Performance of QuickVueŽ rapid influenza testing during the H1N1 pandemic

Background:

The World Health Organization (WHO) designated June 11 as the onset of the 2009 novel H1N1 Influenza pandemic. With increased demand for testing, we anticipated the need for a rapid testing method to detect Influenza A. The QuickVueŽ kit claims 94% sensitivity, 90%specificity, a PPV of 62 % and NPV 99% for routine seasonal Influenza A. We sought to compare this method with Direct Fluorescent antibody technique (DFA) and viral culture to evaluate sensitivity and specificity for the novel H1N1.

Methods:

Results from all nasal swab samples submitted for Influenza testing in the Emergency Department (ED) between March 1 and June 30, 2009 were collected.

Specimens submitted for simultaneous Influenza assays were analyzed.

Results:

A total of 1183 samples were collected. Rapid Influenza testing, DFA and Viral culture were available for comparison in 153 samples.

Based on usage by multiple ED providers, the sensitivity of the rapid test was 73%; specificity 85%, PPV was 75 % and NPV 84% in relation to the other assays.

Discussion

The QuickvueŽ kit compares favorably to itself in the face of the H1N1 subtype and is an effective rapid detection method for use in the ED.

Comparison to specific assays for H1N1 will be needed to further determine the testing reliability in the ambulatory setting.