Prevalence and seasonality of influenza virus among pediatric population in Nepal, 2018

Abstract

Background: Influenza is one of the emerging cause of acute respiratory infection in children. Very limited information's are available on influenza morbidity and mortality in Nepal. The aim of this study was to determine the prevalence and seasonality of Influenza virus in children (below 5 years) in Nepal. Methods and materials: This was a descriptive study conducted at National Influenza Center, Nepal. A total of 424 throat swab samples were collected from children with influenza like illness from January to December 2018. Total viral RNA was extracted using mini RNA extraction kit (Qiagen, USA) and real time PCR amplification was performed according to US, CDC test protocol. Results: Out of 424 samples, 62 (14.6) samples were positive for influenza virus. Of the total, influenza type A and B were 33 (53.2%) and 29 (47%), respectively. The rate of influenza B virus infection was found higher 29 (46.8%) followed by influenza A subtype A/H3 24 (39%) and A/H1N1 pdm09 9 (14%) during the year 2018. A total of 43 (10%) samples were from SARI case, of which 12 (28%) were influenza positive. Out of 381 (90%) ILI samples, 50 (13%) samples were influenza positive. Influenza was observed year-round in Nepal, however; peak activity was found in winter season (January–March), 2018. Conclusion: Transmission of influenza virus was found year round in Nepal which was similar to subtropical countries of south-east Asia. Hence, influenza diagnostic facilities need to be expanded for timely diagnosis, pandemic preparedness and response.