Vaccinations are still the most economical, direct and effective means of disease prevention, and parents should take a scientific view of vaccines and bring their children for immunization on time. However, it is worth noting that vaccination is not “once and for all”. The effectiveness of vaccines varies with the quality of the vaccine itself and with the recipient’s own constitution, and like drugs, it is not guaranteed to be safe and effective for every recipient. Can I find out if a vaccine is effective? There are two ways to check if a vaccine is safe and effective. 1. Check your own antibody level Currently, most hospitals can only test antibody levels for hepatitis B. For other types of vaccines, most medical institutions do not provide antibody verification. Certain testing facilities can test for antibodies to multiple vaccines. 2. Check the vaccine itself We can also determine this by checking the vaccine itself. Check vaccination records and compare vaccine manufacturers and lot numbers. Of course, you can also consult the vaccination unit. If some of the vaccines in the vaccination book only show the batch number but not the manufacturer, you can check the website of the China Academy of Food and Drug Administration.