Genomics of Golden Staph: Discovering genomic markers of transmission of Staphylococcus aureus

Abstract

Staphylococcus aureus is an important, predominantly human pathogen with a high burden of disease. S. aureus infections result in significant morbidity and mortality globally, owing in part to the wide spectrum of diseases which can be attributed to the pathogen (Tong et al., 2015).

The significant burden of S. aureus diseases across the community necessitates the development of tools for epidemiological investigations and a variety of infection control interventions, particularly within the healthcare setting (Dufkova et al., 2022). Bacterial subtyping is well established as an epidemiological tool and can be used in epidemiological investigations to determine details of microbial transmission (Sandora et al., 2014).

Epidemiological investigations and typing efforts to date, largely focus on MRSA, where incidence rates of around 10 per 1000 hospital admissions are reported from whole of hospital studies (Al-Talib et al., 2010). Binary typing of MRSA by multiplex PCR reverse line blot assay (mPCR/RLB) was previously developed (O'Sullivan et al., 2012).

In this thesis, targets were selected as the first step in developing a binary typing assay for methicillin-sensitive Staphylococcus aureus. An mPCR/RLB assay was then developed for use in prospective typing studies of MSSA. Subsequently, the assay has been employed in three different healthcare and community settings. Namely, in the typing of methicillin-sensitive S. aureus (MSSA) causing bloodstream infections in New South Wales; in typing MSSA responsible for both infection and colonisation from all sources at a single healthcare facility; and amongst players from a professional sporting team amidst an outbreak of skin and soft tissue infection.