In Mosby’s Dictionary, this description is offered:

“... a minute parasitic microorganism much smaller by the bacterium that, having no independent metabolic activity, may replicate only within the cell of a living plant or animal host. A virus consists of a core of nucleic acid … surrounded by a coat of antigenic protein. More than 200 viruses have been identified as capable of causing disease in humans."

CITATIONS & REFERENCES

• Mosby’s Medical, Nursing & Allied Health Dictionary, 6^th Ed.
• Stedman’s Medical Dictionary, 18^th Ed.