Prevalence of Influenza A/H1N1 Virus in North of Iran, 2013 to 2017

Background and purpose: Influenza viruses annually spread around the world in seasonal epidemics. The A/H1N1 virus causes more severe conditions compared to other types of Influenza A. This study is an epidemiological survey of influenza A/H1N1 virus in patients attending health care centers in north of Iran during 2013-2017. Materials and methods: Sampling was done in 3037 patients. Influenza-RNA was extracted from the samples using Viral RNA/DNA Kit PureLinkTM. Identification of influenza A/H1N1 virus was done using special primers and probes (Invitrogen), and Quantitative Real Time PCR System (SuperScript III Platinum). Results: The samples were obtained from both males (39.9%) and females (60.1%). Patients aged 31-40 years of old included the majority of samples. Influenza A/H1N1 positive samples were seen more in patients aged 61-70 (18.51%) (14.55%). Out of the 442 confirmed cases of influenza A/H1N1, 23 (5.88%) deaths were reported. Conclusion: Influenza A virus is constantly evolving by mutation or by reassortment. It evolves rapidly, and new strains quickly replace the older ones, therefore, new vaccines should be developed for immunization against new strains of influenza.