Methicillin-resistant Staphylococcus aureus lung infection in coronavirus disease 2019: how common?

PURPOSE OF REVIEW: Some patients with coronavirus disease 2019 (COVID-19) may develop pulmonary bacterial coinfection or superinfection, that could unfavorably impact their prognosis. RECENT FINDINGS: The exact burden of methicillin-resistant Staphylococcus aureus (MRSA) lung infection in peculiar populations such as patients with COVID-19 remains somewhat elusive, possibly because of wide heterogeneity in methods and endpoints across studies. SUMMARY: There was important heterogeneity in the retrieved literature on the epidemiology of MRSA lung infection in patients with COVID-19, both when considering all other bacteria as the denominator (relative prevalence ranging from 2% to 29%) and when considering only S. aureus as the denominator (relative prevalence ranging from 11% to 65%). Overall, MRSA is among the most frequent causative agents of pulmonary infection in patients with COVID-19. Improving our ability to rapidly reach etiological diagnosis of bacterial lung infection in COVID-19 patients remains fundamental if we are to improve the rates of appropriate antibiotic therapy in patients with COVID-19 and concomitant/superimposed MRSA infection, at the same time avoiding antibiotic overuse in line with antimicrobial stewardship principles.