RESUMO
Influenza A (H1N1) commonly known as swine flu, has covered a large part of the globe rapidly since the outbreak started in Mexico on 18th March, 2009. Given the rapid worldwide spread of the virus, it is important to identify the symptoms that require screening for influenza A(H1N1). Therefore, this study was planned to determine the clinical predictors of influenza A(H1N1) in the population of Kanpur city. Study sample comprised all cases with flu-like symptoms suspected of having influenza A(H1N1) whose nasopharyngeal samples had been sent for laboratory examination. Of the 119 samples sent to the laboratory, 34 were found to be positive for influenza A(H1N1). Best predictors found were fever with shortness of breath (positive predictive value=87.5%) followed by fever with cough without other cold like features (positive predictive value=68.6%). None of the clinical signs had all the attributes of a good predictor of influenza A(H1N1). Fever with cough was the most sensitive (70.6%) and fever with shortness of breath was the most specific indicator (98.8%). Therefore, it was concluded that symptoms like fever with cough without other cold like features and fever with shortness of breath should not be ignored and require expert medical attention for screening of influenza A(H1N1).
