From The Conservative Treehouse:

An article and video promoted by the World Economic Forum, intended to propose and outline a globally accepted “COVIDPass”, actually reveals stunning background admissions.
The basic premise of the proposal is for a global COVIDPass that will be universally accepted permitting vaccinated people to travel around the world and enter all venues and facilities that require proof of vaccine. However, there is something in the proposal that tells a story all by itself.
The entire premise of the World Economic Forum’s “COVIDPass” is predicated on a blood test being able to identify whether a person has been vaccinated or not.
Think about that carefully.
Right now, all vaccination IDs, and COVID passports, are dependent on a registration process that takes place at the time of vaccination within each nation’s unique healthcare system:
(1) You get vaccinated, you get registered in a system that shows you have been vaccinated; and that’s how you eventually get to a place where you establish a linked “QR” code to the vaccination registration -most commonly on your cell phone- that grants you permitted access at checkpoints or gateways.
-OR-
(2) You get vaccinated, you get registered in a system that shows you have been vaccinated; and you are given a paper vaccination card to carry on your person that grants you permitted access at checkpoints or gateways.
What the World Economic Forum (WEF) is describing is NOT that…. and this is the critical point.
The WEF proposal is based on a blood sample, or a blood test, to prove you have been vaccinated. The only way that is possible is if the vaccine itself carries some form of marker that permanently stays (at a cellular level) in your body which can then be detected in a blood test.
If the vaccine does not leave an identifiable marker or imprint in your blood, then a blood test for vaccinated status would not be possible.
If you were to go into a doctors office, blood lab or hospital right now and tell them you needed a blood test to prove you have been vaccinated, they would look at you like you’re a crazy person. Their response would be for you to contact your healthcare provider -where the vaccine shot was given- to get the verification or duplicate authentication you would need to prove you have been vaccinated.
Yet somehow the World Economic Forum knows of a process for testing blood to see if the vaccine is present? Think about that.
Let’s call whatever is in your blood system a “marker“, because generically we do not know what they would specifically be looking for to isolate blood as vaccinated -vs- non vaccinated. They are looking for something, so let’s call that a marker. That means the following points are evident:
- Whatever that marker is, has to be present in all versions of the vaccine.
- Whatever that marker is, has to be present permanently.
- Whatever that marker is, was known by the World Economic Forum to exist prior to this proposal.
- Without a way to identify vaccinated blood, the entire premise of the COVIDPass proposed by the WEF is moot.
So, the question becomes: what is that marker?
Without extrapolating into conspiracy theory or suspicious imaginings, the basic point to drive home from this WEF proposal is their awareness of a blood test that can guarantee you have been vaccinated.
COMMON SENSE – Factually it would defeat the entire premise of the COVIDPass as outlined if your unique ID was not being traced/tracked.
If, as an example, I were to use your cell phone QR code at the boarding gate of an international flight, there would have to be some cross referenced database that pulls up your unique identification in order to stop me from traveling under your vaccinated status.
Under the concept of a globally accepted, bloodline-authenticated vaccination ID, there has to be a central database from which your vaccination identification -your blood- was registered to your specific personage. But that’s going further into the future.
For now, it is worth noting that in mid-2020, even before the various vaccines deployed in clinical trials, the World Economic Forum knew that a blood test for a COVID vaccination was the best scenario for vaccine passport identification.

Article found here:
https://www.weforum.org/agenda/2020/07/covid-19-passport-app-health-travel-covidpass-quarantine-event/
Video found here:
https://www.youtube.com/watch?v=ABAvzAIAEag