Report on Influenza A and B Viruses: Their Coinfection in a Saudi Leukemia Patient

PURPOSE Influenza A and B viruses are the leading cause of respiratory infections in children worldwide, particularly in developing countries. There is a lack of data on coinfection of influenza A and B viruses circulating in Saudi Arabia. In this study, we aimed to identify the circulation of influenza viruses that contribute to respiratory tract infections in Saudi children. METHODS We collected 80 nasopharyngeal aspirates (NPAs) from hospitalized children with acute respiratory illness (ARI) at Riyadh during the period extended from October 2010 till April 2011. Samples were tested for the common respiratory viruses including influenza viruses by RT-PCR. RESULTS Overall, 6 samples were found positive for influenza A and/or B viruses. Among these positive clinical samples, only one collected sample from a female one-year-old immunocompromised child with leukemia showed a coinfection with influenza A and B viruses. In present study coinfection was confirmed by inoculation of the clinical specimen in specific pathogenfree embryonating chicken eggs and identification of the virus isolates by hemagglutination and one-step RT-PCR. CONCLUSION This study opens the scene for studying the role of influenza virus's coinfection in disease severity and virus evolution. Further studies are required to better understand the clinical importance of viral coinfection.