Sweat patches are not contagious.
Sweat patches are a fungal superficial inflammation due to the involvement of Malassezia in the stratum corneum of the skin. Although sweat patches are fungal infections, they are conditionally pathogenic because Malassezia exists in everyone’s skin and will only become infected and form sweat patches when conditions allow.
There are many reasons causing conditional infection, the first one is genetic factor; the second one is the reason of hot weather and large amount of sweating; in addition, it has relationship with the patient’s physique and immunity, and it is easy to trigger infection when the physique and immunity are declined.
The treatment of sweat spots is based on topical antifungal drugs, commonly used drugs are terbinafine cream, ketoconazole cream and so on.