A clinical utility of a strip test for influenza A/B and comparison with detection by RT PCR.

Abstract

In June 2009 the World Health Organization announced influenza pandemic caused by A/H1N1/v virus. It became crucial to recognize new cases of A/H1N1/v infection. An effective screening diagnostic procedure was needed for patients suffering from influenza-like symptoms for making an initial diagnosis and analyzing epidemiological pattern of infection. We used a strip test for influenza A/B as a screening diagnostic procedure for patients suffering from influenza-like symptoms for making an initial diagnosis. For comparison, RT PCR for detecting A/H1N1/v was performed. The aim of this study was to assess the efficacy and sensitivity of the strip test and its value for making initial diagnosis of influenza A/H1N1/v. Strip testing for the influenza A/B infection was performed on 1123 patients with influenza-like symptoms in the Admission Unit of the Regional Infectious Diseases Hospital in Warsaw. Strip test results were analyzed according to the age of patients and season of the year. For 97 patients strip test results for detecting A/H1N1 infection were compared with those obtained by RT PCR. There were no statistically significant differences found between the methods and strip testing demonstrated sensitivity of 61% and specificity of 71%. No statistically significant differences were found between the two methods, however, strip test had low sensitivity and specificity.