HIV & AIDS

RCS 6080

10/24/06

Some Terms

Virus: Any large group of submicroscopic agents capable of infecting plants, animals and bacteria. They are characterized by a total dependence on living cells for reproduction and by a lack of independent metabolism.

HIV: Human Immunodeficiency Virus. AIDS: Acquired Immune Deficiency

Syndrome

More Terms

Antibody: A protein (immunoglobulin) that is secreted and produced by B lymphocytes when it finds an antigen. Antibodies can bind to and, in turn, destroy certain antigens. When you test positive for HIV, they are actually testing for antibodies.

Antigen: A substance that is recognized as foreign by the immune system. Antigens are either whole microorganisms, or they can be a portion of an organism or virus.

See the handout for a more complete glossary of AID related terms

History

AIDS was first recognized a new disease in 1981. First report in the medical literature was

concerning 5 young, homosexual men living in the Los Angeles area that had Pneumocystis carinii pneumonia and Kaposi's sarcoma.

A few weeks later there was a report from San Francisco and New York about 26 young homosexual men with the same conditions.

This was followed by reports of individuals who had injected drugs with similar conditions.

All of these individuals had profound immunodeficiency suggesting a depletion of CD4-positive, or T-helper, lymphocytes.

History continued

With the prominence of homosexual men and intravenous drug users in the early cases it was originally speculated that these individuals became immunosuppresed because of a history of drug use or because of multiple sexually transmitted diseases.

HIV was 1st identified in a lab in France. Strong evidence did not show up until 1984 when 4 papers were published in one issue of Science.

Several variants of the HIV were discovered during this time.

Transmission

HIV does not survive well in the environment.

HIV is found in varying concentrations or amounts in blood, semen, vaginal fluid, breast milk, saliva, and tears.

There have been rare occurrences of transmission between family members in households: usually resulting from contact between skin or mucous membranes and infected blood.

Some Recommended Precautions (from the CDC) for health professionals and care givers

Gloves should be worn during contact with blood or other body fluids that could possibly contain visible blood, such as urine, feces, or vomit.

Cuts, sores, or breaks on both the care giver’s and patient’s exposed skin should be covered with bandages.

Hands and other parts of the body should be washed immediately after contact with blood or other body fluids, and surfaces soiled with blood should be disinfected appropriately.

Practices that increase the likelihood of blood contact, such as sharing of razors and toothbrushes, should be avoided.

Needles and other sharp instruments should be used only when medically necessary and handled according to recommendations for health-care settings. (Do not put caps back on needles by hand or remove needles from syringes. Dispose of needles in puncture-proof containers out of the reach of children and visitors.)

Other environments

CDC has only found one case of HIV transmission from open mouth kissing

HIV might be able to be transmitted by biting due to trauma and blood interaction

Contact with saliva, tears, or sweat has never been shown to result in transmission of HIV.

Studies conducted by researchers at CDC and elsewhere 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.

Condom use

Numerous studies among sexually active people have demonstrated that a properly used latex condom provides a high degree of protection against a variety of sexually transmitted diseases, including HIV infection.

Acute Retroviral Syndrome

Not all become acutely ill Flu-like illness Very contagious

HIV Antibodies

Develop after infection (varies) Seropositive (Enzyme immunoassay

followed by Western Blot or other tests Clinic or home testing Lymph node biopsy Antigen detection (viral load)

Immunodeficiency

Begins immediately after infection Kills CD4+ T-lymphocyte cells Category 1 >500 cells Category 2 200-499 cells Category 3 <200 cells CD8 lymphocytes attack HIV Triple drug therapy makes a difference!!!!

Asymptomatic HIV Infection

Herpes zoster (“shingles”) Goal of antiretrovial therapy is to

reduce viral load to undetectable

Early HIV

Category A: lymph node swelling, acute infection

Category B: Candidiasis (oral or vaginal), peripheral neuropathy, herpes zoster, fatigue, low energy

Catergory C: 23 qualifying infections e.g. pneumocystis carinni (pneumonia) or kaposi’s sarcoma

Conditions Associated with AIDS

27 clinical conditions can be used in diagnosing AIDS along with HIV + status Include the presence of

“opportunistic infections” that take advantage of weakened immune system

Also include cancer, clinical conditions, and other infections

Conditions Associated with AIDS

Opportunistic infections: Often caused by common bacteria present

in healthy people; immune suppression makes people with AIDS vulnerable

Pneumocystis carinii pneumonia (PCP) Common organism multiplies in lungs Fluid accumulates (pneumonia)

Mycobacterium avium intracellulare Most common tuberculosis in people with AIDS,

may affect many organs Resistant to most antibiotics

Conditions Associated with AIDS

Mycobacterium tuberculosis Occurs in lungs Infectious, but treatable with antibiotics

Bacterial pneumonia Caused by several common bacteria Patient may have many episodes

Toxoplasmosis Disease of brain and central nervous system

(spinal cord) Caused by parasite found in cat feces

Conditions Associated with AIDS

Cancers: Kaposi’s sarcoma

Cancer of the blood vessels Red/purple splotches under skin

Lymphomas Cancer of the lymphatic system/brain

Invasive cervical cancer Can lead to uterine cancer if untreated

Clinical Conditions Associated with AIDS

Wasting syndrome severe weight loss, with weakness and diarrhea

HIV encephalopathy/ AIDS dementia Direct infection of the brain Impairment of mental functioning, changes in

mood Other infections

Candidiasis or “Thrush”: yeast infection of mouth Herpes simplex: persistent lesions of mouth,

lungs, esophagus Cytomegalovirus: infects brain, retina, lungs

Symptoms of HIV Infection and AIDS

Unexplained persistent fatigue

Fever, chills, night sweats

Unexplained weight loss

Swollen lymph nodes Pink, red, purple, or

brown blotches Persistent dry cough Persistent, fuzzy, white

spots in mouth, tongue, or throat

Memory loss or depression

Abnormal pap smears

Persistent vaginal candidiasis

Abdominal cramping (due to Pelvic inflammatory Disease)

Persistent Diarrhea

The Immune System and HIV

Leukocytes – white blood cells Macrophages

Engulf foreign particles Antigens

Stimulate immune system, react with antibodies

Antibodies Inactivate antigens, mark them for

destruction B cells and T cells

Treatment

AZT (zidovudine) Protease inhibitors HAART (highly active anti-retroviral

therapy) Fatality rate dropped from 90% to 5% in

US Secondary treatment of infections &

tumors

AIDS and Its Treatments

Phases of Infection

Time from HIV infection to AIDS variable Ranges from few months to 17 years

Early phase flu-like symptoms

Intermediate phase T cells decrease to 200-500/milliliter of blood

Advanced phase T cells drop to under 200, virus is detectable

in blood Person with AIDS dies from opportunistic

disease

Phases of Infection

Epidemiology of HIV

Epidemic: rapid and wide spreading of a contagious disease

Worldwide, over 36 million people have been infected with HIV 29 million people in sub-Saharan Africa Five million people newly HIV infected each

year In the U.S., 816,000 people are infected About 40,000 people a year are

infected with HIV in the U.S.

Epidemiology of HIV

Populations most affected by HIV/AIDS HIV/AIDS occurs in all population groups Four populations most affected by HIV /AIDS

Men who have sex with men Injection drug users Heterosexual persons

Higher rates for people who use drugs, exchange sex for drugs, have other STIs

Infants whose mothers have untreated HIV infections African Americans are disproportionately

affected Since the mid 1990s: more African-Americans with

AIDS than white Americans in US

Populations most affected by HIV/AIDS

Modes of Transmission

Vaginal or anal intercourse, oral sex without a latex or polyurethane condom or barrier

Sharing needles - drug use, tattooing/piercing

Passing virus from mother to fetus

Modes of Transmission

Breastfeeding from HIV-positive mother

Sharing sex toys Accidental contamination with

infected blood Contaminated blood transfusions

or organ transplants performed before April 1, 1985

Sexual Transmission

Anal intercourse Vaginal intercourse Oral sex Sex toys

STIs and HIV transmission

STIs increase likelihood of HIV infection two to five times

An HIV-infected person also infected with STI is three to five times more likely to transmit HIV through sexual contact

Uncommon Transmission Modes

Nonsexual contact Health care worker risk low with standard

infection control precautions Accidents Blood transfusions and organ donations

Blood has been screened for HIV since 1985

Organs, semen donations screened for HIV

U.S. AIDS Demographics People of Color

Increasing infection among African Americans Gay community

Men who have sex with men 55% of 2001 AIDS cases

Women and HIV Risk from drug use, at-risk sex partners: 26% of

cases Children and HIV

Most due to exposure at birth, HIV positive mother

Teens and college students Half of new infections among young people 13-24

Older adults

U.S. AIDS Demographics by Infection

U.S. AIDS Demographics by Race

Poverty, Ethnicity and HIV

In 2001, minorities were 68% of diagnosed AIDS cases

Race and ethnicity are not risk factors: they correlate with homelessness, access to health care

Poverty, Ethnicity and HIV

AIDS leading cause of death in African-American women 25-34, African-American men 35-44

African-American HIV infection rate 16 times that of Non-Hispanic Whites

Hispanic AIDS incidence four times that of non-Hispanic Whites

Southern U.S. has disproportionate share of cases

Prevention

Be aware that alcohol and drug use increases risky behaviors

Develop communication skills to be able to discuss risks and prevention with partners

Be aware of information on HIV testing

Become familiar with condoms

Education about HIV/AIDS

Prevention has reduced new infections from 150,000/year to 40,000/year

Obstacles to education: blame and denial AIDS seen as disease of marginalized group,

not “us” HIV/AIDS education in schools Outreach programs

Heterosexual adults Men who have sex with men Youths Drug users

HIV Testing

Tests should be taken 12 weeks after high-risk behavior, repeated 6 months after an uncertain result

Types of tests OraQuick Rapid HIV-1 Antibody test

Takes 20 minutes, 99.6% accurate ELISA - enzyme-linked immunosorbent assay Western blot –rechecks ELISA results

Viral load tests measure HIV in bloodstream

Notifying current and past partners

HIV Drugs

Nucleoside reverse transcriptase inhibitors (RT inhibitors) Interrupt virus making copies at early stage

Protease inhibitors Interrupt virus reproduction at later stage

Fusion Inhibitor Block HIV before it enters the cell

HAART – Highly Active Antiretroviral Therapy RT inhibitors and protease inhibitors combined Reduces HIV in blood to undetectable levels

The case of FritzFritz is a 43-year-old single white man that has been HIV

positive for the past six years. He has been getting medical treatment at a county public health AIDS clinic and has been taking AZT for the past 5 years.

Fritz has been employed full-time as a hairdresser at the same medium-sized salon for over 12 years. Lately he has been having problems with fatigue and has complained of loss of concentration and becoming forgetful. He has been occasionally forgetting what his customers tell him and has been making some mistakes while cutting and setting hair. Likewise, he has become rather tired standing all day. A friend who received vocational rehabilitation services years ago for a different condition referred Fritz to VR services. Fritz indicated that he has not told him employer that he is HIV positive, but has a good working relationship with the owner of the salon. Fritz’s physician does not think that he has the symptoms of AIDS as of yet.

Discussion on the case of Fritz

What are the possible functional limitations associated with Fritz’s medical condition that would influence his rehabilitation potential?

How would you explain Fritz’s disability to his employer?

What vocational changes (if any) would you suggest?

Links

CDC HIV transmission fact sheet: http://www.cdc.gov/hiv/resources/factsheets/transmission.htm