A Hepatologist’s Perspective: Why a Unified National Program for Infant Immunization Against Hepatitis B Should Be Implemented

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Hepatitis B virus (HBV) is a highly contagious viral infection of the liver that can lead to cirrhosis and liver cancer. Transmission occurs vertically from mother to infant or horizontally, through exchange of bodily fluids including saliva or open wounds which can occur in preschools and at daycare. A safe and effective vaccine is available, and as of 2007, 171 of 193 WHO members had implemented a policy of universal HBV vaccination in infants. In contrast, based on ecologic data suggesting a higher risk in adolescents than in infants, Canada adopted an immunization policy for youth aged 9-13, coordinated at the provincial, rather than national level.

This has important consequences as infants and young children remain susceptible to horizontal transmission from family members and peers. Furthermore, no national level systems are in place to identify children who miss grade level vaccinations due to within country relocation. Importantly, in contrast to adults who develop chronic infection after acute HBV exposure in just 1-5% of cases, 90% of infants infected with acute HBV will develop life-long chronic infection with its associated risk of life threatening liver disease.

Infant immunization against HBV can work in Canada. In 2001, British Columbia became the only province to offer universal infant vaccination, and since then, acute HBV incidence has declined more than in any other province in the country with rates consistently remaining below the national average. Many professional societies including CASL, the CLF, and CPS have strongly advocated for a unified national immunization program though the federal government has been slow to adopt these recommendations.

HBV Vaccination BC

Figure 1. Reported incidence of acute HBV in all ages in Canada, 1992-2007

The National Advisory Committee on Immunization should immediately recommend that the Public Health Agency of Canada within the federal government implement a unified nationwide infant immunization policy against HBV to protect infants and children who remain unnecessarily susceptible to this dreadful disease.

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5 Responses to “A Hepatologist’s Perspective: Why a Unified National Program for Infant Immunization Against Hepatitis B Should Be Implemented”

  1. schan78 Says:

    Great post. While I have no doubts that vaccines are a valuable and cost-effective tool, adopting at the national level can be extremely difficult. Thanks for sharing with us the annual incidence data of acute HBV in Canada. In addition, I think other measures of disease burden, such as mortality rates, hospitalization rates and disability rates by age group, could strengthen your campaign.

    Two questions that governments ask when they need to decide whether to adopt a National Policy are:
    1. Is the disease that the vaccine targets a public health priority?
    2. What about the characteristics of the vaccine?

    Regarding 1), different countries have different priorities and developed countries such as Canada face multiple health issues. Like with every country, I am sure resources are constrained. Regarding 2), how about the vaccine performance (efficacy and effectiveness), vaccine characteristics (doses, presentation, packaging, availability of supply) and its cost-effectiveness? Additional costs to consider when introducing a vaccine to the national immunization program include: vaccine administration, expansion of cold chain system, social mobilization activities to promote the vaccine, training of healthcare workers, public education, the cost of surveillance of disease and last but not least the costs to dispose of vaccine.

    The following document can be useful:
    http://www.who.int/immunization/programmes_systems/policies_strategies/vaccine_intro_resources/nvi_guidelines/en/

    Good luck with your campaign! Thanks.

  2. CaraD Says:

    This is such an interesting topic; having lived in the US my whole life, where the first Hepatitis B Vaccine is given to most infants before they even leave the hospital, I didn’t even realize it might vary in other developed countries. Trying to play devil’s advocate, perhaps the states in Canada that feel the immunization can wait until adolescence are assuming that all delivering mothers have been tested for the Hepatitis B Surface Antigen and that these high risk infants would receive a dose of HBIG? But the obvious reply to that is that not all mothers receive prenatal care, whether due to lack of access in proximity to a provider or mental unwellness, among other things. These high risk exposed infants would then fall through the cracks for HBIG administration and not even have the partial protection of the HBV.

    I also just remain confused about the rationale for waiting, especially if the studies in the article you linked to state that researchers in Senegal and New Calcedonia, among others, feel children who receive the vaccine earlier are more well-protected. According to our CDC, the vaccine should be effective (over 90% of cases) for life once the series is completed, with boosters being unnecessary unless someone is on hemodialysis or has a weakened immune system. ( http://www.cdc.gov/hepatitis/hbv/bfaq.htm )

    You’re absolutely right – a unified plan for vaccination should be reached.

    • agulamhusein Says:

      Thanks for your note – I agree, there is really not a good reason for this policy aside from the fact that it is somewhat “evidence based” in some ecologic level data but I think there were some important oversights. I think the working group felt that the absolute number of chronic HBV cases in infants and young children is small – which is probably true – but in my opinion, even one case of chronic infection in a child that poses such health risks is not acceptable – especially when a solution is available.

      You’re right that prenatal care helps screen mothers and helps with management of their infants but the kids that remain susceptible are those who are surface antigen negative and interact with family members and peers who are chronically infected prior to reaching adolescence. Immigration is a huge factor – there are lots of places in Canada that have a high rate of immigration from developed countries with endemic levels of HBV and chronically infected children interact with those who are immune/exposure naive.

      Appreciate your comments!

    • pamelamcdonaldblog Says:

      Cara- It’s not just those without prenatal care…I can tell you that the anti-vax movement has played a huge role in this. I know so many mothers who refuse that vaccine and try to be facetious…”oh yes, my newborn is going to be with a hooker shooting drugs in the next few years”. They don’t understand that the child can acquire it from bites at daycare/church/play date or from an adult who is infected. It is certainly a sign of a privileged, spoiled society when people refuse life saving interventions promoted by the medical community. There is a lot of misinformation and negative attitudes regarding the newborn HBV-vax and an equal amount of misinformation and unwarranted mistrust of HPV-vax for teens.

  3. lwang108 Says:

    Thank you for sharing this post! I have same misunderstanding that I’m supposed all new-born will take HBV vaccination in developed country mandatorily. However, the fact is just like Pamela told us: people refused the effective interventions from medical community before they suffer from the disaster.

    I want to share the story how HBV vaccine developed in China. HBV vaccine was first recommended for routine vaccination of infants in China in 1992, with the first dose to be administered within 24 hours of birth and subsequent doses at ages 1 and 6 months. However, because of the high cost, until 2002, infant vaccination occurred primarily in large cities of the wealthier eastern provinces in China.

    Infant hepatitis B vaccination was added to China’s National Immunization Program in 2002. With Global Alliance for Vaccines and Immunizations help, 5-year China-GAVI project covered 36% of Chinese child population in free HBV vaccine availability, targeting approximately 5.6 million children born each year. In 2005, a new vaccination regulation recommended HBV vaccine free in whole country.1

    From the development of HBV vaccine in China, I realize cost and policy regulation are two most critical factors for vaccine implementation in developing countries. Combined with your post, lack of education in vaccine knowledge plays an important role in developed countries. We public health practitioners are responsible for implementation of vaccination education in community and efforts in policy regulation. Thanks!

    1 http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5618a2.htm

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