Asking Questions Influences Serology Testing Patterns

Online survey notes rate of serology testing remain high in Canada, even when vaccination history is known.

SAN DIEGO — Asking an expectant mother about their current vaccination status, as it relates to varicella, hepatitis B and rubella vaccines, often influences what serology tests a clinician will request. 

Michael Desjardins, PhD, an infectious disease fellow based in Montreal, Quebec, told an Infectious Disease Advisor reporter, “when we ask for vaccination history, we can order less tests.” 

Dr Desjardins presented data from an online practice survey of 363 clinicians, including 142 general practitioners, 98 obstetrician-gynecologists, 77 midwives,  and 46 nurse practitioners, which showed that only about half of clinicians asked about vaccination status as it relates to hepatitis B and rubella. Even in those patients on whom a history was obtained, a large number of serology tests were ordered, as high as 44% for women who had been vaccinated against rubella. 

Varicella zoster infection was discussed by just over 80% of the respondents, the researchers said, “with 13% reporting ordering serology testing with a history of VZV infection, compared with 87% in those patients whose history was “uncertain,” and 19% in those patients with a history of vaccination. 

Dr Desjardins called those numbers – particularly the number of serology tests ordered in women with a known rubella vaccination status – “a little high,” and explained that clarity of guidelines as they related to Canada – likely are needed on when to order serology when vaccination history is known.  


  1. Desjardins M. Poster I-299. Presented at: ICAAC/ICC 2015; Sept. 17-21, 2015; San Diego.