Shingles

Caused by reactivation of VZV (same virus as chicken pox), with characteristic painful rash in a dermatomal pattern.

Vaccination is funded in NZ in those aged 65 years. This is regardless of whether they recall a history of chicken pox, and serology to check is not recommended.

• Laboratory testing is not usually required. The diagnosis is made clinically in the vast majority of people due to the characteristic nature of the rash.
• Laboratory testing is reserved for atypical cases where there is diagnostic uncertainty.
• We recommend HIV testing in people with recurrent or atypical presentations of shingles, including shingles occurring in young people.

Request VZV PCR

Viral swab of rash for VZV PCR (need to obtain fluid or cellular material on swab)

• Good sensitivity – a negative result on an adequately collected sample makes the diagnosis very unlikely
• Excellent specificity – a positive result confirms the diagnosis

Note: swabs run for VZV PCR in our laboratory are run for HSV PCR in parallel, as these viruses can mimic each other.

Serology

This has no role in the diagnosis of shingles due to the fact shingles is caused by reactivation of a virus already present in the body.