A positive history of varicella (chickenpox) has high positive predictive value

  • Holmes CN


When somebody reports a past history of varicella, does it mean he/she already had varicella (and therefore immune)? Similarly, when he/she says no, does it really mean she never had varicella (and therefore susceptible to this infection)? These questions occur not infrequently in clinical practice and have assumed increasing relevance with the availability of varicella immunisation. In a systematic review of published cross-sectional studies comparing history of varicella and varicella-zoster virus serology, Holmes reported these findings: positive predictive values (PPV) 95-98.5%, negative predictive values (NPV) 6-44%. The results show that a positive history of varicella is almost always correct but a negative history of varicella is inaccurate (most of them actually had varicella). It is noteworthy that all the 12 studies evaluated by Holmes were conducted in the developed countries (USA, Canada, Australia, Ireland), we need to bear in mind that the problem of late seroconversion in tropical countries (i.e. more adults who have never had varicella) and lack of accuracy of past history in patients with low literacy. (copied from article)
How to Cite
CNH. (2012). A positive history of varicella (chickenpox) has high positive predictive value. Malaysian Family Physician, 13(3), 1. Retrieved from https://www.e-mfp.org/ojs3/index.php/MFP/article/view/152
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