Brief Answer:
Needs workup and evaluation

Detailed Answer:
Thank you for asking
I read your question and i understand your concern. Pus like saliva with no prior history could point in many directions as there are multiple possibilities that can give such feeling of pus like saliva and bad breath.
Dental abscesses, gums infecfions, parotid glands infections , infections of airways, sinusitis , acid reflux, poor oral hygiene , dehydration, dry mouth irrespective of the cause etc are some of the commonest causes and need to be evaluated for the etiology.
All you need is visit an oral hygienist or a dentist, let them have some tests and analyse your situation to reach a possible cause and then treat you accordingly.
Till them good oral hygiene, judicious fluid intake and salt water and garlic water mouth rinses will help.
I hope it helps. Take good care of yourself and dont forget to close the discussion please.
Regards XXXXXXX

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