The exact origins of variolation (also known as “inoculation”) are not well known. However, it is agreed that the practice started somewhere in Asia, in either China or India. (It is possible that it started in both places at around the same time.) In China, scabs from smallpox pustules would be dried in the sun and then inhaled by people seeking to be inoculated. The drying of the scabs would weaken the virus — or make less of it viable — and the inoculated person would (hopefully) not develop the full-blown symptoms of smallpox. In India, the method was similar to what would migrate west to the Middle East, North Africa and eventually Europe. That method involved lancing the pustule of someone recovering from smallpox and then using that same lance to transfer some of the pustule material (pus) into the arm of a healthy person.
A quick podcast on the Balmis expedition, which we covered before in Spanish, as we continue to commemorate 40 years of smallpox eradication.
States are beginning to report influenza-associated deaths, marking the beginning of the influenza season in the United States for 2019-2020.