A scoring system for predicting results of influenza rapid test in children: A possible model facing overwhelming pandemic infection

BackgroundThe pandemic novel influenza H1N1 (swine) influenza A virus (H1N1v) infection has caused large-scale community infection in Taiwan. Anxiety developed in the general public and physicians faced a huge challenge in many aspects. We conducted this prospective study to develop a scoring system based on the clinical manifestations for predicting the results of influenza rapid testing, as a surrogate of influenza rapid testing, to lower the anxiety and decrease the burden for the test.MethodsFrom September 1, 2009 to October 5, 2009, pediatric patients who received influenza rapid tests were enrolled, and questionnaires were recorded and analyzed in the first 2 weeks. A further scoring system was conducted to predict the results of influenza rapid tests and validated in the next 3 weeks.ResultsEight hundred and forty-five children were enrolled in our study. In the first phase, data from 506 patients showed that those with age ≥ 5 years, fever ≥ 38°C, contact history of influenza A infection, myalgia, lethargy, sore throat, cough, and headache had a higher risk of positive results (odds ratio: 1.1–2.53). A scoring system was designed, with ≥5 points indicating acceptable sensitivity (69.5%) and specificity (63.6%). Three hundred and thirty-nine patients in the second phase were enrolled to validate the scoring system and the positive and negative predictive values were 52.0% and 73.8%.ConclusionThe emergence of H1N1v infection is not only an important medical issue, but also a socioeconomic problem. Based on easily available clinical information, we develop a scoring system as a preliminary screening tool for the general public and first-line health care providers to evaluate the possibility of influenza virus infection. Although this study was limited by the sensitivity of rapid tests, this type of model may be a surrogate weapon when faced with overwhelming pandemic infection in the future, especially in areas with scarce medical resources.