Brief Answer:
In my opinion the sore throat, cold, common cold is the cause sir

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. I understand your cause for concern and would like to help by going ahead and listing all the causes for a salty taste in your mouth, they are:

+Dehydration
+Smoking
+Flu, common cold, post-nasal drip (which you seem to be having)
+Medical conditions (e.g. Sjogren's disease)

In my opinion your flu is most likely to be the cause for the salty taste in your mouth sir. The slightly sore throat and raspy voice also contributes to that assumption, and if this is a viral condition then your treatment will have to be symptomatic, but if at all it is a bacterial source then you will require antibiotic coverage. I would thus recommend a visit to your doctor for further management.

I hope you find my response helpful. Please feel free to write back to me for any further clarifications, I would be more than happy to help.

Best wishes.

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