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 CIR Recruitment Website Glossary

The purpose of the Recruitment Website glossary is to provide definitions for terms that have a specialized meaning in the scientific field or in clinical research.

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Antibodies are a type of protein. The body's immune system produces antibodies when it detects harmful substances, called antigens. Examples of antigens include microorganisms (such as bacteria, fungi, parasites, and viruses) and chemicals.

Antigen is any substance that causes your immune system to produce antibodies against it. An antigen may be a foreign substance from the environment such as chemicals, bacteria, viruses, or pollen. An antigen may also be formed within the body, as with bacterial toxins or tissue cells

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Blinded or Blinding within a clinical trial, hiding the knowledge of a particular treatment. The three types of blinding are the following: observer-blind—when the researcher does not know the particular treatment that a patient undergoes; single-blind, when only the patient does not know to which group he or she belongs; and double-blind, when both the patient and the one providing the treatment do not know group identity. These types of blinding ensure—all other factors being identical—that any observed results are not the result of bias of the study participants.

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Challenge study is giving the investigational agent or placebo to the subject and then subsequently challenging the subject with the bacteria that the treatment is designed to prevent.

Challenge vrus is the investigational agent that is given to the subject to solicit an antibody response

Clinical trial A clinical trial is a research study to answer specific questions about vaccines or new therapies or new ways of using known treatments. Clinical trials (also called medical research and research studies) are used to determine whether new drugs or treatments are both safe and effective    

Communicable disease is a disease the causative agents of which may pass or be carried from one person to another directly or indirectly.

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Diarrhea is the execessive and frequent evacuation of watery feces.

Dysentery is a general term for a group of gastrointestinal disorders characterized by inflammation of the intestines, particularly the colon.

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Efficacy is the power or capacity to produce a desired effect; effectiveness

Enrolled is agreeing to particiapte in a clinical study after signing an Informed Consent form.

Epidemic is when something is affecting many persons at the same time, and spreading from person to person in a locality where the disease is not permanently prevalent.

Eradicate is to exterminate an infectious agent so that no further causes of the related illness disease can occur.(

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Hemolytic-uremic syndrome (HUS) is a disorder that usually occurs when an infection in the digestive system produces toxic substances that destroy red blood cells, causing kidney injury.

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Indication a reason to prescribe a drug or perform a procedure

Infection  is the growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person.

The term "infection" has some exceptions. For example, the normal growth of the usual bacterial flora in the intestinal tract is not usually considered an infection. The same consideration applies to the bacteria that normally inhabit the mouth.

Immune response is a protective response of the body's immune system to an antigen, especially a microorganism or virus that causes disease. The immune response involves the action of lymphocytes that deactivate antigens either by stimulating the production of antibodies (humoral immune response) or by a direct attack on foreign cells (cell-mediated immune response.)

Immune system protects the body from potentially harmful substances by recognizing and responding to antigens

Informed Consent  a  process by which a subject voluntarily confirms his or her willingness to participate in a particular trial after having been informed of all aspects of the trial that are relevant to the subject's decision to participate. Informed consent is documented by means of a written, signed and dated informed consent form,

Inpatient  is a patient or clinical trial subject  who is admitted to a hospital, clinic or research facility for treatment or research procedures that requires at least one overnight stay

Inpatient Unit is a clinical facility where individuals stay overnight to recieve treatment, intervention or research related procedures. the CIR Inpatient Unit consists of a 30 bed biosafety level 2 isolatio unit at Johns Hopkins Bayview Medical Center. Study participants receive 24-hour clinical care during their stay on the research unit.

Intramuscular (IM) is within a muscle

Intradermal  is within the dermis; within or between the layers of the skin

Irritable bowel syndrome  (IBS) refers to a disorder that involves abdominal pain and cramping, as well as changes in bowel movements.It is not the same as inflammatory bowel disease (IBD), which includes Chron's disease and ulcerative colitis. 

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Lower respiratory  is the part of the respiratory system including the larynx, trachea, bronchi, and lungs. 

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Morbidity is the rate of incidence of a disease

Mortality is the death rate, especially of large numbers

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Outpatient is visits to a hospital or clinic for treatment or procedures that do not require an over-night stay

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Pandemic is an epidemic (a sudden outbreak) that becomes very widespread and affects a whole region, a continent, or the world.

Parasite is an organism that lives in or on and takes its nourishment from another organism. A parasite cannot live independently.

Peritonitis is inflammation of the peritoneum (lining of the stomach), often accompanied by pain and tendernes in the abdomen, vomiting, constipation and moderate fever.

Phase I  clincal studies are all new experimental drugs or biologic agents that are first tyested in laboratories to find out if they meet basic safety standards. These early studies are called "preclinical" trials because they test the new agent in a lab not in people.

Phase II clinical study is an experimental agent that has met basic safety standsrds in a preclinical trial and that has been studied in at least one Phse I trial can than be tested in a Phase II trial.

Phase III  clinical studies are designed to compare the experimental agent to commonly used treatment to see if it is safe and effective.

Phase IV clinical studies are done after an agent is already approved. Since these types of studies are done after the agent is already for sale, they are also called "post marketing studies."

Placebo is an inactive substance or preparation used as a control in an experiment or test to determine the effectiveness of a medicinal drug.or investigational agent

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Renal failure is acute (sudden) kidney failure is the sudden loss of the ability of the kidneys to remove waste and concentrate urine without losing electrolytes. 

Randomized is a clinical trial in which the participatns are assigned randomly, (by change alone) to different treatments or investigational agents

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Screening  process is the initial evaluation of an individual, intended to determine eligibility for a particular treatment modality or participation in a clinical trial that involves detecting health risks or problems by means of history, examination, and other procedures.

Septicemia is the presence of bacteria in the blood (bacteremia) and is often associated with severe infections.

Serotype a group of intimately related microorganisms distinguished by a common set of antigens or the set of antigens characteristic of a serotype

Shedding is the spreading of viruses and bacteria via vaccination.

Side effect is a secondary and usually adverse or unwanted effect of a drug or therapy.

Small pox disease  a serious, contagious, and sometimes fatal infectious disease. There is no specific treatment for smallpox disease, and the only prevention is vaccination. The pox part of smallpox is derived from the Latin word for “spotted” and refers to the raised bumps that appear on the face and body of an infected person.

Study participant

Subcutaneous is when something (i.e. needle) is located or placed just beneath the skin

Symptoms is a subjective indication of a disorder or disease, such as pain, nausea or weakness.

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Upper respiratory is the part of the respiratory system including the nose, nasal passages, and nasopharynx.

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Vaccines are a preparation of a weakened or killed pathogen, such as a bacterium or virus, or of a portion of the pathogen's structure that upon administration stimulates antibody production or cellular immunity against the pathogen but is incapable of causing severe infection.

Vaccine Research  research that facilitates the development of effective vaccines for human disease

Volunteer is a person who does something, especially helping other people, willingly and without being forced rto paid to do it. 

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Withdraw consent

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Glossary Sources::

Centers for Disease and Prevention (

International Conference on Harmonization (ICH) Guideline for Good Clinical Practice E6 (R1). informed consent” Section 1.28 

Merriam-Webster Medical Dictionary (2011)

MedlinePlus (2011) National Institute of Health Library of Medicine (

Cambridge dictionaries online (

National Institute ofAllergey and Infectious Disease (

OneLine Ethics: