For its extreme antiquity the virus that causes chicken pox, it has a surprising sparse documented history. The earliest clear reference to the virus is actually to an emergence of its latent form as shingles, also called zoster. The ancient Greeks called it zoster after word for girdle, while shingles comes from the latin word cingulus (belt) both referring to the most common site of emergence along peripheral nerves of the back that wrap around the abdomen. There are many theories, but as far as I know, no one has successfully explained how it got the name chicken pox. It was not until histological and immunological investigations in the early twentieth century that the relationship between the primary phase infection, chicken pox (varicella), and the emergence of the latent virus as shingles (zoster) was confirmed.
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