Notice towards the bottom of the letter they try to prevent hysteria by noting that anxiety and stress in the individual may increase the complications from the influenza. They tried to calm the masses because they know how the body reacts to stress and anxiety when it comes to disease. This is the opposite of what is happening today. They INCREASE stress and anxiety intentionally to INCREASE disease. Something sinister has happened to this country over the last 100 years.
h/t notphysically