I think long COVID is pretty interesting? It is also unpredictable with a new symptom being added every day (200 symptoms and still going).

The funny thing is that a belief in appropriate conspiracy theories holds much survival value. Prominent examples are:

(1) A belief in a supernatural religion is good for getting laid in the same group. (2) A belief in the coming of economic collapse causes one to hoard gold or bitcoin, both of which have appreciated in value relative to holding the dollar in a bank. (3) A belief in the coming of societal collapse, at least at the national level, causes one to become more prepared for potential emergencies. (4) A paranoid belief in the extent of governmental mass surveillance causes one to adopt privacy and cybersecurity technologies.

Wrt Covid and Long Covid, believing in the conspiracy results in taking preparatory at the individual level steps to prepare for the next such virus, if only to boost one's immune system in clever ways.