Sentence:  In any event , whether society may have cancer , or merely a <WSD>virus</WSD> infection , the `` disease '' , we shall find , is political , economical , social , and even medical . 
Meaning of the word marked with <WSD> tags:  (virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein