If you wait until World Blood Donor Day to donate your blood, blood stock will shortfall against demand before the World Blood Donor Day because many others are doing so.
Donated blood expires after a month or so (depending on which country you are in).
If you donate on World Blood Donor Day, it is higher chance your blood expires before given to anyone because many others are donating blood on the same day.
Just make an online booking on World Blood Donor Day and consider you participated in it. That should be the new tradition of digital era.
Find out which country has on-line booking system HERE.
Let’s hear what WHO says about it HERE!