In 2022, the coronavirus disease 2019 (COVID-19) continues to spread worldwide with the emergence of many variants. Healthcare workers (HCWs) are encouraged to be vaccinated against COVID-19 because vaccines provide powerful protection from serious illnesses, hospitalization, and death. However, breakthrough infections on vaccinees have been frequently reported, and more studies are required to understand the mechanism of breakthrough infection and establish a standard neutralizing antibody (NTAb) level with efficacy. In particular, it is important to develop useful research tools for HCWs at high risk of breakthrough infection. Here, we administered a brief questionnaire on awareness of COVID-19 vaccines and antibody tests to uncover the needs of HCWs. Our questionnaire showed that HCWs felt a lower priority for vaccines among infection control measures than non-HCWs. On the other hand, HCWs expected more strongly the vaccine to be effective in preventing infection at work than non-HCWs. About half of the respondents, whether HCWs or not, thought that there was a correlation between the severity of adverse reactions and the degree of antibody induction. About 20% of the respondents had a change in awareness of the correlation after an antibody survey. Many respondents believed that the antibody test would be useful. Therefore, we should contribute to the development of a method of evaluating vaccines that can protect against infection and to improving other infection control measures in the future.

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