Once a person becomes infected with the varicella-zoster virus, it never fully goes away. Instead, after chickenpox clears up, the virus goes dormant in some nerve cells of the body.
It is not fully understood exactly why shingles occurs when it does, although the Mayo Clinic reports that risk factors include aging and having a weakened immune system.
After a first outbreak of shingles, the varicella-zoster virus goes dormant again, just as it does after chickenpox. This means that further outbreaks are possible.
The shingles vaccine can help reduce the chances of a shingles outbreak, even in people who have already had one outbreak, according to the Centers for Disease Control and Prevention.
Although the shingles vaccine has been reported by the CDC to lower the risks of developing shingles, including a recurrence of the condition, it is not 100 percent effective in preventing in shingles outbreak.