Does having a small open wound like canker sore or gigivitis inside your mouth increase chances of catching influenza?

Risk factors: While the answer to your question might technically be yes, other risk factors such as age, general health, many medical conditions, quality of your immune system, working/living conditions, general hygiene, good nutrition and enough sleep play a much more significant role.

Immune system : Mouth heals much faster then the rest of your body. Catching influenza depends on the ability of your immune system to resist the viral challenge. The fact that you may have a canker sore can signify that your body’s immune system is challenged already and getting influenza may be more likely. Therefore a good routine, healthy diet, exercise and quality sleep will aid to body’s regeneration.