Serratia marcescens multiclone outbreaks in a tertiary hospital in India

We report the use of Next Generation Sequencing (NGS) technology for understanding an outbreak of 13 cases of Serratia marcescens blood stream infections in various wards in a tertiary care hospital in India over a 5 month period. Antibiogram based typing was inadequate to trace the source of infection in contrast to NGS data analysis with its significantly higher resolution. This outgreak investigation shows that polyclonal outbreaks can occur in a hospital simultaneously. Extensive surveillance of environment helped improve infection control practices in compounding pharmacy.