This disease is caused by a virus called the JC (John Cunningham) virus. This is a common virus and most people probably are infected early in life. However, in people with HIV the virus can cause serious disease. The virus is possibly spread through sexual contact, or from mother to child.

Symptoms can include:

• difficulty in speaking
• difficulty in walking
• weakness in arms or legs
• personality changes
• seizures
• changes in vision
• headache
• shaky hands

There is no specific treatment for PML, but HIV therapy can reverse the symptoms and keep the JC virus under control. People with PML should have a good support system. Friends, roommates, or family members can help make sure that HIV medications are taken on time, in the right combination, and at the right dose. The disease is extremely serious and can lead to death.