1. Department of Epidemiology and Biostatistics, School of Public Health, Xi'an Jiaotong University Health Science Center
2. National Regional Children's Medical Center (Northwest), Key Laboratory of Precision Medicine to Pediatric Diseases of Shaanxi Province, Xi'an Key Laboratory of Children's Health and Diseases, Shaanxi
3. Department of Clinical Laboratory, Xi'an Children's Hospital
4. Xi’an Center for Disease Control and Prevention
5. Department of Diphtheria, Tetanus and Pertussis Vaccine and Toxins, National Institute for Food and Drug Control