Incentivized Covid contact tracing with crypto
cotrace.org
cotrace.org
How / why is a block chain needed for this implementation? 90% of contact tracing is already decentralized and anonymized. If anything block chain will make it easier to finger print individuals by address.
As for fingerprinting - entirely untrue, eth addresses are completely pseudonymous, in stark comparison to App Store/Play Store apps which are tied to your phone number/CC info et al.
You'll need to have verified doctors / tests to generate codes for uploading.