VACCINE: a preparation administered to stimulate an immune response to protect a person from illness. A vaccine typically includes a small amount of a killed or inactivated microorganism, or genetically engineered pieces. A therapeutic (treatment) vaccine is given after infection and is intended to reduce or stop disease progression. A preventive (prophylactic) vaccine is intended to prevent initial infection.
VARICEAL HEMORRHAGE: bleeding from stretched and weakened blood vessels, especially in the esophagus or stomach.
VARICES (adjective VARICEAL): an abnormally dilated or swollen vein, artery, or lymph vessel resulting from portal hypertension.
VASCULITIS: blood vessel inflammation.
VEIN: Any of the membranous tubes that form a branching system and carry blood to the heart from other organs.
VERTICAL TRANSMISSION (PERINATAL TRANSMISSION): transmission from a mother to a fetus or newborn. Vertical transmission may occur in utero (in the womb), intrapartum (during birth), or postpartum (e.g., via breast-feeding).
VICTRELIS (brand name boceprevir): an HCV protease inhibitor taken in combination with pegylated interferon plus ribavirin that was previously used to treat people with HCV genotype 1.
VIRAL CURE: see sustained virological response.
VIRAL HEPATITIS: a type of hepatitis caused by a virus. The most common types are hepatitis A, hepatitis B, and hepatitis C.
VIRAL LOAD: the amount of virus in the blood or other tissues, usually expressed in terms of copies of viral genetic material (RNA or DNA). The presence of genetic material indicates that a virus is actively replicating.
VIRAL LOAD TEST: an assay that measures viral load; the bDNA, PCR, and TMA tests are most often used to determine HCV viral load.
VIRAL RESPONSE: see virological response.
VIREMIA (adjective VIREMIC): the presence of a virus in the blood.
VIRION: a complete virus particle.
VIROLOGICAL FAILURE: failure of a treatment to suppress a virus.
VIROLOGICAL RESPONSE: reduction in viral replication in response to treatment. In HCV, a complete virological response means that a person’s HCV RNA becomes undetectable with treatment.
VIROLOGY: the study of viruses and diseases caused by viruses.
VIRULENCE (adjective VIRULENT): aggressiveness, ability to cause disease.
VIRUS: a microscopic infectious organism that is unable to grow or replicate outside of a host cell. Viruses integrate their genetic material (DNA or RNA) into a host cell and take over the cell’s biological mechanisms to reproduce new virus particles.
VITAMIN: an organic substance that acts as a coenzyme or regulator of metabolic processes; vitamins are crucial for many vital bodily functions.
VITAMIN A: a fat-soluble vitamin synthesized from beta carotene within the body that has antioxidant properties and is important for proper immune system functioning. Excess vitamin A can be toxic to the liver.
VITAMIN B: a complex of several important vitamins including B1 (thiamin), B2 (riboflavin), B3 (niacin), B6 (pyridoxine), and B12 (cobalamin).
VITAMIN B12 (COBALAMIN): a vitamin needed for red blood cell production and DNA synthesis and repair. Vitamin B12 deficiency may result in anemia, neurological dysfunction, and changes in mental status.
VITAMIN C (ASCORBIC ACID): an antioxidant vitamin that protects cells from oxidative damage. Vitamin C deficiency may result in poor healing, easy bruising and anemia.
VITAMIN D: a fat-soluble vitamin that is important for mineral metabolism and which may play a role in immune function. Excess vitamin D can be toxic to the liver.
VITAMIN E (TOCOPHEROL): an antioxidant vitamin that protects cell membranes from oxidative damage.
VITAMIN K: a substance important for blood clotting.
VITILIGO: a condition in which there is loss of pigmentation – usually around the mouth, eyes, nose, elbows, knees and wrists.
