Varicella Zoster IgG
Varicella Zoster is another name for the virus which causes chickenpox and shingles. It is a type of herpes virus and tends to infect a large proportion of the population at a young age, causing chicken pox, and from there on it lays dormant in the nerve cells. However, in about 25% of people, the virus may reactivate later in life, presenting itself as shingles, a painful blistering rash focussed on one particular area of the body.
Testing for the presence of IgG in the blood indicates whether someone has previously been infected and has developed immunity to the virus.
What might a low result mean?
No sign of IgG in the blood indicates no previous infection with the virus. This means that, when coming into contact with another individual who has chickenpox, the person is susceptible to catching it and also developing chickenpox.
What might a high result mean?
The presence of IgG in the blood indicates previous infection with the virus. This is because, a while after a viral infection develops in the body, the immune system produces a specific antibody, known as IgG, to protect the body from being infected again by coming into contact with another person infected with chickenpox.
IgG does not however prevent the reactivation of the virus as shingles.