Varicella (Herpes)Zoster IgG Antibodies

Over the last few decades, there has been a massive rise in the number of cases of Varicella Zoster infections. This makes the Varicella Zoster IgG blood test important to detect Varicella Zoster IgG levels and make sure patients can fight the infection. Varicella Zoster virus (VZV), also known as HHV-3, is the causative agent for the highly infectious condition chickenpox. This is a disease seen across the world. Chickenpox infection causes an itchy, red rash that spreads over the entire body. It also shows the presence of small fluid-filled lesions that later burst. Most children experience an episode of chickenpox early on. The symptoms are self-limiting and resolve within 10 days. Once the lesions are crusted, they are no longer infectious. In rare cases, it can progress to a more severe disease. Herpes Zoster infection or shingles are also caused by VZV. This happens because VZV can remain in the nerves of the body in an inactivated state. Its reactivation results in shingles. This condition does not spread from one person to another. However, it is possible for a person with no VZV antibodies to develop chickenpox after contact with an active case of shingles. Hence, Varicella antibodies provide protection against VZV infections. When a person is infected with VZV, an immune response is stimulated in the body. This immune response involves the production of antibodies. Two types of antibodies are involved. Immunoglobulin M or IgM is increased in the acute phase when there is a recent infection. Immunoglobulin G or IgG is increased in the resolving phase of the infection. The Varicella Zoster vaccine is available in India. It is not a part of the compulsory schedule. However, it is often administered in childhood or elderly patients. Two doses of the vaccine are given to children over one year of age. This ensures that even if the infection occurs, it is generally mild with fewer lesions. After vaccination, the levels of antibodies increase. The Varicella Zoster IgG test helps detect if the antibodies are sufficient to fight infection. As VZV causes a contagious(spread easily) infection, it is important to diagnose it early. It has an infectivity rate of almost 90%. This means almost every person in contact with an active case is likely to develop the disease. A large bulk of the cases are in the elderly population, especially those who are immunosuppressed. In these patients, it is important to check for Varicella Zoster IgG antibodies to ensure that the body has the ability to fight the infection.