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Bayes Diagnosis

Insight

The most likely disease is COVID19 (posterior = 0.941209).

Full posterior distribution:
COVID19 posterior = 0.941209 (unnormalized = 0.00154700)
Influenza posterior = 0.029204 (unnormalized = 0.00004800)
AllergicRhinitis posterior = 0.000456 (unnormalized = 0.00000075)
BacterialPneumonia posterior = 0.029131 (unnormalized = 0.00004788)

Explanation

Evidence: Fever=present, DryCough=present, LossOfSmell=present, Sneezing=absent, ShortBreath=present.
Evidence total (normalizing constant) = 0.00164363.
The posterior for each disease is computed as:
posterior(d) = prior(d) × ∏ P(symptom|d) / evidenceTotal
where for an absent symptom the factor is 1 − P(symptom|d).