agnosis
Diagnosis is usually established clinically from the
characteristic rash which is easily differentiated from that of
small pox from the typical stages of development of the skin
lesions. Varicella–zoster specific IgM may be detectable as
early as 1-2 days before the appearance of the rash, although
the absence of antibodies does not rule out the diagnosis.6
IgG
antibodies appear shortly after the IgM response and persist
throughout lifetime6
. For fatal, severe or atypical illness the
Varicella zoster virus may be identified from skin scrapings by
PCR22 or by immunofluorescence techniques.2