いわゆる第5波以降のCOVID-19感染症における胸部CT所見の検討

Chest CT findings in COVID-19 infections on or after the 5th wave of COVID-19 infection

2019年12月，中華人民共和国の湖北省武漢市で肺炎患者の集団発生が報告され，新型コロナウイルス感染症（coronavirus disease-2019：COVID-19）と命名された^1）。以来COVID-19は我が国を含む世界中に伝播し，放射線科医としてCOVID-19肺炎は接する機会が多い疾患となっている。COVID-19肺炎の胸部CT所見として，末梢優位の両側性すりガラス影や多発する円形のすりガラス影，reversed halo signなどが典型的であると報告されている^2）。

This study investigated the differences in the presence or absence and pattern of pneumonia between Delta and Omicron strains in the fifth and later waves of cases, as well as the relationship between vaccination and presence or absence and pattern of pneumonia in the Omicron strain. Significantly fewer patients with the Omicron strain presented with pneumonia than with the Delta strain, and more cases showed atypical imaging findings. In patients with the Omicron strain, patients without a history of vaccination may be more likely to present typical imaging findings.