Work

Sampling and Host–Strain Interactions Shape Detection of Staphylococcus aureus Transmission in Hospitals

Year: 2026

Type: article

Abstract: BACKGROUND: In principle, whole-genome sequencing of Staphylococcus aureus in hospitals is most effective when used prospectively, but its practical limits are unclear. METHODS: We performed large-scale genomic surveillance across 2 interconnected hospitals, sequencing 4779 S. aureus isolates from admission screening and clinical cultures. Integration of genomic and epidemiologic data identified 361 transmission events undetected by standard surveillance. RESULTS: Despite dense sampling, most events (90%) were detected only at readmission, indicating that transmission escapes recognition during the index hospitalization. Serial or discharge screening is likely required to capture transmission. Detection depended on sampling: clinical isolates alone were insufficient, and nearly all events required screening and repeated sampling. CONCLUSIONS: Because such approaches are unlikely to scale if applied universally, surveillance must be targeted. Transmission concentrated in methicillin-resistant strains, and it increased when healthcare exposure coincided with hospital-associated strain lineage. These findings help define the limits of prospective genomic surveillance and provide a framework for targeted detection.

Source: The Journal of Infectious Diseases

DOI: 10.1093/infdis/jiag361