Serological testing for immunity to varicella is not recommended before or after receiving varicella-containing vaccine

Children

In children, testing to assess serological status before vaccination is generally not recommended.

If there are no contraindications, children can safely receive either varicella or MMRV vaccine, even if they have previously had varicella infection. See Children aged <14 years.

Children should receive varicella-containing vaccine if they have either:

• an uncertain clinical history of varicella infection, or
• no documentation of age-appropriate varicella vaccination

In young children, a reliable history of varicella infection correlates highly with serological evidence of immunity.^12,13 If there is not a confident clinical diagnosis of previous infection, children should receive varicella-containing vaccine. This is because the incidence of varicella is decreasing in Australia, and people may be less familiar with the disease.

Older adolescents and adults

Serological testing before varicella vaccination may be helpful in older adolescents and adults who have:

• a history of no previous varicella infection
• no documentation of age-appropriate varicella vaccination

Most people with a history of no varicella infection are immune, and may not need vaccination^.14,15

When interpreting serological testing results, it may be useful to discuss the results with the laboratory that performed the test, to ensure that decisions are based on all relevant clinical information.

Women planning pregnancy

Women who are planning pregnancy or pregnant are recommended to receive screening for varicella immunity (from natural infection) or a history of vaccination.

Non-immune women are recommended to receive varicella vaccine before they become pregnant.

When interpreting serological testing results, it may be useful to discuss the results with the laboratory that performed the test, to ensure that decisions are based on all relevant clinical information.

Serological testing after varicella vaccination

Testing for seroconversion after varicella vaccination is not recommended.

Antibody levels after vaccination may be up to 10-fold lower than levels induced by natural infection.^10,16,17 Commercially available laboratory tests are not usually sensitive enough to detect these levels.

Assume that a child or adult is protected if they have documented evidence that they received age-appropriate dose(s) of varicella-containing vaccine.