The goal of this observational study is to learn about antibody level of tetanus of adults in high-income city of china. The main question it aims to answer is:
1. Analysis of tetanus antibody distribution across different age groups
2. Evaluation of the TQS method for determining antibody status
3. Correlation between primary vaccination history and tetanus antibody concentrations Blood samples were voluntarily provided by adult healthy participants for tetanus antibody analysis over a continuous collection period of more than one year.