Rickettsia prowazekii causes epidemic typhus. It is spread by lice. Brill-Zinsser disease is a mild form of epidemic typhus. It occurs when the bacteria re-activates in a person who was previously infected.It is more common in the elderly.t is spread by lice. Brill-Zinsser disease is a mild form of epidemic typhus. It occurs when the bacteria re-activates in a person who was previously infected. It is more common in the elderly.
In this article. When you look at your prescription for eyeglasses, you will see numbers listed under the headings of OS and OD. They are Latin abbreviations: OS (oculus sinister) means the left eye and OD (oculus dextrus) means the right eye. Occasionally, you will see a notation for OU, which means something involving both eyes.
The OU on food packaging (the letter U inside a circle) is the kosher symbol of the Orthodox Union. It is one of the most popular kosher symbols in the United States. Many Orthodox Jews who only eat kosher food will only buy products with this symbol.