What is the virus responsible for causing Erythema infectiosum?

Erythema infectiosum, commonly known as fifth disease, is primarily caused by Parvovirus B19. This virus is a small, non-enveloped virus that specifically targets and infects erythroid progenitor cells in the bone marrow, which can lead to a characteristic "slapped cheek" rash in children, along with mild fever and other flu-like symptoms. Parvovirus B19 is also known for its association with aplastic crises in individuals with underlying hemolytic anemias due to its effect on red blood cell production.

The other viruses listed do not cause erythema infectiosum. For instance, Varicella Zoster Virus is responsible for chickenpox and shingles. Human Immunodeficiency Virus primarily affects the immune system and is associated with acquired immunodeficiency syndrome (AIDS), while Cytomegalovirus can cause a range of diseases, particularly in immunocompromised patients. Understanding the distinct characteristics of these viruses is crucial in clinical practice, particularly in diagnosing and treating viral infections.