For those with experience of programming, below is simple pseudo code (with scientific dictate) to find out if a virus causes disease.
if (Belief(a virus causes disease)
TakeSputumEtcSampleFromPeople(with similar illness)
v = CharacteriseExogenousOnlyPurified(a virus)
if ExposeWellSubjectsTo(v) != SameIllness
Belief(a virus causes disease) = false
The longer English language version, signed by a couple of medical professionals and supported by over 9000 people around the world, is here.