Transverse myelitis: An abrupt onset inflammatory process involving almost the entire thickness of the spinal cord but of limited longitudinal extent, generally one or a few segments; of multiple etiologies, the most common being viral and postviral causes, and multiple sclerosis.1

Urticaria: An eruption of itching wheals, collquially called hives, usually of systemic origin; it may be due to a state of hypersensitivity to foods or drugs, foci of infection, physical agents (heat, cold, light, friction), or psychic stimuli.1

Vaccine Adverse Event Reporting System (VAERS): A database managed by the Centers for Disease Control and Prevention and the Food and Drug Administration. VAERS provides a mechanism for the collection and analysis of adverse events associated with vaccines currently licensed in the United States. Reports to VAERS can be made by the vaccine manufacturer, recipient, their parent/guardian, or health care provider. For more information on VAERS call (800) 822-7967.5

Vaccine Safety Datalink Project (VSD): To increase knowledge about vaccine adverse events, the Centers for Disease Control and Prevention has formed partnerships with eight large health management organizations to continually evaluate vaccine safety. The project contains data on more than 6 million people. Medical records are monitored for potential adverse events following immunization. The VSD project allows for planned vaccine safety studies as well as timely investigations of hypothesis.5

Varicella: An acute contagious disease, usually occurring in children, caused by the varicella zoster virus genus, Varicellovirus, a member of the family Herpesviridae, and marked by a sparse eruption of papules, which become vesicles and then pustules, like that of smallpox although less severe and varying in stages, usually with mild constitutional symptoms; incubation period is about 14–17 days.1

Vasculitis: Inflammation of a blood vessel (arteritis, phlebitis) or lymphatic vessel (lymphangitis).1


1This definition was obtained from Stedman’s Medical Dictionary. The citation for the term is Stedman, Thomas Lathrop. 2006. Stedman’s medical dictionary. Philadelphia: Lippincott Williams & Wilkins. © 2006.

2This definition was obtained by searching the term in the A.D.A.M. Medical Encyclopedia, a source used by the National Center for Biotechnology Information (NCBI), a division of the National Library of Medicine (NLM) at the National Institutes of Health (NIH). The citation

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