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. 2022 Apr 28;74(8):1485-1488.
doi: 10.1093/cid/ciab684.

False Coronavirus Disease 2019 Cases due to Contamination by Inactivated Virus Vaccine

Kelvin Kai-Wang To  1   2 , Xin Li  1   2 , David Christopher Lung  3 , Jonathan Daniel Ip  1 , Wan-Mui Chan  1 , Allen Wing-Ho Chu  1 , Cyril Chik-Yan Yip  2 , Jonathan H K Chen  2 , Rosana Wing-Shan Poon  2 , Hoi-Wah Tsoi  1 , Raymond Wai-Man Lai  4 , Wing-Kin To  5 , Lili Ren  6   7 , Mingkun Li  8   9 , Yunlong Cao  10 , Xiaoliang Sunney Xie  10   11 , Dong-Yan Jin  12 , Kwok-Yung Yuen  1   2
Affiliations

False Coronavirus Disease 2019 Cases due to Contamination by Inactivated Virus Vaccine

Kelvin Kai-Wang To et al. Clin Infect Dis. .

Abstract

A false-positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse-transcription polymerase chain reaction result can lead to unnecessary public health measures. We report 2 individuals whose respiratory specimens were contaminated by an inactivated SARS-CoV-2 vaccine strain (CoronaVac), likely at vaccination premises. Incidentally, whole genome sequencing of CoronaVac showed adaptive deletions on the spike protein, which do not result in observable changes of antigenicity.

Keywords: contamination; false positive; inactivated COVID-19 vaccine.

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Figures

Figure 1.
Figure 1.
Whole viral genome analysis of case 1. A, Schematic diagram showing the mutations of case 1, CoronaVac vaccine strain (sequenced in this study), and published sequences of CoronaVac (SARS-CoV-2/human/CHN/CN2/2020 and SARS-CoV-2/human/CHN/CN1/2020). Wuhan-Hu-1 (GenBank accession number MN908947.3) was used as the reference genome. B, Whole genome phylogenetic analysis showing the relationship between case 1, CoronaVac vaccine sequences, and genomes from different Pango lineages. The trees were constructed by maximum likelihood method. The reference genome Wuhan-Hu-1 (GenBank accession number MN908947.3) is used as the root of the tree. Abbreviations: HK, Hong Kong; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.
See this image and copyright information in PMC

References

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