Fig. 2: Flowchart of participants in the serologic subsample in Ensanut 2020.

The flowchart of participants in the National Health and Nutrition Survey (Ensanut 2020). From the 36,024 subjects selected at the household level, a subsample of 21,707 were randomly selected to participate in the serologic sample. From those some could not be contacted and others declined to participate. We collected 9,640 venous samples.