How does sinus infection affect the immune system? can sinus infection give you coldsores?

Sinus sores: Cold sores and sinus infections are both often triggered by viral infections. You may be mistaking a viral infection from a sinus infection.

Thanks for asking!: Any infection a person has can stress the body's immune system. The more severe the infection the more effect on the immune system. Herpes simplex viruses, which are present in the oral cavity, can cause cold sores with immune compromise or any form of minor oral trauma.

Complicated: The reasons that herpes simplex reactivates is not known, but almost any form of stress, whether emotional or physical may cause it in some individuals. Yes, sinus and other infections can result in cold sores, although they are not necessarily a direct cause.