to antivirals, too few healthcare workers
Majority of infected aged 15-49
Each day in Africa:
6,600 people die of AIDS.
8800 people are infected with the HIV virus.
1,400 newborns are infected with HIV virus during birth or through breastfeeding.
At least 12 million children have lost one or more parents to AIDS.
What are some countries in Africa Stabiliizing?
HIV incidence has fallen by more than 35% between 2001 and 2009 in 22 sub saharan countries.
What are the hotspots in worldwide HIV epidemic?
HIV incidence increased by more than 25% in 5 countries in Eastern Europe and Central Asia between 2001 and 2009.
Primary route of transmission is intravenous drug use.
Molecular analysis of HIV strains isolated from people in Belarus, Russia, Kazakhstan, and other former Soviet Union countries evolved from southern Ukraine.
Followed heroin trading routes
Describe AIDS in China
Estimated 740,000 people living with HIV in China
48,000 new HIV infections per year
2009: China reported that AIDS had become the country’s leading cause of death
Home to one of the largest injection drug user populations in the world
Blood product donors and recipients account for 10.7% of HIV infection (2005)
High degree of stigmatization & discrimination of people living with HIV in China
What is the general epidemiology?
HIV cases and deaths among adults adn adolescents diagnosed with AIDS declining since 1993.
How does AIDS/ HIV play a role in U.S. correctional faciliites?
Activities in preisions that pose a risk for HIV transmission
- Homosexual activity
- Intravenous drug use
- Tattooing and body piercing
- Sharing of tooth brushes and shaving equipment
- Incidents of violence
How is AIDs and Seniors in the US relate?
11%–17% of people living with HIV are 50+ years old.
Between 1990 and 2001, cases in seniors quintupled.
24%–30% of men and women ages 60–74 report they are sexually active.
Lack of safe sex practices and disclosures of sexual history
Erectile dysfunction drugs such as Viagra, Cialis, and Levitra has been shown to be associated with higher risk of STDs, especially HIV transmission.
First in-depth study on older adults with HIV (ROAH) over age 50 was released in 2006.
