Shingles is a viral infection caused by the varicella-zoster virus that most commonly affects people over the age of 50, according to FamilyDoctor.org. This infection is a complication of chicken pox that can cause severely painful skin symptoms, such as rash or blisters. People over the age of 60 can help reduce their risk of developing shingles by receiving the shingles or herpes zoster vaccine. A doctor should discuss shingles vaccine warnings with all patients before immunization.
Allergy or Pregnancy
This injection should not be administered to people with a known allergy to neomycin, gelatin or any other component of the shingles vaccine, according to Merck, the pharmaceutical distributor of the vaccine. Improper treatment of this patient population can increase the risk of severe, life-threatening allergic reaction symptoms. Doctors are warned that appropriate allergic reaction treatments, such as epinephrine injection, should be readily available if a severe allergic reaction occurs.
Women who are pregnant or may become pregnant should also not receive the shingles vaccine. The safety and effectiveness of the shingles vaccine has not been clinically evaluated in pregnant or nursing mothers and may negatively affect fetal or infant development.
Concurrent Infection or Illness
People who have a compromised immune system due to disease or disease treatment should not receive the shingles vaccine. Lymphatic diseases, such as lymphoma or leukemia, and AIDS can interfere with the body's ability to fight off infection. Cancer therapy treatment, including chemotherapy and radiation, can also decrease the number of immune cells the body has available to protect itself against pathogenic invaders. People with these types of pre-existing medical complications are at an increased risk of developing shingles after receiving the shingles vaccine, according to the Centers for Disease Control and Prevention.
Vaccine Effectiveness
Health professionals with Merck warn that it is unknown whether the shingles vaccine remains effective for longer than four years after initial treatment. Consequently, people treated with this vaccine may still be susceptible to developing shingles later in life.
Side Effects
Side effects can occur in certain people that receive the shingles vaccine. Approximately one in three people develop injection site reactions, which include pain, swelling, redness or itching of the skin, the CDC says. Certain people can also experience a mild to moderate headache. These side effects of the shingles vaccine are temporary and typically resolve within a day or two of treatment.
