After chicken pox, VZV goes dormant in some nerve cells of the body; when it reactivates in a nerve, it causes symptoms, including pain and rash, along the path of that nerve, according to the Mayo Clinic.
Because shingles symptoms appear along the path of a nerve, they are usually limited to one side of the body, reports the National Library of Medicine's MedlinePlus website.
The sites most commonly affected by shingles outbreak include, says MedlinePlus, the trunk of the body or the head, including the face.
Disseminated shingles, which are in more than one place, may occur in people who are immunocompromised (with weakened immune systems), according to MedlinePlus.
If pain and rash occur in more than one place on the body, it is generally an indication that shingles is not the cause, and further testing may be necessary.