Here is guide to how to produce a perfectly legit “pandemic” according to the World Health Organisation aka WHO with nothing more than some PCR (or other) test(s).
Let us state upfront that a “pandemic”, according to WHO is defined as ‘ “an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and usually affecting a large number of people”. The classical definition includes nothing about population immunity, virology or disease severity.’
So suppose you got a PCR or any other medical test signifying an infectious agent. Its accuracy is determined by measuring two things: sensitivity and specificity. Whereas sensitivity measures correct positive results and thereby incorrect negative results, specificity measures correct negatives and thereby incorrect positive results.
And without those two parameters — namely sensitivity & specifity — and a third one, namely prevalence defined as the proportion the infected population (which is again hidden and unknow) — it is very difficult to get a viable and reliable estimate of the activity of the infection in a population.
Everything else – and this is exactly what governments and their experts are doing most of the time at the moment – equals reading the tea leaves. In this respect, we have unfortunately (re)turned to the augurs.
Pointedly stated: if specifity is low and few people are infected one tends to greatly overestimate the actual (but unknown) prevalence by concentrating on “a lot” of mostly false positive results. In the limit of nonexistent infectious agent all your positive results are bogus. Or even more concrete: if the specifity is 95% and regulations force 100.000 asymptomatic (without symptoms) home-/incoming tourists to pass the test, then 5.000 false positive tests will be inflicted on these individuals.
This could therefore quite straightforwardly be used to drive policy decisions havoc, and cause a lot of harm and the occasional profits.
Driving forces are, among many other conceivable factors, Angst — the anxiety of the people and their politicians and their tendency to overprotect, a sort of “safer-is-safer” mentality; no matter the opportunity costs, leading to security excesses. No country wants to “perform badly” with respect to peer countries or everybody else, and therefore one effectively gets an international match situation, a competition of sorts.
*) you postulate an infectious disease which is non-existent or so scarce that you can hardly find it, and at the same time
*) succeed to market your PCR test with imperfect specifity then — bingo! You have created a pandemic which satisfies the WHO criteria of a “pandemic”.
From there this “pandemic” is easy to sustain because all testing measures to identify, contain and curb it will result in even more PCR tests — yielding even more positive cases — never mind all or the majority of them are false positives.
Congrats: you just created a vicious cycle of ever increasing case numbers and profits for those involved in testing!
ps: If you are into math and statistical quantitative analysis you can even quantify your “success” and “return on investments” by studying Bayes’ theorem, a standard procedure since maybe around 1800 — yes, this is no typo; spell “eighteen hundred AD”.
pps: If you are into philosophy you might want to contemplate the difference between epistemic and ontic; between what can be known relative to the available (test) means, and what really is. This is an ancient debate starting with Plato’s allegory of the cave and reappearing in many different forms of unknowables.