 |
|
Glossary
A (top)
ABC
Abstinence, Be Faithful, Condomise - use a condom (a popular HIV/AIDS prevention message).
Accidental Inoculation
An occupational exposure to HIV that occurs during the performance of job duties (by a nurse or doctor, for example). Includes a needle stick or cut with a sharp object, contact of mucous membranes (mouth, eyes), or contact of skin (especially when the exposed skin is chapped, abraded, or afflicted with dermatitis--skin rash or sores--or the contact is prolonged or involving an extensive area) with blood, tissues, or other body fluids (stool, urine, vaginal secretions, saliva, mucous) to which universal precautions apply.
Acquired Immunodeficiency Syndrome (AIDS)
The most severe manifestation of infection with the Human Immunodeficiency Virus (HIV). The Centers for Disease Control and Prevention (CDC), the World Health Organization, and many national governments list numerous opportunistic infections and cancers that, in the presence of HIV infection, result in an AIDS diagnosis. AIDS is also defined on the basis of the degree of immunodeficiency in an HIV-infected individual. AIDS can also affect the central nervous system and can result in neurological problems, infections, or cancers.
Active Tuberculosis
Active disease caused by Mycobacterium tuberculosis, as evidenced by a confirmatory culture, or, in the absence of culture, suggestive clinical symptoms, including productive cough lasting >3 weeks, chest pain, hemoptysis, fever, night sweats, weight loss, and easy fatigability. Active TB is a communicable disease that is treatable, curable, and preventable. Persons with active TB disease should be under the care of a health care provider. Active TB disease may indicate immune deficiency. For HIV-infected persons, active TB disease is considered an opportunistic infection and a qualifying condition for AIDS.
Acute HIV Infection
The period following infection when there is rapid production of virus. An estimated 80 to 90% of individuals with primary HIV infection develop an acute syndrome (disorder) characterized by flulike symptoms of fever, fatigue, swollen lymph nodes, sore throat, headache, aching muscles, and sometimes skin rash. Following infection, the immune system produces antibody and a cellular response to the virus (seroconversion) and a broad HIV-1 specific immune response occurs, usually within an average of 3 weeks after HIV infection. High levels of virus (HIV RNA) can be found in the blood at this time.
AIDS-Related Cancers
Several cancers are more common or more aggressive in persons living with HIV. These malignancies include certain types of immune system cancers known as lymphomas, Kaposi sarcoma, and anogenital cancers that primarily affect the anus and the cervix.
Anal Intercourse/ Anal Sex
A type of sexual intercourse in which a man inserts his penis in his partner's anus. Anal sex can be insertive or receptive.
Anaphylactic Shock
A life-threatening allergic reaction characterised by a swelling of body tissues (including the throat) and a sudden decrease in blood pressure. Symptoms include difficulty breathing, violent coughing, and tightness of the chest.
ANC
Antenatal clinic
Anemia
A lower than normal number of red blood cells.
Anogenital
Related to the anal (rectum) and/or genital (sexual) area of the body.
Anonymous
Without an ability to identify a person. In anonymous testing, patient-identifying information is not linked to testing information, including the request for tests or test results.
Anorexia
The lack or loss of appetite that leads to significant decline in weight.
Antenatal
Occurring before birth.
Antibiotic
A natural or manufactured substance that prevents the growth of bacteria or fungi. Some antibiotics are used to treat infectious diseases.
Antibody
Substances in the blood or other body fluids that destroy bacteria, viruses, or other harmful agents (antigens). They are members of a class of proteins known as immunoglobulins, which are produced by a special white blood cell called B-lymphocytes.
Antigen
Any substance that stimulates the immune system to produce antibodies (proteins that fight antigens). Antigens are often foreign substances such as bacteria or viruses that invade the body.
Antiretroviral
A substance that kills or suppresses a retrovirus, such as HIV.
Antiretroviral Drugs
Substances used to kill or stop the multiplication of retroviruses such as HIV.
Antiviral
A substance or process that destroys a virus or suppresses its replication (i.e. reproduction).
Aphthous Ulcer
A painful mouth or throat sore of unknown cause. Aphthous ulcers are common in persons living with HIV.
ART
Antiretroviral therapy
ARV
See Anteretroviral
Aspergillosis
A fungal infection--resulting from the fungus Aspergillus--of the lungs that can spread through the blood to other organs. Symptoms include fever, chills, difficulty in breathing, and coughing up blood.
Asymptomatic
Without symptoms or not sick. Usually used in HIV/AIDS literature to describe a person who has a positive reaction to one of several tests for HIV antibodies but who shows no clinical symptoms of the disease and who is not sick. Even though a person is asymptomatic he or she may still infect another person with HIV.
B (top)
Bilirubin
A yellow pigment occurring in liver bile, blood, and urine. Its measurement can be used as an indication of the health of the liver. Bilirubin is the product of the breakdown of red blood cells. An elevated level of bilirubin in blood is an indication of liver disease or drug-induced liver impairment.
Bisexual
Having sexual relations with both females and males.
BMI
Body mass index (kilogram/meter2)
Body Fluids
Any fluid in the human body, such as blood, urine, saliva (spit), sputum, tears, semen, mother's milk, or vaginal secretions. Only blood, semen, mother's milk, and vaginal secretions have been linked directly to the transmission of HIV.
Booster
A second or later dose of a vaccine given to increase the immune response to the original dose.
Breakthrough Infection
An infection caused by the infectious agent the substance is designed to protect against. As it pertains to a vaccine trial, the infection may be caused by exposure to the infectious agent, such as HIV, before the vaccine has taken effect, before all doses of the vaccine have been given, or because the vaccine is not effective.
Breast Abscess
This is a collection of pus in part of the breast. It results in painful swelling of the breast and usually requires a surgical incision for drainage.
Breast Milk Substitute
Any food being marketed or otherwise presented as partial or total replacement for breast milk, whether or not suitable for that purpose.
Breast-feeding
Feeding a child breast milk (direct from the breast or expressed).
C (top)
Candida
Yeastlike fungi commonly found in the normal flora of the mouth, skin, intestinal tract, and vagina, which can become infectious in individuals with an abnormal immune system.
Candidiasis
An infection with a yeastlike fungus of the Candida family, generally Candida albicans. Candidiasis of the esophagus, trachea, bronchi, or lungs is an indicator disease for AIDS. Oral or recurrent vaginal candida infection is an early sign of immune system abnormalities.'
Casual Contact
Can be defined as normal day-to-day contact among people at home, school, work, or in the community. A contagious infectious agent (e.g. chicken pox, flu) can be transmitted by casual contact.
CD4 (T4) or CD4+ Cells
A type of lymphocyte involved in protecting against viral, fungal, and protozoal infections. They are also known as T helper cells. They are HIV's preferred targets for infection. Destruction of CD4+ lymphocytes is the major cause of the immunodeficiency observed in AIDS, and decreasing CD4+ lymphocyte levels appear to be the best indicator for developing opportunistic infections.
CD4, CD4 Receptor
One of the protein structures on the surface of a human cell that allows HIV to attach, enter, and thus infect the cell. Present on CD4 cells (helper T lymphocytes) among others.
CD8 (T8) Cells
White blood cells (lymphocytes) with the CD8 protein on their surface. These white blood cells kill some cancer cells and cells infected by bacteria and viruses. Also called cytotoxic T cells, T8 cells, cytotoxic T lymphocytes.
Cervix
The lower part of the uterus that extends into the lower vagina and contains a narrow canal connecting the upper and lower parts of a woman's reproductive tract.
Cesarean Section
A delivery procedure for the baby that involves making a cut through the abdominal wall to remove the baby from the uterus.
Chancroid
A highly contagious sexually transmitted disease caused by the Haemophilus ducreyi bacterium with symptoms appearing 3 to 5 days after exposure.
Chlamydia
A sexually transmitted disease (STD) caused by Chlamydia trachomatis that infects the genital tract. The infection is frequently asymptomatic (i.e. shows no symptoms), but if left untreated, it can cause sterility in women.
Clinical
Pertaining to observations, tests, or treatment of patients.
Clinical Trial
A scientifically designed study of the effects of a drug, vaccine, biologic, or behavior in humans. The goal is to define the safety, the benefit, and side effects of the drug. Most countries require strict testing of all new drugs and vaccines prior to their approval for use.
Cognitive Impairment
Loss of the ability to process, learn, and remember information.
Colitis
Inflammation of the colon, the lower part of the intestine.
Combination Therapy
Two or more drugs or treatments used together to obtain the best results against HIV infection and/or AIDS. Combination drug therapy (treatment) has proven more effective than monotherapy (single-drug therapy) in controlling the growth of the virus. An example of combination therapy would be the use of two drugs such as zidovudine and lamivudine together.
Commercial Sex Worker (CSW)
A woman or man who offers sexual intercourse for a fee. The terms prostitute or prostitution are used more frequently used outside the AIDS area.
Community Planning
Community planning groups are responsible for developing HIV prevention, treatment, and care plans that are used in their communities. The goal of HIV community planning is to improve the effectiveness of HIV programs and to be certain that the needs of the community are being met.
Community-Based Organization (CBO)
A service organization that provides social, support, education, and care services at the local level.
Complementary and Alternative Therapy
Broad range of healing approaches and treatments that Western (conventional) medicine does not commonly use to improve health conditions. Examples include acupuncture, herbs, etc. See
Any food, whether manufactured or locally prepared, suitable as a complement to breast milk or to infant formula, when either become insufficient to satisfy the nutritional requirements of the infant. Such food is commonly called "weaning food" or "breast milk supplement."
Complete Blood Count (CBC)
A frequently ordered blood test that provides the white count, red blood cell count, hematocrit, and hemoglobulin in a microliter of whole blood.
Confidential HIV Test
Performing an HIV test and being certain that the result remains confidential.
Confidentiality
Relating to a piece of information about a person that should not be given to another person without that person's permission. An example would be the result, whether positive or negative, of an HIV test.
Confirmatory Test
Because the diagnosis of HIV infection is so important, a second test, to show that the first test was correct, is recommended. A confirmatory test for an ELISA test is usually the Western blot. A confirmatory test could also be another HIV test such as a rapid test or a DNA or RNA PCR test.
Confirmed Positive
For HIV, a blood sample that is positive on an initial ELISA test, repeatedly positive on a second ELISA run on the same specimen, or confirmed positive on Western blot or other supplemental test indicates that the client is infected.
Contagious
Any infectious disease capable of being transmitted by direct or indirect contact from one person to another.
Controlled Clinical Trials
Performing a study in human in which a control is used. A control is a standard against which study observations may be evaluated. For example, in clinical trials, one group of patients is given an experimental drug, while another group (i.e. the control group) is given either the normal treatment for the disease or a placebo.
Cross-Resistance
The process in which an infectious agent that acquires resistance to one drug through direct exposure also turns out to have resistance to one or more other drugs to which it has not been exposed.
Cryptococcal Meningitis
A life-threatening infection of the membranes surrounding the brain and the spinal cord caused by the fungus Cryptococcus neoformans. Symptoms include headache, dizziness, stiff neck, and, if untreated, coma and death.
D (top)
Diagnosis
The decision that a patient has a specific disease or infection, usually accomplished by evaluating clinical symptoms and laboratory tests.
Diarrhoea
Uncontrolled, loose, and frequent bowel movements caused by diet, infection, medication, and irritation or inflammation of the intestine. Severe or prolonged diarrhoea can lead to weight loss and malnutrition. The excessive loss of fluid that may occur with AIDS-related diarrhoea can be life threatening. There are many possible causes of diarrhoea in persons who have AIDS. The most common infectious organisms causing AIDS-related diarrhoea include Cytomegalovirus (CMV), the parasites Cryptosporidium, Microsporidia, and Giardia lamblia, and the bacteria Mycobacterium avium and Mycobacterium intracellulare. Other bacteria and parasites that cause diarrhoeal symptoms in otherwise healthy people may cause more severe, prolonged, or recurrent diarrhoea in persons with HIV or AIDS.
Disseminated
Spread of a disease throughout the body.
Drug Resistance
The ability of some disease-causing infectious agents, such as bacteria and viruses, to adapt themselves, grow, and multiply even in the presence of drugs that usually kill them.
E (top)
ELISA
(Enzyme-linked immunosorbent assay) A type of enzyme immunoassay to determine the presence of antibodies to HIV in the blood or oral fluids. Repeatedly (i.e. two or more) reactive ELISA test results should be confirmed with a second test such as the Western blot test, a rapid HIV test, or a DNA or RNA PCR. Availability of the confirmatory test often determines which one is performed.
Endpoint
A category of data used to compare the outcome of a clinical trial. Common endpoints are severe toxicity, disease progression, or death.
End-Stage Disease
Final period or phase in the course of a disease leading to a person's death.
Engorgement/Engorged Breasts
Breasts that are over-full, partly with milk and partly with increased tissue fluid and blood. As a result, milk flow is inhibited. Engorged breasts are often painful, shiny, and diffusely red. Nipples may be stretched tight and flat. The condition may be accompanied by fever lasting 24 hours or less.
Epidemic
A disease that spreads rapidly through a part of the human population--such as everyone in a given geographic area, a military base, school, or village--or everyone of a certain age or sex, such as the children or women of a region. Epidemic diseases can be spread from person to person or from a contaminated source such as food or water.
Epidemiology
The branch of medical science that deals with the study and distribution and control of a disease in a population.
Erythrocytes
Red blood cells whose major function is to carry oxygen to cells.
Exclusive Breast-feeding
Feeding an infant only breast milk from his/her mother or a wet nurse, or expressed breast milk and no other liquids or solids with the exception of drops or syrups consisting of vitamins, mineral supplements, or medicines.
Experimental Drug
A drug that is not approved or licensed for use in humans.
F (top)
False Negative
A test result that is not correct. This may be a result of performing the test incorrectly or using a test that is not accurate. A false negative test in HIV would be a test that is negative in a person who is actually infected.
False Positive
A test result that is not correct. This may be a result of performing the test incorrectly or using a test that is not accurate. A false positive test in HIV would be a test that is positive in a person who is not infected. For this reason, a second confirmatory test is recommended when a person tests HIV positive.
Fat Redistribution
Also called body fat redistribution syndrome (BFR). Changes in body fat distribution, sometimes referred to as "lipodystrophy syndrome" or "fat redistribution syndrome," have been observed in patients taking protease inhibitors. Changes may include abdominal fat accumulation ("protease paunch"), fat accumulation over the back of the neck ("buffalo hump"), wasting of legs and arms with prominence of the veins, facial thinning, and breast enlargement.
FP
Family planning
Fungus
One of a group of primitive, nonvascular organisms including mushrooms, yeasts, rusts, and molds.
Fusion Inhibitor
A class of antiretroviral agents that binds to the envelope protein and blocks the structural changes necessary for the virus to fuse with the host CD4 cell. A recently approved drug in this class is enfuvirtide (T-20).
G (top)
Gammaglobulin
One of the proteins in blood serum that contains antibodies obtained from pooled human plasma.
Gamma Interferon
A T-cell-derived stimulating substance that suppresses virus reproduction, stimulates other T cells, and activates macrophage cells.
Gastrointestinal (GI)
Relating to the stomach and intestines.
Gay
Having sexual relations with an individual of the same sex. Usually refers to male-male relations. The term lesbian is most often used for female-female sexual relationships.
Genital Ulcer Disease
Ulcerative lesions on the genitals usually caused by a sexually transmitted disease such as herpes, syphilis, or chancroid. The presence of genital ulcers may increase the risk of transmitting HIV.
Genitals
The area of the sexual organs. In the male, the penis and scrotum. In the female, the vulva and vagina.
Genitourinary Tract
The organs concerned with the production and excretion of urine and those concerned with reproduction. Also called genitourinary system, urogenital system, or urogenital tract.
Genotype
The genetic makeup of an individual organism such as HIV. In reference to HIV, genotypic resistance testing determines whether the HIV genetic structure contains certain mutations that make it resistant to a drug.
Gestation
Pregnancy.
Giardiasis
A common protozoal infection of the small intestine, spread via contaminated food and water and direct person-to-person contact.
Globulins
Simple proteins found in the blood serum containing various substances that function in the immune system function.
Gnorrheao
An infection caused by Neisseria gonorrhoeae. Although gonorrhea is considered primarily a sexually transmitted disease, it can also be transmitted to newborns during the birth process.
H (top)
HAART
Highly Active Antiretroviral Therapy
Helper T Cells
Lymphocytes bearing the CD4 marker that are responsible for many immune system functions, including turning antibody production on and off.
Hemoglobin
The component of red blood cells that carries oxygen.
Hemolysis
The rupture of red blood cells.
Hepatic
Pertaining to the liver.
Hepatitis
An inflammation of the liver. May be caused by bacterial or viral infection, parasitic infestation, alcohol, drugs, toxins, or transfusion of incompatible blood. Although many cases of hepatitis are not a serious threat to health, the disease can become chronic and can sometimes lead to liver failure and death. There are four major types of viral hepatitis: A, B, C, and D.
Hepatitis A
Caused by infection with the hepatitis A virus, which is spread by fecal-oral contact.
Hepatitis B
Caused by infection with the hepatitis B virus (HBV), which is most commonly passed on to a partner during sexual intercourse, especially during anal sex, as well as through sharing of drug needles.
Hepatitis C
Approximately 40% of patients infected with HIV are also infected with the hepatitis C virus (HCV), mainly because both viruses share the same routes of transmission. HCV is one of most important causes of chronic liver disease in the United States. Clinical studies have demonstrated that HIV infection causes a more rapid progression of chronic hepatitis C to liver failure in HIV-infected persons.
Hepatomegaly
Enlargement of the liver.
Herpes Simplex Virus 1 (HSV-1)
A virus that causes cold sores or fever blisters on the mouth or around the eyes, and can be transmitted to the genital region. Stress, trauma, other infections, or suppression of the immune system can reactivate the latent virus.
Herpes Simplex Virus 2 (HSV-2)
A virus causing painful sores of the anus or genitals that may lie dormant in nerve tissue. It can be reactivated to produce symptoms. HSV-2 may be transmitted to a newborn during birth from an infected mother, causing retardation and/or other serious complications. HSV-2 is a precursor of cervical cancer.
Herpes Varicella Zoster Virus (VZV)
The varicella virus causes chicken pox in children and may reappear in adults as herpes zoster. Also called shingles, herpes zoster consists of very painful blisters on the skin that follow nerve pathways.
Herpes Viruses
A group of viruses that includes herpes simplex type 1 (HSV-1), herpes simplex type 2 (HSV-2), Cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella zoster virus (VZV), human herpes virus type 6 (HHV-6), and HHV-8, a herpes virus associated with Kaposi sarcoma. See entries under names of some of the individual viruses.
Herpes Zoster
A painful infection with the varicella virus that normally causes chicken pox. The virus may be dormant for many years in the cells of the nervous system. When reactivated it appears on the skin in various locations as painful sores. Also called shingles.
High-Risk Behavior
A reported sexual, injection drug use, or other non-work-related HIV exposure that might put a patient at high risk for acquiring HIV infection.
Highly Active Antiretroviral Therapy (HAART)
The name given to treatment regimens recommended by HIV experts to aggressively decrease viral multiplication and progress of HIV disease. The usual HAART treatment combines three or more different drugs, such as two nucleoside reverse transcriptase inhibitors (NRTIs) and a protease inhibitor, two NRTIs and a non-nucleoside reverse transcriptase inhibitor (NNRTI), or other combinations. These treatment regimens have been shown to reduce the amount of virus so that it becomes undetectable in a patient's blood.
Histoplasmosis
A fungal infection, commonly of the lungs, caused by the fungus Histoplasma capsulatum. This fungus is commonly found in bird and bat droppings. It is spread by breathing in the spores of the fungus. Persons with severely damaged immune systems, such as those with AIDS, are susceptible to a very serious disease known as progressive disseminated histoplasmosis.
HIV
Human Immunodeficiency Virus.
HIV Prevention Counseling
Provision of information on how HIV is transmitted, how an individual becomes infected, and how to prevent infection. Encompasses all modes of transmission including sexual (homosexual and bisexual), intravenous drug use, mother-to-child transmission, breast-feeding, accidental exposure from an infected patient, and HIV-infected blood transfusion.
HIV Set Point
The point where the level of virus stabilises and remains at a particular level in each individual after the period of primary infection.
Homosexual
Pertaining to sexual activity with a person of the same sex.
Hormone
An active chemical substance formed in one part of the body and carried in the blood to other parts of the body where it stimulates or suppresses cell and tissue activity.
Host Factors
The body's mechanisms for containing HIV, including immune system cells.
HTLV-1; HTLV-2
HTLV-I and HTLV-II, like all retroviruses, are single-stranded RNA that divide through DNA made possible by the presence of a enzyme, reverse transcriptase, which converts a single-stranded viral RNA into a double-stranded DNA. HTLV-I attacks T lymphocytes; it appears to be the causative agent of certain T- cell leukemias, T-cell lymphomas, and HTLV-I-associated neurologic disease.
Human Immunodeficiency Virus Type 1 (HIV-1)
The retrovirus isolated and recognized as the etiologic (i.e. causing or contributing to the cause of a disease) agent of AIDS. HIV-1 is classified as a lentivirus in a subgroup of retroviruses. Also, the genetic material of a retrovirus such as HIV is the RNA itself. HIV inserts its own RNA into the host cell's DNA, preventing the host cell from carrying out its natural functions and turning it into an HIV factory.
Human Immunodeficiency Virus Type 2 (HIV-2)
A virus closely related to HIV-1 that has also been found to cause AIDS. It was first isolated in West Africa. Although HIV-1 and HIV-2 are similar in how they are transmitted and result in similar opportunistic infections, they have differed in their geographic patterns of infection. HIV-1 remains the most common cause of AIDS and represents the major type distributed worldwide.
Human Papilloma Virus (HPV)
HPV is transmitted through sexual contact and is the virus that causes genital warts and plays a causative role in cervical dysplasia and cervical cancer.
Humoral Immunity
The branch of the immune system that relies primarily on antibodies.
Hypergammaglobulinemia
Abnormally high levels of immunoglobulins in the blood. Common in persons with HIV.
Hyperglycemia
An abnormally high concentration of glucose (sugar) in the circulating blood, seen especially in patients with diabetes mellitus. Hyperglycemia, new onset diabetes mellitus, diabetic ketoacidosis, and worsening of existing diabetes mellitus in patients receiving protease inhibitors have been reported.
Hyperlipidemia
An increase in the blood levels of triglycerides and cholesterol (fats) that can lead to heart disease and inflammation of the pancreas. As related to HIV, hyperlipidemia is a side effect of HAART. (All protease inhibitors have been shown to cause hyperlipidemia in clinical studies.)
Hyperplasia
Abnormal increase in the parts of tissue or cells.
Hypogammaglobulinemia
Abnormally low levels of immunoglobulins.
Hypothesis
An assumption as a basis for reasoning or argument, or as a guide to experimental investigation.
Hypoxia
Reduction of oxygen supply to tissues.
I (top)
IDU
Intravenous (injection) drug user
Immune Deficiency
A breakdown or inability of certain parts of the immune system to function, thus making a person susceptible to certain diseases that they would not ordinarily develop.
Immune Response
The activity of the immune system against foreign substances.
Immune System
The body's complicated natural defense against disruption caused by invading foreign agents (e.g. bacteria, viruses). Acquired, or learned, immune response arises when specialized cells (dendritic cells and macrophages) process pieces of infectious agents. The ultimate result is the creation of antibody-producing B cells and cytotoxic T lymphocytes.
Immune Thrombocytopenic Purpura (ITP)
Also called idiopathic immune thrombocytopenic purpura. A condition in which the body produces antibodies against the platelets in the blood, which are cells responsible for blood clotting. ITP is very common in persons infected with HIV.
Immunity
A natural or acquired resistance to a specific disease. Immunity may be partial or complete, long lasting or temporary.
Immunisation
Protection against an infectious disease by vaccination, usually with a weakened (attenuated) or killed form of the disease-causing micro-organism. While people are usually immunised against an infectious disease by getting vaccinated, having a disease such as measles, mumps, or rubella one time usually prevents or "immunises" a person from getting this disease again.
Immunocompetent
Capable of developing an immune response; possessing a normal immune system.
Immunocompromised
Refers to an immune system in which the ability to resist or fight off infections and tumors is subnormal.
Immunodeficiency
Breakdown of the immune system in which certain parts of the immune system no longer function. This condition makes a person more susceptible to certain diseases.
Immunogen
(Antigen) A substance capable of provoking an immune response.
Immunogenicity
The ability of an antigen or vaccine to stimulate an immune response.
Immunoglobulin (Ig)
Also called immune serum globulin. A class of proteins also known as antibodies made by the B cells of the immune system in response to a specific antigen. animal or human studies.)
Incidence
The number of new cases (e.g. of a disease) occurring in a given population over a certain period of time. Also called seroincidence.
Inclusion/Exclusion Criteria
The medical or social standards determining whether a person may or may not be allowed to enter a clinical trial. For example, some trials may not allow persons with chronic liver disease or with certain drug allergies; others may exclude men or women, or include only persons with a lowered T-cell count.
Incubation Period
The time interval between the initial infection with an infectious agent (e.g. HIV) and the appearance of the first symptom or sign of disease.
Indeterminate Test Result
A laboratory test result that does not give a clear answer. Either additional laboratory studies should be performed or the test should be repeated.
Infection
The state or condition in which the body (or part of the body) is invaded by an infectious agent (e.g. a bacterium, fungus, or virus), which multiplies and produces an injurious effect (active infection). As related to HIV, infection typically begins when HIV encounters a CD4+ cell.
Infectious
An infection capable of being transmitted by direct or intimate contact (e.g. sex).
Informed Consent
The permission granted by a patient in a research study (including medical research) after receiving detailed information about the study. This includes, for example, the type of protection available to people considering entering a drug trial. Before entering the trial, participants must sign a consent form that contains an explanation of a) why the research is being done, b) what the researchers want to accomplish, c) what will be done during the trial and for how long, d) what the risks associated with the trial are, e) what benefits can be expected from the trial, f) what other treatments are available, and g) the participant's right to leave the trial at any time. Informed consent also pertains to situations where certain tests need to be performed.
Infusion
The process of administering fluid, other than blood, to an individual by slowly injecting a solution of the compound into a vein. Infusions are often used when the drug is too toxic or the volume is too large to be given by quick injection.
J (top)
Jaundice
Yellow pigmentation of the skin, mucous membranes, whites of the eyes, and body fluids caused by elevated blood levels of bilirubin. The condition is associated with either liver or gallbladder disease or excessive destruction of red blood cells.
K (top)
Kaposi Sarcoma (KS)
An AIDS-defining illness consisting of individual cancerous sores caused by an overgrowth of blood vessels. KS typically appears as pink or purple painless spots or nodules on the surface of the skin or mouth. KS also can occur internally, especially in the intestines, lymph nodes, and lungs, and in this case is life threatening. A species of herpes virus--also referred to as Kaposi sarcoma herpes virus (KSHV) or HHV-8--similar to the Epstein-Barr virus is the probable cause.
Killer T Cells
Because viruses lurk inside host (e.g. human) cells where antibodies cannot reach them, the only way they can be eliminated is by killing the infected host cell. To do this, the immune system uses a kind of white blood cell, called killer T cells. Also known as cytotoxic T cells (or cytotoxic T lymphocytes).
L (top)
Latency
The period when an infecting organism is in the body but is not producing any clinically noticeable ill effects or symptoms. In HIV disease, clinical latency is an asymptomatic period in the early years of HIV infection. The period of latency is characterized by near-normal CD4+ T-cell counts. Recent research indicates that HIV remains quite active in the lymph nodes during this period.
Lentivirus
"Slow" virus characterized by a long time between infection and the onset of symptoms. HIV is a lentivirus, as is the simian immunodeficiency virus (SIV) that infects non-human primates.
Lesion
A general term to describe an area of altered tissue (e.g. the infected patch or sore in a skin disease).
Lipid
Any of a group of fats and fat-like compounds, including sterols, fatty acids, and many other substances.
Long-Term Nonprogressors
Individuals who have been living with HIV for at least 7 to 12 years (different authors use different time spans) and have stable CD4+ T-cell counts of 600 or more cells per cubic millimeter of blood, no HIV-related diseases, and no previous antiretroviral therapy. Data suggest that this phenomenon is associated with the maintenance of the integrity of the lymphoid tissues and with less virus trapping in the lymph nodes than is seen in other individuals living with HIV.
Lymph
A transparent, slightly yellow fluid that carries lymphocytes. Lymph is derived from tissue fluids collected from all parts of the body and is returned to the blood via lymphatic vessels.
Lymph Nodes
Small, bean-sized organs of the immune system, distributed widely throughout the body. Lymph fluid is filtered through the lymph nodes in which all types of lymphocytes take up temporary residence. Lymph nodes contain T cells, B cells, as well as other cells of the immune system.
M (top)
Microbicides
An agent (e.g., a chemical or antibiotic) that destroys microbes. Research is being carried out to evaluate the use of rectal and vaginal microbicides to inhibit the transmission of sexually transmitted diseases, including HIV.
N (top)
Neonatal
Concerning the first 6 weeks of life after birth.
Neoplasm
An abnormal and uncontrolled growth of tissue; a tumor.
Nephrotoxic
Poisonous to the kidneys.
Neurological
Related to the brain, spinal cord, or nerves.
Neuropathy
The name given to a group of disorders involving nerves. Symptoms range from a tingling sensation or numbness in the toes and fingers to paralysis. It is estimated that 35% of persons with HIV disease have some form of neuropathy.
Nucleus
The central controlling body within a living cell, usually a spherical unit enclosed in a membrane and containing genetic codes for maintaining the life systems of the organism and for issuing commands for growth and reproduction.
O (top)
P (top)
Prevalence
The total number of people in a specific population who are living with a particular condition or disease at a given time
Pancreas
A gland situated near the stomach that secretes a digestive fluid into the intestine through one or more ducts and also secretes the hormone insulin.
Pandemic
A disease prevalent throughout an entire country or continent, or the whole world.
Pap Smear
A method for the early detection of cancer and other abnormalities of the female genital tract, especially of the cervix.
Parasite
A plant or animal that lives and feeds on or within another living organism (host), causing some degree of harm to the host organism.
Passive Antibody Transfer
The transfer of antibodies from another person or from an animal, either naturally--as from mother to foetus or to the newborn via breast milk--or by intentional inoculation as in gammaglobulin treatment.
Passive Immunity
Immunity that does not come form immunization. It comes from another individual and is given to a patient in the form of antibodies such gammaglobulin.
Pelvic Inflammatory Disease (PID)
Gynecological condition caused by an infection (usually sexually transmitted) that spreads from the vagina to the upper parts of a woman's reproductive tract in the pelvic cavity. PID takes different courses in different women, but can cause abscesses and constant pain almost anywhere in the genital tract. If left untreated, it can cause infertility or more frequent periods.
PEP
See Postexposure Prophylaxis (PEP).
Perianal
Around the anus.
Perinatal
Pertaining to or occurring in the period shortly before and after birth, variously defined as beginning with completion of the 20th to 28th week of gestation and ending 7 to 28 days after birth.
Perinatal Transmission
Transmission of a pathogen, such as HIV, from mother to baby before, during, or after the birth process.
Plasma
The liquid part of the blood and lymph that contains nutrients, electrolytes (dissolved salts), gases, albumin, clotting factors, wastes, and hormones.
PLWHA
People living with HIV/AIDS
PMTCT
Prevention of mother-to-child transmission (of HIV)
Positive Test
Any result that indicates that a person has a disease or infection. For HIV, a positive test indicates that the person has been infected with HIV.
Postexposure Prophylaxis (PEP)
As it relates to HIV disease, a potentially preventative treatment using antiretroviral drugs to treat individuals within 72 hours of a high-risk exposure (e.g. needlestick injury, unprotected sex, needle sharing) to prevent HIV infection.
Postnatal
Occurring after birth, especially during the period immediately after birth.
Preconception Counseling
Recommended for all women of childbearing age as a component of their primary medical care. The purpose of preconception care is to identify risk factors for adverse maternal or fetal outcome, provide education and counseling targeted to the patient's individual needs, and treat or stabilize medical conditions prior to conception in order to optimize maternal and fetal outcomes.
Prenatal
The period preceding birth, during which the fetus develops in the uterus.
Prevalence
A measure of the proportion of people in a population affected with a particular disease at a given time.
Proteins
Highly complex organic compounds found naturally in all living cells. Proteins are a source of heat and energy to the body. They are essential for growth, the building of new tissue, and the repair of injured tissue.
Protocol
The detailed plan for conducting clinical studies. It states the trial's rationale, purpose, drug or vaccine dosages, length of study, routes of administration, who may participate (Inclusion/Exclusion Criteria), and other aspects of trial design.
PLWHA
Person with living with HIV and AIDS. Also known as PLWA, person living with AIDS
Q (top)
R (top)
Rectum
The terminal section of the large intestine, including the anus
Regimen
A prescribed drug treatment plan, specifying which drugs are to be used, in what doses and on what schedule.
Renal
refers to the kidneys
S (top)
Seroconversion
development of detectable ANTIBODIES to HIV in the blood as a result of infection. It normally takes several weeks to several months for antibodies to the VIRUS to develop after HIV transmission. When antibodies to HIV appear in the blood, a person will test positive in the standard ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA) test for HIV.
Seronegative
testing negative for an infection, such as HIV. Not having ANTIBODIES to a microorganism. A person can be seronegative and still have the infection in question since antibodies take some time to develop (it can take six months for HIV antibodies to become detectable).
Seropositive
testing positive for an infection, such as HIV.
Seroprevalence
the rate of positive SEROSTATUS within a population at a given time point.
Side Effect
any reaction that results from a drug or therapy. The term usually refers to a negative event, such as nausea, blood disorders or NEUROPATHY. EXPERIMENTAL DRUGS must be evaluated for both short- and long-term side effects. Also called adverse effect.
T (top)
Testosterone
The naturally occurring male HORMONE. When administered as a drug it can cause gain in LEAN BODY MASS, increased sex drive and possibly aggressive behavior. Many men with HIV have low testosterone levels.
T Cells (T lymphocytes)
T cells are white blood cells derived from the thymus gland that participate in a variety of cell-mediated immune reactions. Three fundamentally different types of T cells are recognized helper, killer, and suppressor. They are essential for a normal functioning immune system.
Therapy
Any form of treatment. Drugs, radiation, and psychiatric counseling are forms of therapy.
Thrush
Sore patches in the mouth caused by the fungus Candida albicans. Thrush is one of the most frequent early symptoms or signs of an immune disorder. The fungus commonly lives in the mouth, but only causes problems when the body's resistance is reduced either by antibiotics that have reduced the number of competitive organisms in the mouth or by an immune deficiency such as HIV disease. See Candidiasis .
Tissue
A collection of similar cells acting together to perform a particular function. There are four basic tissues in the body: epithelial, connective, muscle, and nerve.
Toxicity
The extent, quality, or degree of being poisonous or harmful to the body.
Transfusion
The process of transfusing fluid (such as blood) into a vein.
Transmission
In the context of HIV disease, HIV is spread most commonly by sexual contact with an infected partner. The virus can enter the body through the mucosal lining of the vagina, vulva, penis, rectum, or, rarely, the mouth during sex. The likelihood of transmission is increased by factors that may damage these linings, especially other sexually transmitted diseases that cause ulcers or inflammation. HIV also is spread through contact with infected blood, most often by the sharing of drug needles or syringes contaminated with minute quantities of blood containing the virus. Children can contract HIV from their infected mothers either during pregnancy or birth, or postnatally through breast-feeding. In developed countries, HIV is now rarely transmitted by transfusion of blood or blood products because of screening measures.
Tuberculosis (TB)
Infection with the bacteria Mycobacterium tuberculosis, as evidenced by a positive tuberculin skin test (TST) that screens for infection with this organism. Sometimes, TST is called a purified protein derivative (PPD) or Mantoux test. A positive skin test might or might not indicate active TB disease. Thus, any person with a positive TST should be screened for active TB and, once active TB is excluded, evaluated for treatment to prevent the development of TB disease. TB infection alone is not considered an opportunistic infection indicating possible immune deficiency.
U (top)
V (top)
Vaccination
Inoculation of a substance (i.e. vaccine) into the body for the purpose of producing active immunity against a disease. Initially associated with smallpox vaccination but now often used interchangeably with immunization. See Vaccine.
Vaccine
A substance that contains antigenic components from an infectious microorganism. By stimulating an immune response--but not the disease--it protects against subsequent infection by that organism. There can be preventive vaccines (e.g. measles or mumps) as well as therapeutic (treatment) vaccines. See Therapeutic HIV Vaccine; Antigen.
Vaginal Candidiasis
Infection of the vagina caused by the yeastlike fungus Candida (especially Candida albicans). Symptoms include, pain, itching, redness, and white patches in the vaginal wall. It can occur in all women, but it is especially common in women with HIV infection. The usual treatment is a cream applied locally to the vagina. Women with HIV infection may experience frequent reoccurrence of symptoms and may require systemic medications in order to treat these symptoms successfully..
Vaginal Intercourse
A type of sexual intercourse in which the man's penis enters the woman's vagina.
Vaginal Sex
Vaginal intercourse.
VCT
Voluntary counselling and testing
Viral Load Test
In relation to HIV, a test that measures the quantity of HIV RNA in the blood. Results are expressed as the number of copies per milliliter of blood plasma. Research indicates that viral load is a better predictor of the risk of HIV disease progression than the CD4 count. The lower the viral load, the longer the time to AIDS diagnosis and the longer the survival time. Viral load testing for HIV infection is being used to determine when to initiate and/or change therapy.
Virology
The study of viruses and viral disease.
Virus
Organism composed mainly of nucleic acid within a protein coat. When viruses enter a living plant, animal, or bacterial cell, they make use of the host cell's chemical energy, protein, and nucleic acid-synthesizing ability to multiply. Some viruses do not kill cells but transform them into a cancerous state. Some cause illness and then seem to disappear, while remaining dormant and later causing another, sometimes much more severe, form of disease. In humans, viruses cause measles, mumps, yellow fever, poliomyelitis, influenza, and the common cold, among others. Some viral infections can be treated with drugs.
Voluntary HIV Testing
An individual is usually counselled regarding HIV prevention and how HIV infection occurs. Participants have the opportunity to accept or refuse HIV testing.
VTC
Voluntary testing and counselling
W (top)
Wasting Syndrome
See AIDS Wasting Syndrome.
Western Blot
A laboratory test for specific antibodies to confirm repeatedly positive results on the HIV ELISA or EIA tests. In the United States, Western blot is the validation test used most often for confirmation of these other tests. In developing countries, a rapid HIV test is utilized most commonly. A positive rapid HIV test should be confirmed by a second rapid HIV test made by a different manufacturer.
WHO
World Health Organization
Window Period
Time from infection with HIV until antibodies are detected.
X (top)
Y (top)
Z (top)
Zidovudine
(ZDV; AZT; Retrovir (trade name)) A nucleoside analogue for treatment of HIV infection and also approved for preventing maternal-fetal HIV transmission.
|
|