After the full course of hepatitis B vaccination, about 5-10% of the vaccinees do not produce hepatitis B antibodies or produce only low titers of antibodies. Those who do not produce antibodies should increase the dose and number of doses of the vaccine, and children should receive multiple doses of hepatitis B vaccine until antibodies are produced. For those who do not respond to three doses of the immunization program, three more doses can be administered, and serum surface antibodies to hepatitis B can be tested 1-2 months after the second three doses of hepatitis B vaccine; if there is still no response, adults can receive one 60-μg dose of recombinant yeast hepatitis B vaccine.