Clinical and Pulmonary CT Characteristics of Patients Infected With the SARS-CoV-2 Omicron Variant Compared With Those of Patients Infected With the Alpha Viral Strain

Naibin Yang; Chuwen Wang; Jiajia Huang; Jing Dong; Jihui Ye; Yuan Fu; Jingfeng Huang; Daojie Xu; Gang Cao; Guoqing Qian

doi:10.3389/fpubh.2022.931480

Clinical and Pulmonary CT Characteristics of Patients Infected With the SARS-CoV-2 Omicron Variant Compared With Those of Patients Infected With the Alpha Viral Strain

Front Public Health. 2022 Jul 12:10:931480. doi: 10.3389/fpubh.2022.931480. eCollection 2022.

Authors

Naibin Yang¹, Chuwen Wang², Jiajia Huang², Jing Dong³, Jihui Ye⁴, Yuan Fu⁵, Jingfeng Huang⁵, Daojie Xu⁶, Gang Cao⁷, Guoqing Qian¹

Affiliations

¹ Department of Infectious Diseases, Ningbo First Hospital, Ningbo University, Ningbo, China.
² School of Medicine, Ningbo University, Ningbo, China.
³ Department of Emergency, Ningbo First Hospital, Ningbo University, Ningbo, China.
⁴ Department of Intensive Care Unit, Ningbo First Hospital, Ningbo University, Ningbo, China.
⁵ Department of Radiology, Ningbo First Hospital, Ningbo University, Ningbo, China.
⁶ Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai, China.
⁷ Department of Anesthesiology and Pain Medical Center, Ningbo First Hospital, Ningbo University, Ningbo, China.

Abstract

Background: Omicron has become the dominant variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) globally. We aimed to compare the clinical and pulmonary computed tomography (CT) characteristics of the patients infected with SARS-CoV-2 Omicron with those of patients infected with the Alpha viral strain.

Methods: Clinical profiles and pulmonary CT images of 420 patients diagnosed with coronavirus disease-2019 (COVID-19) at Ningbo First Hospital between January 2020 and April 2022 were collected. Demographic characteristics, symptoms, and imaging manifestations of patients infected with the SARS-CoV-2 Omicron variant were compared with those of patients infected with the Alpha strain.

Results: A total of 38 patients were diagnosed to be infected with the Alpha strain of SARS-CoV-2, whereas 382 patients were thought to be infected with the Omicron variant. Compared with patients infected with the Alpha strain, those infected with the Omicron variant were younger, and a higher proportion of men were infected (P < 0.001). Notably, 93 (24.3%) of the patients infected with Omicron were asymptomatic, whereas only two (5.3%) of the patients infected with the Alpha strain were asymptomatic. Fever (65.8%), cough (63.2%), shortness of breath (21.1%), and diarrhea (21.1%) were more common in patients infected with the SARS-CoV-2 Alpha strain, while runny nose (24.1%), sore throat (31.9%), body aches (13.6%), and headache (12.3%) were more common in patients with the Omicron variant. Compared with 33 (86.84%) of 38 patients infected with the Alpha strain, who had viral pneumonia on pulmonary CT images, only 5 (1.3%) of 382 patients infected with the Omicron variant had mild foci. In addition, the distribution of opacities in the five patients was unilateral and centrilobular, whereas most patients infected with the Alpha strain had bilateral involvement and multiple lesions in the peripheral zones of the lung.

Conclusion: The SARS-CoV-2 Alpha strain mainly affects the lungs, while Omicron is confined to the upper respiratory tract in patients with COVID-19.

Keywords: Alpha; COVID-19; Omicron; SARS-CoV-2; computed tomography.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

COVID-19* / diagnostic imaging
Humans
Lung / diagnostic imaging
Lung / pathology
Male
SARS-CoV-2*
Tomography, X-Ray Computed

Supplementary concepts

SARS-CoV-2 variants