
==== Front
Hum Vaccin Immunother
Hum Vaccin Immunother
Human Vaccines & Immunotherapeutics
2164-5515
2164-554X
Taylor & Francis

10.1080/21645515.2024.2380568
2380568
Version of Record
Letter to the Editor
Coronavirus
Response to comment on ‘Clinical characteristics and risk factors for ZF2001 fully vaccinated inpatients with COVID-19: A retrospective cohort study’
L. JIN ET AL.
HUMAN VACCINES & IMMUNOTHERAPEUTICS
Jin Liping a b c d e *
Le Jiayuan a b c d e *
Sun Yuming b c d e f
Zeng Furong e g
a Department of Dermatology, Xiangya Hospital, Central South University , Changsha, Hunan, China
b National Engineering Research Center of Personalized Diagnostic and Therapeutic Technology , China
c Furong Laboratory , Changsha, Hunan, China
d Hunan Key Laboratory of Skin Cancer and Psoriasis, Hunan Engineering Research Center of Skin Health and Disease, Xiangya Hospital, Central South University , Changsha, Hunan, China
e National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University , Changsha, Hunan, China
f Department of Plastic and Cosmetic Surgery, Xiangya Hospital, Central South University , Changsha, Hunan, China
g Department of Oncology, Xiangya Hospital, Central South University , Changsha, Hunan, China
CONTACT Furong Zeng zengfurong@csu.edu.cn Department of Oncology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan, China.
Yuming Sun 962881298@qq.com Department of Plastic and Cosmetic Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.
* Equal contribution.

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© 2024 The Author(s). Published with license by Taylor & Francis Group, LLC.
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The Author(s)
https://creativecommons.org/licenses/by-nc/4.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. The terms on which this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent.

The author(s) reported there is no funding associated with the work featured in this article.
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pmcTo the Editor,

We appreciate the interest in our article entitled “Clinical Characteristics and Risk Factors for ZF2001 Fully Vaccinated Inpatients with COVID-19: A Retrospective Cohort Study.”

Firstly, Gao et al. mentioned that 10 outcomes analyzed per variable are required for the prediction analysis model according to basic statistical analysis rules.1 In our analysis, we initially conducted a univariate COX regression to identify statistically significant hematological indicators. Subsequently, we performed a multivariate COX regression analysis, adjusting for sex, age, comorbidities, antiviral therapy, and steroid therapy. In our model, only age and a single hematological marker were considered predictor parameters, with 26 eligible composite outcome COVID-19 patients, similar to those in previous studies.2,3 Fisher’s exact test is also appropriate to compare the significant variables between patients with and without composite outcomes. However, we also focused on the clinical characteristics of ZF2001 fully vaccinated inpatients with COVID-19 and therefore listed the baseline characteristics of patients in Table 1 of original paper.4Table 1. Reference intervals of laboratory parameters.

Laboratory parameters	Reference intervals	
White blood cell (109/L)	3.5–9.5	
Blood platelet (109/L)	125–350	
Lymphocyte (109/L)	1.1–3.2	
Albumin (g/L)	40–55	
Serum creatinine (μmol/L)	41–111	
Blood urea nitrogen (mmol/L)	3.6–9.5	
Lactate dehydrogenase (U/L)	109245	
Troponin (U/L)	0–0.02	
D-Dimer (mg/L)	0–0.5	
Procalcitonin (ng/ml)	0–0.1	

Secondly, Gao et al. questioned how we selected the cutoff values for each laboratory parameter. We relied on the reference intervals provided by the clinical laboratory at Xiangya Hospital, Central South University to determine these cutoff values (Table 1). These reference intervals are based on the “Reference Intervals of Blood Cell Analysis”5 and “Reference Intervals for Common Clinical Biochemistry Tests,”6 issued by the National Health Commission of the People’s Republic of China. For instance, the normal reference range for platelets is 125–350 × 10^9/L; therefore, we defined platelet counts < 125 × 10^9/L as thrombocytopenia.

Thirdly, Gao et al. raised concerns about the timing of the documented laboratory parameters in our study. These parameters were obtained from data collected after the patient’s initial test upon hospital admission. As a retrospective observational study, there are inherent limitations in data acquisition, with all confounding factors not being entirely excluded, such as drug use. To further clarify the risk factors for disease progression in fully vaccinated COVID-19 inpatients, more prospective studies are necessary to substantiate our findings.

Sincerely,

Furong Zeng,

Xiangya hospital, Central South University, 87 Xiangya Road, Changsha 410,008, China. E-mail:

zengflorachn@hotmail.com;

Acknowledgments

We sincerely thank for the encouragement of all members in the Xiangya Hospital, Central South University.

Disclosure statement

No potential conflict of interest was reported by the author(s).
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