The year 2023 saw the publication of several studies in various areas of infectious diseases. The administration of corticosteroids decreased mortality in severe community-acquired pneumonia. Administration of doxycycline post-exposure prophylaxis reduced the risk of bacterial sexually transmitted infections at the risk of resistance selection. An herbal preparation decreased mortality in sepsis. A meta-analysis concludes that oseltamivir does not significantly reduce the risk of hospitalisation for influenza. Discontinuation of antibiotic prophylaxis during dental procedures in Sweden did not increase the incidence of viridans group Streptococcus endocarditis. Several studies have led to the introduction of RSV (Respiratory Syncytial Virus (RSV) vaccination. 2023 also saw the resurgence of invasive Group A Streptococcal infections, of which clinicians must be wary.