Discussion
This present study showed that COVID-19 patients with a history of
traveling in Wuhan had some clinical characteristics and laboratory
parameters that were different from COVID-19 patients who did not travel
in Wuhan. Lymphocytopenia, including the reduced CD3+,
CD4+ and CD8+ T cell counts on
hospital midterm were observed in Wuhan patients and percentage of
severe to critical cases in WH patients was significantly higher than
that in NWH patients, implying decrease in lymphocyte was related to the
severity of the disease, which is in agreement with the statement by
Zhang et al 8. The observation that patients
with COVID-19 with a history of traveling in Wuhan more prone to severe
diseases could be explained from two aspects, firstly, SARS-CoV-2 might
evolve adaptations to optimize its fitness to novel hosts during
human-to-human transmission, and viral adaptation may increase its
transmissibility but attenuate its pathogenesis, similar pattern have
also been observed in Ebola virus9. Since mutations
are part of the convergent evolution, it would be interesting to
investigate the dynamic intra-host genomic variations of SARS-CoV-2
during the transmission process of COVID-19 patients. Secondly, after
the outbreak in Wuhan, the local CDC strengthened the screen of COVID-19
patients, especially those with a traveling history to Wuhan and close
contacts with confirmed cases, early identification and treatment is an
efficient tactics to avoid the development of severe diseases.
Acknowledgments
The authors thank all the staff working in the Department of Infectious
Diseases from Shenzhen Third People’s Hospital for providing COVID-19
clinical data.
Funding This work was supported by the National Science and Technology Major
Project for Control and Prevention of Major Infectious Diseases of China
(No. 2017ZX10103004), the Guangdong Scientific and Technological Project
(NO. 2020B1111340076), and the Shenzhen Bay Laboratory Open Project (No.
SZBL202002271003).