Medical Knowledge Refresher

ulcer vs Duodenal Ulcer Comparison

🔬Infectious Diseases Update – May 2026

for COVID-19 Prevention After Household Exposure**

A major clinical trial involving more than 2,000 participants found that a 5-day course of **ensitrelvir**, started within **72 hours of household exposure** to COVID-19, reduced the risk of developing infection by approximately **67%** compared with placebo (2.9% vs 9%).

✅ Well tolerated, with only a temporary reduction in HDL ("good") cholesterol reported.

Current recommendations suggest considering ensitrelvir for individuals at **high risk of severe COVID-19**, including:
• Adults aged ≥65 years
• Patients with significant medical comorbidities
• Immunocompromised individuals

📌 Treatment should be initiated **as soon as possible and within 72 hours of exposure** to a confirmed COVID-19 case.

Ensitrelvir is currently available in Japan and has recently received approval from the U.S. FDA.