The 2018-19 influenza season in Afghanistan: Epidemiology and Virology

Abstract

Objective This paper aims to provide information on epidemiology and virology of seasonal influenza for the 2018-19 season, and build upon limited information for developing influenza vaccination policy for risk groups in Afghanistan. Methods This paper is based on a retrospective analysis of Afghanistan influenza surveillance data, both from influenza-like illness (ILI) and severe acute respiratory infection (SARI) cases during the 2018-19 season. The data for 2018-19 has also been compared to the data of the previous two seasons (2016-2017 and 2017-2018). Results During the 2018-19 season, a total number of 10,604 ILI and 5,261 SARI cases were reported to the national influenza sentinel surveillance system. From week 48 2018 to week 14 2019, a total of 713 ILI specimens were tested for influenza virus, and 10.7% were positive with majority influenza A(H1N1)pdm09 virus (57%). Similarly, a total of 1,004 SARI specimens were tested for influenza virus during this period, and 11% were positive for influenza with the majority caused by influenza A(H1N1) pdm09. Almost two-thirds (62%) of the ILI-influenza positive cases and 46% SARI-influenza positive cases aged less than five years. Also, over 50 years old patient was reported to have the second-highest proportion of SARI associated influenza (30%). Conclusion The findings indicate that the seasonal influenza virus results in considerable hospital visits, admissions, and deaths in Afghanistan. The data from this study will inform and guide policymakers in developing national influenza vaccination policies.