It all started with an unremarkable trip to grandma’s house in 1970. But two days into the visit, something went terribly wrong. The 9-month-old grandson fell ill. First, a fever. Then, a nasty rash.

Smallpox was a severe infectious disease that affected humans for thousands of years before its eradication in the late 20th century. The symptoms included a distinctive rash, pustules, and fever.

Pox virus, illustration. Pox viruses are oval shaped and have double-strand DNA. There are many types of Pox virus including Chickenpox, Monkeypox and Smallpox. Smallpox was eradicated in the 1970’s.