Tzanck Test Do You Know What It Is?

The Tzanck test is a method of testing sores for the herpes simplex virus (which causes cold sores, fever blister, or genital sores), or varicella-zoster virus (which causes chickenpox and "shingles").


The test in performed by the sore is scraped and the scraping is put on a slide and stained. The health care provider then examines it under a microscope.

When the sore is scraped or rubbed, there may be mild discomfort.

The test may help diagnose or confirm an infection with 1 of these 2 viruses.

This test can not distinguish between these two viruses.

The results are immediately available. If herpes-infected cells are detected, the patient has been infected with one or the other of the following:

Herpes simplex (which causes cold sores, fever blister, or genital sores)
Varicella-zoster virus (which causes chickenpox and "shingles").

There are no risks with this test.

There is a high rate of false-negative results even when the virus is present.