Shingles usually develops when the dormant varicella-zoster virus becomes active again, causing fluid-filled blisters to form on the skin. It is also possible for a person to develop shingles after coming into contact with the fluid inside the blisters of an infected person, according to MedlinePlus.
Unlike many other viruses, shingles is not transmitted via coughing or sneezing. A shingles outbreak usually occurs in someone who previously had chickenpox. Although the chickenpox rash goes away, the virus responsible for the disease never leaves the body. In some people, the virus stays dormant forever. In others, the virus eventually becomes active again. This is what causes shingles, reports MedlinePlus.
Shingles cannot be spread by casual contact with an infected person. The only way to contract shingles from an infected person is to have direct contact with the fluid-filled blisters caused by the virus. Once the blisters crust over, the person is no longer contagious, states MedlinePlus. A person with shingles should keep the blisters covered to reduce the risk of transmitting the virus to others.
Getting vaccinated against shingles is the only way to reduce the risk of contracting the disease, according to the Centers for Disease Control. Although some people still get shingles after being vaccinated, the vaccine reduces the severity of the outbreak.