The vaccine in low doses was deemed safe and effective in order to advance a Phase III clinical trial using two 100 ug doses administered 29 days apart.

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What is the meaning of "ug" and how do you read it?

Thank you. I found it.

microgram1[ mahy-kruh-gram ]SHOW IPA
noun
a unit of mass or weight equal to one millionth of a gram, used chiefly in microchemistry. Symbol: μg

Then, how do you read "μg"?
1. microgram
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Are you sure it's "ug"? Could it be "mg"?

https://www.dictionary.com/browse/microgram?s=t

Click on the little sound icon to hear it pronounced.

The abbreviation "ug" stands for microgram, which is a unit of measurement used to represent a small amount of mass. One microgram is equal to one millionth of a gram.

To read "ug" aloud, you can say it as "microgram." For example, if you see a quantity written as "100 ug," you would read it as "100 micrograms."