Some questions about hepatitis B Q: If the HBsAg positive mother is e antigen positive and has a high HBV DNA titer level, some recommend that the patient check the HBV DNA in the breast milk and not breastfeed if it is positive. Is there any basis for this advice? A: According to a trial in Taiwan, if a newborn baby is given HBIG and hepatitis B vaccine within 12 hours of birth, the body has already produced surface antibodies to hepatitis B. Even if HBV is present in the mother’s milk, the surface antibodies can be neutralized when it enters the baby’s body and will not cause infection, so breastfeeding is still allowed. Currently the CDC and WHO recommend that HBsAg positive mothers can still breastfeed as long as they are passively and actively immunized. Q: Is there any evidence to support the use of monthly injections of HBIG in pregnant women during the last months of pregnancy, and is this method of immune blockade worth promoting or is there a better way? A: There are no definitive reports on the use of immunoglobulin injections in pregnant women to prevent mother-to-child transmission, and there is no higher level of evidence-based medical evidence. However, there is a good method to interrupt mother-to-child transmission. Immunoglobulin and hepatitis B vaccine combined with immunization immediately after the birth of a newborn can achieve a 95% to 97% interruption. There is no recommendation in the current WHO and Ministry of Health recommendations. The theoretical rationale for giving high-value immunoglobulin to pregnant women is to reduce HBV DNA in pregnant women, which is difficult to achieve in practice. One study found that after three injections of 200 IU immunoglobulin in pregnant women, no immunoglobulin could be detected in the serum of pregnant women and newborns. In addition, no changes in HBV DNA levels were found in 17 pregnant women examined before and after immunoglobulin injections. So from this evidence, the use of immunoglobulin to interrupt mother-to-child transmission is not well founded. Q: How should I consider the dose of vaccine to be administered when receiving hepatitis B vaccine? A: Generally speaking, the higher the dose, the better the effect. As of now, adults have a higher non-response (rate) after 10 μg of vaccine. The current recommended dose is consistent with the internationally accepted dose of 5 μg recombinant yeast vaccine for newborns of HBsAg-negative mothers, 10 μg recombinant yeast vaccine for newborns of HBsAg-positive mothers, 2O μg recombinant yeast vaccine for adults, and 4O μg recombinant yeast vaccine for immunodeficient individuals. Q: For mothers who are positive for e antigen and also positive for HBV DNA, what should I pay attention to during delivery? How much does natural delivery and cesarean section affect neonatal infection? A: Amniocentesis should be avoided, and the delivery time should be shortened to ensure the integrity of the placenta and minimize the exposure of the newborn to maternal blood. Therefore, cesarean section is not advocated if natural delivery is available, and it is better to deliver naturally, which can reduce the chance of the infant being exposed to the mother’s blood with the virus. Q: What should adults who are surface antigen negative do after 3 to 5 doses of 5μg to 10μg of hepatitis B vaccine are ineffective? A: Adults are recommended to use 2Oμg of recombinant yeast vaccine for three doses. If antibodies are still not produced (provided the reagents are reliable), there are two solutions: first, administer another 2Oμg dose of recombinant yeast hepatitis B vaccine; second, do not administer any more vaccines, as these people are low or no responders. Q: If you have received hepatitis B vaccine before and your antibodies have disappeared, can you get a booster dose instead of the full vaccination? If I get a booster dose, will I also have 95% positive antibodies and be protected for more than 15 years? A: To induce a high titer of immunity after the antibody has disappeared, it is recommended that one dose of hepatitis B vaccine be administered first and that the antibody level be tested after the vaccination. If antibodies are still absent after 1 dose of booster then 3 doses of vaccination are complete. Positive antibodies after 1 or 3 doses of 20 μg recombinant yeast hepatitis B vaccine will provide protection for more than 15 years. If you do not belong to a high-risk group such as medical personnel, and if you have produced antibodies from previous vaccinations and they have now disappeared, you may not receive a booster vaccination, as the immune memory that exists in your body can rapidly induce antibody production after re-exposure to the pathogen. Q: What is the specific method of vaccination for accidental emergency exposure? A: If the serum anti-HBs level of the exposed person is < 10 mIU or unknown, it is recommended to immediately administer HBIG 200-400 IU, while the hepatitis B vaccine can be administered in the other arm. Three doses of 0, 1, and 6 can be administered. A rapid vaccination program for accidental emergency exposures can also be initiated according to the vaccine's instructions: a day 0, 7, and 21 vaccination program is adopted and requires a fourth 2O g dose of recombinant yeast vaccine in the 12th month after the first dose. Q: How do you define a high-risk group for hepatitis B? Are family members of HBsAg-positive individuals in a high-risk group? Should college students living with HBsAg-positive individuals in college dormitories for a long time be defined as a high-risk group? A: High-risk groups are medical personnel, people who have frequent contact with blood, staff of childcare institutions, organ transplant patients, frequent recipients of blood transfusions or blood products, immunocompromised people, people prone to trauma, family members of HBsAg-positive people, men who are gay or have multiple sexual partners and people who inject drugs intravenously, etc. Family members of HBsAg-positive people belong to high-risk groups. People who have close contact with HBV-infected people are all high-risk groups. If there are HBV carriers in the college dormitory, others are in the high-risk group.