Superspreading potentials of SARS-CoV-2 Delta variants across different contact settings in Eastern China: A retrospective observational study. Issue 5 (May 2023)

• Record Type: Journal Article
• Authors: Wang, Kai; Luan, Zemin; Guo, Zihao; Lei, Hao; Zeng, Ting; Yu, Lin; Li, Hujiaojiao; Tian, Maozai; Ran, Jinjun; Zhao, Shi
• Is Part Of: Journal of infection and public health. Volume 16:Issue 5(2023)
• Page Start: 689
• Page End: 696
• Publication Date: 2023-05
• Subjects: COVID-19 -- Delta variant -- Superspreading -- Contact tracing -- China; Communicable diseases -- Periodicals; Public health -- Periodicals; Epidemiology -- Periodicals; Nosocomial infections -- Prevention -- Periodicals; Medical microbiology -- Periodicals; 614.4
• DOI: 10.1016/j.jiph.2023.02.024
• Languages: English
• ISSNs: 1876-0341

Abstract

Abstract: Objectives: As the genetic variants of SARS-CoV-2 continuously pose threats to global health, evaluating superspreading potentials of emerging genetic variants is of importance for region-wide control of COVID-19 outbreaks. Methods: By using detailed epidemiological contact tracing data of test-positive COVID-19 cases collected between July and August 2021 in Nanjing and Yangzhou, China, we assessed the superspreading potential of outbreaks seeded by SARS-CoV-2 Delta variants. The transmission chains and case-clusters were constructed according to the individual-based surveillance data. We modelled the disease transmission as a classic branching process with transmission heterogeneity governed by negative binomial models. Subgroup analysis was conducted by different contact settings and age groups. Results: We reported a considerable heterogeneity in the contact patterns and transmissibility of Delta variants in eastern China. We estimated an expected 14% (95% CI: 11–16%) of the most infectious cases generated 80% of the total transmission. Conclusions: Delta variants demonstrated a significant potential of superspreading under strict control measures and active COVID-19 detecting efforts. Enhancing the surveillance on disease transmissibility especially in high-risk settings, along with rapid contact tracing and case isolations would be one of the key factors to mitigate the epidemic caused by the emerging genetic variants of SARS-CoV-2.