Why does our voice change when we get affected by cold or cough?
The important point is that your voice is influenced by airflow, and your vocal cords. When we're sick, and it depends on what it is, a number of factors change the sound of your voice by influencing the two of these, either: By changing airflow due to respiratory tract swelling or fluid buildup, or by damage/swelling/alterations to the vocal cords. In a couple  of examples: A weak airflow might produce a higher pitch or weaker voice, or perhaps swollen vocal cords produce that hoarseness associated with decreased frequency of vibration.