Epidemiology and Molecular Characterization of Seasonal Influenza Viruses in Iraq

The importance of influenza viruses in respiratory infections in the Middle East, including Iraq, has been historically overlooked. Nowadays, with the pandemic of corona virus disease 2019, the importance of prevention from other respiratory diseases, such as seasonal influenza, can be a critical step in the health management system. Therefore, this study aimed to evaluate the prevalence and seasonal occurrence of influenza viruses in the Iraqi population presented with influenza-like illness (ILI) or severe acute respiratory infection (SARI)within2015-2017. Moreover, this study was conducted to identify the periods with increased influenza transmission for vaccination recommendations in Iraq. In the present study, we presented the cases of infection by influenza A or B viruses. To test influenza virus types A (H1N1 and H3N2) and B, 1,359 throat and nasal swabs were collected from patients with ILI or SARI. Ribonucleic acid was extracted and amplified using a set of primers and probes. The frequency rates of infection were obtained at 1,616 (45%) and 1974 (55%) in females and males, respectively. The mean age of the participants was estimated at 31.71±22.68 with a minimum and maximum ages of 1 month and 96 years, respectively. It was revealed that influenza virus type A was the most predominant with an incidence of 16.2%, followed by type B with 0.33% incidence. It was also found that December was the most prevalent month of being infected by influenza viruses types A and B (30.02% and 0.48%, respectively). Vaccination in September would likely protect the highest number of patients. It was clear that the influenza A virus was predominant over type B. In Iraq, influenza A and B viruses were found in a large percentage of ILI and SARI cases. Additionally, males were reported to be more likely to become infected than females.