Mononucleosis, photomicrograph of cells

This is a lymphocyte that has been infected by the Epstein-Barr Virus (EBV) or Cytomegalovirus (CMV) in infectious mononucleosis and is referred to as a "Downy cell". Downy cells may be classified as types I, II, or III; this is a type I Downy cell.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).