From 2009, pandemic influenza A (H1N1) virus started to spread quickly over the world. It causes respiratory infection with signs and symptoms of common influenza like illness. Thus, clinicians sometimes may miss the patient who suffer from this disease. Human influenza A and B viruses are equally prevalent among human population. Mostly A virus genes evolve two to three times faster than the genes in B viruses. (Nobusawa and Sato, 2006). Laboratory tests are important for the diagnosis of the respiratory infection especially among paeds, elderly and immunocompromised patient. There are several tests available for influenza virus detection including rapid test, immunofluorescence technique, enzyme immunoassay and latest method is polymerase chain reaction (PCR). Nucleic acid amplification techniques based on reverse transcription polymerase chain reaction assays are regarded as a gold standard to confirm the influenza virus infection.(Kim and Poudel, 2013)
Nowadays, rapid influenza diagnostic tests that detect influenza viral antigens are used to screen patients with suspected influenza. The advantage of this method it give faster result within several minutes, compared with other method for influenza including immunofluorescence and PCR. That can improve the clinician making a decision. This method have also been used for public health purposes to investigate patient suspected influenza outbreaks. However, as a screening tests, the accuracy of rapid influenza tests is less than that of “gold standard” reference tests, such as viral culture and RT-PCR. (Uyeki et al., 2009).
Laboratory detection of influenza in elderly patients is a challenge for the diagnosis of respiratory infection due to the clinical presentation in these patients is often nonspecific and those patients may have a poor vaccine response. Therefore, the aim of this study was to evaluate the relationship between age with infection of influenza virus during returning from Mecca using high specific method for detection.(Perosa, Watanabe, Guatura, Silva, & Granato, 2009)