Emergence of Elizabethkingia anophelis. First case of E. anophelis outbreak in a neonatal unit of a hospital in Argentina

Abstract

• Elizabethkingia anophelis is a newly-discovered bacterium. • Several investigators have demonstrated an association of clinical isolates with environmental isolates. • Could not be accurately identified using traditional biochemical-based phenotyping methods. • MALDI-TOF is a fundamental tool for the rapid identification of these microorganisms. • The rapid identification of a patient colonized is essential in the surveillance system. • The whole genome sequencing allowed confirmation of the outbreak. This article describes an outbreak of E. anophelis in a neonatal unit in a private hospital in Buenos Aires, Argentina, in which the source of infection was identified, therefore allowing the prompt intervention of the infection control team. The awareness of E. anophelis infections and the collaboration between infection control teams and microbiologists in order to control these hospital outbreaks are of great relevance. Nine clinical isolates in neonatal unit obtained from rectal swabs (6), blood (2) and respiratory samples (1) were evaluated from July to September 2020. MALDI-TOF (BD-Bruker Daltonics) was used for the identification (Table 1), and minimal inhibitory concentrations (MICs) were determined by the Phoenix method (Becton, Dickinson) and by the epsilometer method (MIC Test Strip, Liofilmchem). Whole genome sequence analysis was performed on a MiSeq instrument using the Nextera XT DNA library preparation kit (Illumina, Inc., San Diego, CA, USA). Environmental samples were also collected from faucets and sink located in clinical areas. All isolates identified as Elizabethkingia anophelis by MALDITOF-MS, Biotyer 3.1 (Bruker) were confirmed by 16SrARN and rpoB sequencing. One isolate identified as E. anophelis was cultured from one faucet aerator. Out of 9 clinical isolates, 8 were genetically related, as was the case with the environmental isolate. The rapid identification of a patient colonized is essential in the surveillance system. E. anophelis have a high mortality rate due to the delay in the administration of the appropriate treatment. Our study is a report of an acute E. anophelis outbreak in a neonatal unit in Argentina, in which the source of infection was identified, therefore allowing the prompt intervention of the infection control team.