The Varicella Zoster Virus (VZV) IgM test is a diagnostic tool used to detect the presence of IgM antibodies specific to the VZV in a patient’s blood. VZV is a highly contagious virus that causes two common diseases, chickenpox and shingles. The IgM antibodies are produced by the immune system in response to an active VZV infection. The test is performed by taking a blood sample from the patient, and the results can be used to confirm or rule out a current VZV infection. A positive result indicates an active infection, while a negative result suggests the absence of an ongoing infection. It is important to note that the IgM test cannot distinguish between a recent or past VZV infection, and therefore it is often used in conjunction with other diagnostic tests to obtain a more accurate diagnosis.