Loss of smell can indicate serious pathologies of the nervous system and brain function. Be sure to seek medical care with any unusual and prolonged changed.
Anosmia: loss of smell
Parosmia: distorted smell
Carcosmia: hallucinatory bad smell
Hyperosmia: increased sense of smell
Since COVID, we have seen a lot of smell and taste disorders primarliy involving damage to the nerves coming from the brain. Spike protein (see photo) impairs blood flow and damages tissue, which explains the sudden onset of symptoms.