A case-case study on the effect of primary and booster immunization with China-produced COVID-19 vaccines on prevention of pneumonia and viral load among vaccinated persons infected by Delta and Omicron variants

doi:10.1080/22221751.2022.2103455

. 2022 Dec;11(1):1950-1958.

doi: 10.1080/22221751.2022.2103455.

A case-case study on the effect of primary and booster immunization with China-produced COVID-19 vaccines on prevention of pneumonia and viral load among vaccinated persons infected by Delta and Omicron variants

Dan Wu¹, Ying Ye², Lin Tang¹, Ai-Bin Wang³, Rui Zhang⁴, Zhao-Hui Qian⁵, Fu-Zhen Wang¹, Hui Zheng¹, Chang Huang^{6

7}, Xiao-Ya Lv⁸, Hai-Feng Wang², Yan-Yang Zhang², Jing-Jing Pan², Ya-Fei Li², Ming-Xia Lu², Chang-Shuang Wang², Ya-Ting Ma², Zhi-Jie An¹, Lance Everett Rodewald¹, Zun-Dong Yin¹, Xuan-Yi Wang^{9

10}, Zhi-Yin Wu⁸, Yi-Ming Shao¹¹

Affiliations

¹ National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
² Henan Provincial Disease Control and Prevention, People's Republic of China, Henan.
³ Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.
⁴ National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
⁵ NHC Key laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
⁶ Chinese Field Epidemiology Training Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
⁷ Nanning Center for Disease Control and Prevention, Guangxi, People's Republic of China.
⁸ Development Center for Medicine and Science &Technology, National Health Commission, People's Republic of China, Beijing.
⁹ Key Laboratory of Medical Molecular Virology of MoE & MoH, Shanghai Institute of Infectious Disease and Biosecurity, Shanghai, People's Republic of China.
¹⁰ Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
¹¹ State Key Laboratory of Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.

PMID: 35850623
PMCID: PMC9359169
DOI: 10.1080/22221751.2022.2103455

A case-case study on the effect of primary and booster immunization with China-produced COVID-19 vaccines on prevention of pneumonia and viral load among vaccinated persons infected by Delta and Omicron variants

Dan Wu et al. Emerg Microbes Infect. 2022 Dec.

. 2022 Dec;11(1):1950-1958.

doi: 10.1080/22221751.2022.2103455.

Authors

Affiliations

¹ National Immunization Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
² Henan Provincial Disease Control and Prevention, People's Republic of China, Henan.
³ Beijing Ditan Hospital, Capital Medical University, Beijing, People's Republic of China.
⁴ National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
⁵ NHC Key laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
⁶ Chinese Field Epidemiology Training Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
⁷ Nanning Center for Disease Control and Prevention, Guangxi, People's Republic of China.
⁸ Development Center for Medicine and Science &Technology, National Health Commission, People's Republic of China, Beijing.
⁹ Key Laboratory of Medical Molecular Virology of MoE & MoH, Shanghai Institute of Infectious Disease and Biosecurity, Shanghai, People's Republic of China.
¹⁰ Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
¹¹ State Key Laboratory of Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.

PMID: 35850623
PMCID: PMC9359169
DOI: 10.1080/22221751.2022.2103455

Abstract

Using a three-prefecture, two-variant COVID-19 outbreak in Henan province in January 2022, we evaluated the associations of primary and booster immunization with China-produced COVID-19 vaccines and COVID-19 pneumonia and SARS-CoV-2 viral load among persons infected by Delta or Omicron variant. We obtained demographic, clinical, vaccination, and multiple Ct values of infections ≥3 years of age. Vaccination status was either primary series ≥180 days prior to infection; primary series <180 days prior to infection, or booster dose recipient. We used logistic regression to determine odds ratios (OR) of Delta and Omicron COVID-19 pneumonia by vaccination status. We analysed minimum Ct values by vaccination status, age, and variant. Of 826 eligible cases, 405 were Delta and 421 were Omicron cases; 48.9% of Delta and 19.0% of Omicron cases had COVID-19 pneumonia. Compared with full primary vaccination ≥180 days before infection, the aOR of pneumonia was 0.48 among those completing primary vaccination <180 days and 0.18 among booster recipients among these Delta infections. Among Omicron infections, the corresponding aOR was 0.34 among those completing primary vaccination <180 days. There were too few (ten) Omicron cases among booster dose recipients to calculate a reliable OR. There were no differences in minimum Ct values by vaccination status among the 356 Delta cases or 70 Omicron cases. COVID-19 pneumonia was less common among Omicron cases than Delta cases. Full primary vaccination reduced pneumonia effectively for 6 months; boosting six months after primary vaccination resulted in further reduction. We recommend accelerating the pace of booster dose administration.

Keywords: COVID-19 vaccine; Ct value; booster immunization; case-case study; real-world study.

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Figures

**Figure 1.**
Case-case study flow chart and study subjects.

**Figure 2.**
Minimum Ct value study subjects.

See this image and copyright information in PMC

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References

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[1] World Health Organization . Available from: https://covid19.who.int/.

[2] World Health Organization . Available from: https://covid19.who.int/.

[3] Wu D, Zhang Y, Tang L, et al. . Effectiveness of inactivated COVID-19 vaccines against symptomatic, pneumonia, and severe disease caused by the Delta variant: real world study and evidence - China, 2021. China CDC Wkly. 2022;4(4):57–65. - PMC - PubMed

[4] Wu D, Zhang Y, Tang L, et al. . Effectiveness of inactivated COVID-19 vaccines against symptomatic, pneumonia, and severe disease caused by the Delta variant: real world study and evidence - China, 2021. China CDC Wkly. 2022;4(4):57–65. - PMC - PubMed

[5] Jara A, Undurraga EA, Gonzalez C, et al. . Effectiveness of an inactivated SARS-CoV-2 vaccine in Chile. N Engl J Med. 2021;385(10):875–884. - PMC - PubMed

[6] Jara A, Undurraga EA, Gonzalez C, et al. . Effectiveness of an inactivated SARS-CoV-2 vaccine in Chile. N Engl J Med. 2021;385(10):875–884. - PMC - PubMed

[7] Kang M, Yan Li YY, Sun L, et al. . Effectiveness of inactivated COVID-19 vaccines against COVID-19 pneumonia and severe illness caused by the B.1.617.2 (Delta) variant: evidence from an outbreak in Guangdong, China: A Cohort Study. Ann Intern Med. 2021;175(4):533–540. - PMC - PubMed

[8] Kang M, Yan Li YY, Sun L, et al. . Effectiveness of inactivated COVID-19 vaccines against COVID-19 pneumonia and severe illness caused by the B.1.617.2 (Delta) variant: evidence from an outbreak in Guangdong, China: A Cohort Study. Ann Intern Med. 2021;175(4):533–540. - PMC - PubMed

[9] Embi PJ, Levy ME, Naleway AL, et al. . Effectiveness of 2-dose vaccination with mRNA COVID-19 vaccines against COVID-19-associated hospitalizations among immunocompromised adults - nine states, January-September 2021. MMWR Morb Mortal Wkly Rep. 2021;70(44):1553–1559. - PMC - PubMed

[10] Embi PJ, Levy ME, Naleway AL, et al. . Effectiveness of 2-dose vaccination with mRNA COVID-19 vaccines against COVID-19-associated hospitalizations among immunocompromised adults - nine states, January-September 2021. MMWR Morb Mortal Wkly Rep. 2021;70(44):1553–1559. - PMC - PubMed

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A case-case study on the effect of primary and booster immunization with China-produced COVID-19 vaccines on prevention of pneumonia and viral load among vaccinated persons infected by Delta and Omicron variants

Affiliations

A case-case study on the effect of primary and booster immunization with China-produced COVID-19 vaccines on prevention of pneumonia and viral load among vaccinated persons infected by Delta and Omicron variants

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