Gallery
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.
Hepatitis B is also known as serum hepatitis and is spread through blood and sexual contact. It is seen with increased frequency among intravenous drug users who share needles and among the homosexual population. This photograph is an electronmicroscopic image of hepatitis B virus particles. (Image courtesy of the Centers for Disease Control and Prevention.)
Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.
Last reviewed November 3, 2022 by Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team..