Anti-VZV
The varicella zoster virus (VZV) causes chicken pox and shingles (herpes zoster) and belongs to the family of human pathogenic alpha herpes viruses. After an incubation period of two weeks, patients develop a fever and the typical, itchy chicken pox rash. The infection is usually self-limiting. Herpes zoster is caused by reactivation of the virus, which persists in the ganglia of spinal and cranial nerves. Primary infection with VZV before the twentieth week of pregnancy may cause harm to the unborn child. Neonatal chicken pox infection may also be quite severe. Chicken pox and shingles are usually diagnosed on the basis of clinical symptoms. In cases of complications or infection during pregnancy, serological diagnostics become important. If VZV infection is suspected, IgG, IgM, and IgA antibodies should be tested. IgM antibodies are typical of the acute phase of infection. They are absent or very scarce upon reactivation of the virus (herpes zoster). In such cases, increasing titres of IgA and IgG antibodies are more diagnostically informative. IgG determination is used for documentation of immune status and to confirm successful immunization. The ORGENTEC Anti-VZV IgA and Anti-VZV IgG tests for Alegria® use VZV glycoproteins isolated from virus cell cultures as antigens. Anti-VZV IgG is calibrated against the international WHO reference preparation (NIBSC code W1044). Recombinant glycoprotein E is the antigen in the Anti-VZV IgM Abs. test.