Knowledge, Attitudes and Practices for Diagnosing Breakthrough Varicella in the Outpatient Setting

Background: Historically, varicella diagnosis was made clinically. After vaccine introduction, cases decreased dramatically and the proportion of previously immunized cases - breakthrough varicella (BV) - increased. Although milder than wild-type disease, BV is still contagious and easily confused with other rash illnesses, thus, diagnosis is unreliable without laboratory confirmation. Detection of varicella-zoster virus (VZV) DNA by polymerase chain reaction (PCR) from a skin lesion is the test of choice.

Objectives: To assess provider knowledge, attitudes and practices for BV management and to identify gaps in knowledge and barriers to implementation of VZV laboratory testing.

Methods: An in-person self-administered survey was given to health care workers (HCWs) in 30 large pediatric practices in Philadelphia, followed by a short educational session. The survey instrument collected information on clinicians’ practices relating to management of children presenting with rash, containment strategies, reporting to public health agencies, and laboratory testing.

Results: Among the 144 HCWs who completed the survey, 73 (51%) had practiced for >10 years. While 115 HCWs (80%) would elect to evaluate a child with rash in the office, only 19 (13%) would take specimens to rule in/out diagnoses. For patients known to be VZV exposed, 84 HCWs (58%) would use laboratory tests. For test method, 40% would use direct fluorescent antibody, 24% PCR from lesion specimen, 21% acute and convalescent serology, and 10% would use other tests. While waiting for test results, 82 (57%) would advise that the child be kept at home; 39 (27%) would notify the Health Department; and 33 (23%) would inform the school nurse.

Conclusions:As varicella becomes increasingly rare, similar to polio and measles, laboratory confirmation becomes more critical for appropriate diagnosis. Our findings suggest that healthcare providers need further education regarding the importance of laboratory confirmation, containment, and reporting of BV.