Time Trend of Swine Flu at a Tertiary Care Centre of Western Rajasthan: A Decadal Analysis

Abstract

Background: Swine flu had been established as seasonal influenza, but antigenic variation continues to result in epidemics that necessitate continued surveillance. Present study aims to describe the time trend of swine flu from its initiation in 2009 to 2019 from western zone of Rajasthan. Material and Methods: This secondary analysis of swine flu data from established seasonal disease reporting was conducted at a tertiary care centre of western Rajasthan which was the only swine flu testing centre in this area. Only Lab confirmed cases from this centre were included for month wise distribution. Results: First case from Jodhpur was seen in August 2009. Large peaked outbreaks were seen around every 4 years namely 2009-10, 2014-15, 2018-19 corresponding to the antigenic variation of this virus namely California, Michigan and Brisbane strain respectively. Cases were seen in mostly in winters with peak in December/January. Mortality rate among these lab confirmed cases varied from 0–22% in different outbreaks. Conclusion: Continued laboratory surveillance is necessary to identify the time pattern of outbreaks and for early identification of emergence of new strain to ensure early and timely preparedness for impending epidemics.

Keywords

• Swine flu
• influenza
• outbreak
• epidemic
• pandemic