Flu vaccine effectiveness from the CDC website

[littlejohnny]

Flu vaccine effectiveness from the CDC from the CDC web site at https://www.cdc.gov/flu/vaccines-work/2018-2019.html and the corresponding paper at https://academic.oup.com/jid/article/221/1/8/5609441

I'm trying to make sense of the numbers. Statistics can be interpreted subjectively by people.

My interpretation:

-Total flu cases=2763

-Of the 2763, the number that were vaccinated for the flu = 1316

My initial conclusion:

-Nearly half of the people who have the flu (1316/2763) had the flu shot.

-We do not have number as to how many who were not vaccinated did not get the flu. This would be a very interesting number to have.

Do my interpretations and conclusions stand scrutiny?

Assumptions:

All people with flu have sought medical help.