A nursing student received 2 valid, documented doses of varicella vaccine. For whatever reason, she subsequently had a titer drawn. The titer was negative. Do you recommend revaccination with 2 doses of varicella vaccine?

No. Documented receipt of 2 doses of varicella vaccine supersedes results of subsequent serologic testing. Most commercially available tests for varicella antibody are not sensitive enough to detect vaccine-induced antibody, which is why CDC does not recommend post-vaccination testing. For more information, see page 24 of ACIP’s Immunization of Health-Care Personnel, available at www.cdc.gov/mmwr/pdf/rr/rr6007.pdf.