399. Recent COVID-19 infection is associated with high risk of mortality among patients with Staphylococcus aureus bacteremia

BACKGROUND: Staphylococcus aureus bacteremia (SAB) is associated with significant mortality. Recent reports indicate that the incidence of invasive S. aureus infections has increased since the start of the COVID-19 pandemic. The impact of recent COVID-19 infection on clinical outcomes of patients with SAB is unknown. METHODS: We performed a retrospective study investigating outcomes associated with SAB in patients with recent COVID-19 infection (SAB-C) versus patients with SAB without a recent positive COVID-19 test (SAB-N). We used data collected by the Georgia Emerging Infections Program (EIP), a CDC- funded invasive S. aureus surveillance study in the 8-county Atlanta metro area to identify all patients with SAB between 2020-2021. SAB cases were linked to COVID-19 test results from the Georgia Notifiable Disease Reporting data to collect patient COVID-19 test results within 90-days of the initial positive blood culture. For subjects experiencing > 1 episode of SAB, only the first episode was evaluated to ensure independence of observations. Comparisons were made using Kruskal-Wallis test and Fisher’s exact test as appropriate. Statistical significance was set at P=0.05. RESULTS: Between 2020 -2021 there were a total of 3705 unique patients with SAB. Among them, N=486 (13.1%) had a positive COVID-19 test <90 days prior to SAB (SAB-C), and N=3219 (86.9%) did not (SAB-N) (Table 1). Median time from positive COVID-19 test to first positive blood culture was 7 days. SAB-C had a greater proportion of methicillin resistant S. aureus (MRSA) and hospital onset infection than SAB-N (41.8% vs 36.1%, p=0.0189, and 45.7% vs 17.3%, p< 0.0001 respectively). 7-day mortality and in-hospital mortality were significantly higher among SAB-C vs SAB-N (25.7% vs 9.0%, p< 0.0001, and 43.6% vs 15.3%, p< 0.0001, respectively). Among SAB-C, hospital onset of SAB was significantly associated with mortality (29.6% survivors vs 66.5% non-survivors, p< 0.0001, Table 2). [Figure: see text] [Figure: see text] CONCLUSION: SAB-C is associated with high mortality. Further research is needed to understand additional factors contributing to this high mortality rate including source of infection, infecting strain, and underlying host immune factors. DISCLOSURES: All Authors: No reported disclosures