Advances in treating opportunistic infections can happen at any time, so the material on this page may be outdated. Some links in the see also section at the bottom of this page are actually special database links. They may contain information published after this page was written.
Some researchers suggest that infection probably occured during childhood.
PML isn't considered contagious. Symptoms include speech problems, weakness in one side of the body, loss of vision in one eye, numbness in one arm or leg. Once PML begins, it is usually quite aggressive and fatal. Several experimental therapies are being worked on. This information is designed to support, not replace, the relationship that exists between you and your doctor.