If covid-19 negative results can be faked, it is not a far stretch that covid-19 vaccinations can also be faked. As long as there is a centralized system that we all must "trust" as the authority, we continue to have issues that have real-life consequences to covid-19. So, how can blockchain technology be of use? If a public blockchain is available to all to use, a digital identification that proves your identity (your own private key), can be used to authenticate a transaction as belonging to you. If negative test results are on the blockchain, you can always verify your negative test results by scanning your digital identity against the transaction.

Any agency that provides the test results, can record on to the public database, and any agency that wants to verify the test results can validate. As long you keep your digital identity private and secure, no one else can claim your test results like these 190 identical negative test results that these 190 different people claimed belonged to them.

The technology is worth investigating to create a global method to validate test results and be accessible by anyone interested in verifying your negative test results. I fear that vaccination passports will be on the list to fake and unless we can verify the vaccination using a trustless system, we will have a major global health hole which will continue to create havoc for those unvaccinated or those with compromised immune systems. 

In governments that have low trust, a trustless system can function efficiently even with a high trust tax involved. Blockchain is perfect for crossing borders and political boundaries without any issue. One could literally just have a smart phone that has data to the public blockchain, and you'd be good to go. Most countries that allow travel already have this infrastructure, so it seems like a great way to innovate past what we have today.