Clinical characteristics and immune profile alterations in vaccinated individuals with breakthrough Delta SARS-CoV-2 infections

• Published in: Nature communications Vol. 13; no. 1; p. 3979
• Main Authors: Fan, Qinghong, Shi, Jingrong, Yang, Yanhong, Tang, Guofang, Jiang, Mengling, Li, Jiaojiao, Tang, Jingyan, Li, Lu, Wen, Xueliang, Zhang, Lieguang, Deng, Xizi, Wang, Yaping, Lan, Yun, Li, Liya, Peng, Ping, Tong, Yuwei, Lu, Huan, Yan, Lili, Liu, Ying, Cai, Shuijiang, Li, Yueping, Mo, Xiaoneng, Li, Meiyu, Deng, Xilong, Hu, Zhongwei, Yu, Haisheng, Hu, Fengyu, Liu, Jinxin, Tang, Xiaoping, Li, Feng
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09-07-2022; Nature Publishing Group; Nature Portfolio
• Subjects: 13/1; 13/21; 13/31; 38/39; 38/79; 631/250/255/2514; 631/326/107; 631/326/596/4130; 692/699/255/2514; Cytokine storm; Cytokines; Humanities and Social Sciences; Immune clearance; Immunization; Infections; Leukocytes (mononuclear); multidisciplinary; Peripheral blood mononuclear cells; Pneumonia; Public health; Science; Science (multidisciplinary); Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Vaccines; Viral diseases
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-31693-7

Despite timely immunization programs, and efficacious vaccines conveying protection against SARS-CoV-2 infection, breakthrough infections in vaccinated individuals have been reported. The Delta variant of concern (VOC) outbreak in Guangzhou resulted in local transmission in vaccinated and non-vaccinated residents, providing a unique opportunity to study the protective effects of the inactivated vaccines in breakthrough infection. Here, we find that the 2-dose vaccinated group has similar peak viral titers and comparable speeds of viral RNA clearance to the non-vaccinated group but accelerated viral suppression in the middle course of the disease. We quantitatively demonstrate that peak viral pneumonia is significantly mitigated in the 2-dose vaccine group (median 0.298%) compared with the non-vaccinated (5.77%) and 1-dose vaccine (3.34%) groups. Pneumonia absorbance is approximately 6 days ahead in the 2-dose group (median 10 days) than in the non-vaccinated group (16 days) (
p
 = 0.003). We also observe reduced cytokine inflammation and markedly undisturbed gene transcription profiles of peripheral blood mononuclear cells (PBMCs) in the 2-dose group. In short, our study demonstrates that prior vaccination substantially restrains pneumonia development, reduces cytokine storms, and facilitates clinical recovery.
SARS-CoV-2 breakthrough infections in vaccinated individuals are a public health concern. Here, the authors analyse the clinical characteristics and profile immune alterations among vaccinated and non-vaccinated residents with Delta SARS-CoV-2 infection in Guangzhou.