Brief Answer:
Needs evaluation. Likely viral / fungal

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Sore throat is a symptom and pharyngitis ( inflammation of pharyngeal mucosa ) is the disease. Strep thrat is the cause but over rated one. That means sore throat is treated aggressively when not every one is strept. Mostly sore throats are virals and self resolves all a person needs is symptomatic care and home remedies.

How to tell a difference? Swab test. A simple throat swab test will confirm the diagnosis of strept presence. If it comes strept it will need antibiotic. if not it will be labelled viral and anti inflammatory meds and gargles of aspirin will be advised. Short term use of corticosteroids can be advised. As per your condition with no fever and slight whitish patches, it seems likely a viral one or fungal one as candidiasis ( common in old ages , immunocompromised)

You may also try following home remedies.
Get rest with sleep and rest your voice.
Do aspirin gargles.
Salt water gargles. I table spoon salt in one glass ( eight ounces ) of water.
HUmidify the air.
Consider throat lozenges.
Avoid irritants and allergens.
Take ibuprofen or tylenol for the fever if any.

I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards
Khan

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