What Causes Severe Itching Sensation On The Testicles?
Possible fungal infection.
Detailed Answer:
It's hard to tell from the picture exactly what is going on but it looks like the skin is generally irritated/inflamed. The skin of the scrotum can get a fungal infection which is usually tinea cruris (also called "jock itch"). It is itchy and can wax and wane.
Treatment is an anti fungal cream such as clotrimazole (Lotrimin cream) which you can get without a prescription. It is applied to the affected area and a little bit of the surrounding unaffected area, to clean dry skin. This needs to be done twice a day for 14 days.
If either there is no improvement in 14 days or if it gets significantly worse, then do go in to see a doctor in person.
Try to keep the area as dry as possible, such as by wearing cotton boxer shorts.
I hope this information helps.
Fungal infections can definitely spread.
Detailed Answer:
Fungal infections can spread. Use the clotrimazole (Lotrimin) or terbinafine (Lamisil) wherever you see the rash, but if the rash is extensive, do go in to see your doctor.
Try to support your immune system with good sleep, healthy food, and not much alcohol so that the medicine and your immune system resolve the rash quickly.