Int J Biol Sci 2022; 18(12):4642-4647. doi:10.7150/ijbs.72424 This issue


Recipients of COVID-19 vaccines face challenges of SARS-CoV-2 variants

Tianhong Li1, Kathy Qian Luo1,2✉

1. Faculty of Health Sciences, University of Macau, Macao SAR, China
2. Ministry of Education-Frontiers Science Center for Precision Oncology, University of Macau, Taipa, Macao SAR, China

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Li T, Luo KQ. Recipients of COVID-19 vaccines face challenges of SARS-CoV-2 variants. Int J Biol Sci 2022; 18(12):4642-4647. doi:10.7150/ijbs.72424. Available from

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Graphic abstract

The coronavirus disease 19 (COVID-19) has been rampant since 2019, severely affecting global public health, and causing 5.75 million deaths worldwide. So far, many vaccines have been developed to prevent the infection of SARS-CoV-2 virus. However, the emergence of new variants may threat vaccine recipients as they might evade immunological surveillance that depends on the using of anti-SARS-CoV-2 antibody to neutralize the viral particles. Recent studies have found that recipients who received two doses of vaccination plus an additional booster shoot were able to quickly elevate neutralization response and immune response against wild-type SARS-CoV-2 virus and some initially appeared viral variants. In this review, we assessed the real-world effectiveness of different COVID-19 vaccines by population studies and neutralization assays and compared neutralization responses of booster vaccines in vitro. Finally, as the efficacy of COVID-19 vaccine is expected to decline over time, continued vaccination should be considered to achieve a long-term immune protection against coronavirus.

Keywords: COVID-19, SARS-CoV-2 virus, Vaccines, Viral variants, booster vaccination