There is a simple way to treat or prevent common cold and sore throat. Just gargle.
This is how:
Dissolve salt (mostly recommended) or vinegar or lemon juice in warm water and gargle.
You can use tap water. It contains chlorine and can clear the virus.
In people with sore throat, there is inflammation and edema of the mucosa. Salt, by osmosis draws water from the swollen area.
If you have a cold, gargling will relieve you of the discomfort.
Gargling also cleanses the throat.
This is how to gargle:
Fill your upper throat with the liquid and tilt your head upwards, making sure not to swallow.
Then expel air from your lungs to form bubbles throughout your throat.