Hepatitis B vaccine
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Sara Mehrsefat, M.D. [2]
Overview
Hepatitis B Vaccine
Hepatitis B vaccine is a vaccine developed for the prevention of hepatitis B virus infection. These rely on the use of one of the viral envelope proteins (hepatitis B surface antigen or HBsAg). The vaccine was originally prepared from plasma obtained from patients who had long-standing hepatitis B virus infection. However, currently, these are more often made using recombinant DNA technology, though plasma-derived vaccines continue to be used; the two types of vaccines are equally effective and safe.[citation needed]
Many countries now routinely vaccinate infants against hepatitis B. Babies born to HBeAg positive mothers are strongly recommended to be vaccinated and injected with immune globulin immediately after birth, so as to prevent transmission of infection. In many areas, vaccination against hepatitis B is also required for all health-care workers. Some college campus housing units now require proof of vaccination as a prerequisite. Booster doses are not needed for low-risk general population. Some recommend such doses every five to ten years for health-care workers, though the evidence supporting such doses is quite limited.
The vaccine is highly effective. In endemic countries with high rates of hepatitis B infection, vaccination of newborns has not only reduced the risk of infection, but has also led to marked reduction in liver cancer. This was reported in Taiwan where the implementation of a nationwide hepatitis B vaccination program in 1984 was associated with a decline in the incidence of childhood hepatocellular carcinoma.[1] In that sense, this vaccine can be thought of as an anti-cancer vaccine.
Patients with HIV appear to have inferior antibody responses to hepatitis B vaccination.[2] This is not surprising, because some HIV-positive people have damaged immune systems: this may happen even before opportunistic infections take hold, thus justifying a diagnosis of AIDS.
It is not known whether vaccination with hepatitus B vaccine would cause rejection of a donor's blood by a blood bank that routinely tests blood for hepatitus B antibodies, as most now do—and have been doing since the mid-1980's. This is worth discussing with a doctor.
Another question has arisen: What is the value of vaccinating an infant against a sexually-transmitted disease, using a vaccine that confers immunity for only seven years? This point has been raised by Judith Reisman, whose credibility on other matters is suspect, but this point seems cogent. Unless the parents expected the child to be molested at an unusually early age, the vaccination would probably be wasted. Of course, the child might have consensual sex at 15 or 17, and the immunity might last longer than the guarantee, in which case it might help. (Is there a guarantee? In most jurisdictions, the statute of limitations for civil suits is one to three years, so a seven-year guarantee would be inherently unenforceable.) Alternatively, the parents might arrange for booster vaccinations every seven years: at 21 years, the booster might be needed, because most 21-year-olds have sex at least occasionally.[citation needed]
The hepatitis B vaccine is the mainstay of hepatitis B prevention. WHO recommends that all infants receive the hepatitis B vaccine as soon as possible after birth, preferably within 24 hours. The birth dose should be followed by 2 or 3 doses to complete the primary series. In most cases, 1 of the following 2 options is considered appropriate:
a 3-dose schedule of hepatitis B vaccine, with the first dose (monovalent) being given at birth and the second and third (monovalent or combined vaccine) given at the same time as the first and third doses of diphtheria, pertussis (whooping cough), and tetanus – (DTP) vaccine; or a 4-dose schedule, where a monovalent birth dose is followed by three monovalent or combined vaccine doses, usually given with other routine infant vaccines. The complete vaccine series induces protective antibody levels in more than 95% of infants, children and young adults. Protection lasts at least 20 years and is probably lifelong. Thus, WHO does not recommend booster vaccination for persons who have completed the 3 dose vaccination schedule.
All children and adolescents younger than 18 years-old and not previously vaccinated should receive the vaccine if they live in countries where there is low or intermediate endemicity. In those settings it is possible that more people in high-risk groups may acquire the infection and they should also be vaccinated. They include:
people who frequently require blood or blood products, dialysis patients, recipients of solid organ transplantations; people interned in prisons; persons who inject drugs; household and sexual contacts of people with chronic HBV infection; people with multiple sexual partners; health-care workers and others who may be exposed to blood and blood products through their work; and travellers who have not completed their hepatitis B vaccination series, who should be offered the vaccine before leaving for endemic areas. The vaccine has an excellent record of safety and effectiveness. Since 1982, over 1 billion doses of hepatitis B vaccine have been used worldwide. In many countries where between 8–15% of children used to become chronically infected with the hepatitis B virus, vaccination has reduced the rate of chronic infection to less than 1% among immunized children.
As of 2014, 184 Member States vaccinate infants against hepatitis B as part of their vaccination schedules and 82% of children in these states received the hepatitis B vaccine. This is a major increase compared with 31 countries in 1992, the year that the World Health Assembly passed a resolution to recommend global vaccination against hepatitis B. Furthermore, as of 2014, 96 Member States have introduced the hepatitis B birth dose vaccine.
In addition, implementing of blood safety strategies, including quality-assured screening of all donated blood and blood components used for transfusion, can prevent transmission of HBV. Safe injection practices, eliminating unnecessary and unsafe injections, can be effective strategies to protect against HBV transmission. Furthermore, safer sex practices, including minimizing the number of partners and using barrier protective measures (condoms), also protect against transmission.
Recombinant DNA-derived vaccines against HBV have been available for more than two decades. The primary hepatitis B immunization series conventionally consists of three doses of vaccine. Vaccination of infants and, in particular, delivery of hepatitis B vaccine within 24 hours of birth is 90–95% effective in preventing infection with HBV as well as decreasing HBV transmission if followed by at least two other doses. WHO recommends universal hepatitis B vaccination for all infants, and that the first dose should be given as soon as possible after birth.[3]This strategy has resulted in a dramatic decrease in the prevalence of CHB among young children in regions of the world where universal infant vaccination programs have been implemented. A proportion of vaccinated children (5–10%) have a poor response to vaccination, and will remain susceptible as adults to acquisition of HBV infection.:[4][5]
Vaccination recommendation
Hepatitis B vaccination recommendation in Infant and neonates include:[4]
- All infants should receive their first dose of hepatitis B vaccine as soon as possible after birth, preferably within 24 hours, followed by two or three doses.
Hepatitis B vaccination recommendation in adults include:[6][7]
- Any person who wants to be protected from HBV infection
- Patient with diabetes mellitus (age 60 years or older with diabetes mellitus, at the discretion of the treating clinician)
- Patient with end-stage renal disease, including patients receiving hemodialysis; HIV infection; or chronic liver disease
- Sexually active and not in a long-term, mutually monogamous relationship (e.g., more than 1 sex partner during the previous 6 months)
- Seeking evaluation or receiving treatment for a sexually transmitted infection (STI)
- A male who has sex with males
- A current or recent injection-drug user
- At occupational risk of infection through exposure to blood or blood-contaminated body fluids
- Health care worker
- Public safety worker
- Trainee in a health professional or allied health school
- Residents or staff of an institution for persons with developmental disabilities
- Sex partner or household member of a person who is chronically infected with HBV (HBsAg-positive)
- People living in correctional facilities
- All teenagers ages 18 and younger who are not fully vaccinated
- Planned travel to a country with high or intermediate prevalence of endemic HBV infection
- Hepatitis B vaccination should be administered to all unvaccinated people traveling to areas with intermediate to high prevalence of chronic hepatitis B (HBV surface antigen prevalence ≥2%)
Recommended schedule
The vaccination schedule
- Children and adults 3 intramuscular injections, the second and third doses administered 1 and 6 months
Licensed hepatitis B vaccines in the United States
Currently licensed hepatitis B vaccines in the United States:[6]|
- Single-antigen hepatitis B vaccines
- ENGERIX-B
- RECOMBIVAX HB
- Combination vaccines
- PEDIARIX: Combined hepatitis B, diphtheria, tetanus, acellular pertussis (DTaP), and inactivated poliovirus (IPV) vaccine. Cannot be administered before age 6 weeks or after age 7 years.
- TWINRIX: Combined Hepatitis A and hepatitis B vaccine. Recommended for persons aged ≥18 years who are at increased risk for both Hepatitis A virus and HBV infections.
- COMVAX: (discontinued for purchase as of December 2014): Combined hepatitis B-Haemophilus influenzae type b (Hib) conjugate vaccine. Cannot be administered before age 6 weeks or after age 71 months.
Recommended doses of hepatitis B vaccines
Interrupted Vaccination
interruption between doses of hepatitis B vaccination:[6]
- After the first dose, the second dose should be administered as soon as possible
- The second and third doses should be separated by an interval of at least 8 weeks
- Only the third dose is delayed, it should be administered as soon as possible
Contraindications
Hepatitis B vaccine is contraindicated in a person who has experienced a serious systemic or anaphylactic reaction to a prior dose of the vaccine.
References
- ↑ Chang MH, Chen CJ, Lai MS, Hsu HM, Wu TC, Kong MS, Liang DC, Chau WY, Chen DS (1997). "Universal hepatitis B vaccination in Taiwan and the incidence of hepatocellular carcinoma in children. Taiwan Childhood Hepatoma Study Group". N Engl J Med. 336 (26): 1855–9. PMID 9197213.
- ↑ Pasricha N, Datta U, Chawla Y, Singh S, Arora S, Sud A, Minz R, Saikia B, Singh H, James I, Sehgal S (2006). "Immune responses in patients with HIV infection after vaccination with recombinant Hepatitis B virus vaccine". BMC Infect Dis. 6: 65. PMID 16571140.
- ↑ Ni JD, Xiong YZ, Wang XJ, Xiu LC. Does increased hepatitis B vaccination dose lead to a better immune response in HIV- infected patients than standard dose vaccination: a meta-analysis? Int J STD AIDS. 2013;24(2):117–22.
- ↑ 4.0 4.1 World Health Organization, Guidelines for the Prevention, Care, and Treatment of persons with chronic Hepatitis B Infection. (March 2015). http://apps.who.int/iris/bitstream/10665/154590/1/9789241549059_eng.pdf Accessed on October 4th, 2016
- ↑ Liu CJ, Liou JM, Chen DS, Chen P J.Natural course and treatment of dual hepatitis B virus and hepatitis C virus infections. J Formos Med Assoc Taiwan. 2005;104(11):783–91.
- ↑ 6.0 6.1 6.2 6.3 Centers for Disease Control and Prevention. Hepatitis B (2016) http://www.cdc.gov/hepatitis/hbv/hbvfaq.htm#vaccFAQ Accessed on September 29, 2016
- ↑ Centers for Disease Control and Prevention. Infectious Diseases Related to Travel. Hepatitis B. (2015) http://wwwnc.cdc.gov/travel/yellowbook/2016/infectious-diseases-related-to-travel/hepatitis-b#4621 Accessed on October 4th, 2016