How Common is Hep B in Infants?
How Might an Infant Contract Hepatitis B?
Of the 30 cases of infants contracting Hep B in the United States every year, the vast majority get the virus from an undiagnosed birth parent during the birthing process.
If you or whoever is carrying your baby has Hepatitis B, then vaccination at birth is essential. Vaccination (along with treatment with hepatitis B immune globulin) can prevent 85-95% of transmission of hep B from a hep-B positive birth parent to their infant.
What about Infants with Hep B Negative Parents?
So… if infants with Hep B negative parents are so unlikely to get the virus, why do we vaccinate for hep B at such an early age?
The Hepatitis B Initiative
Since initiating infant and adult vaccination programs, better donor blood screening, needle exchanges, safer-sex education, and various other public health programs aimed at decreasing Hepatitis B infection rates in the US, the rate of acute Hep B infection has fallen from it’s all-time high of 25,000 cases per year in the mid 1980’s to under 5,000 cases per year today(mostly in adults - there are around 30 cases per year reported in infants, 30 more in kids under 6, and around 90 per year in older kids and adolescents). This dramatic decrease in acute infection rates is pretty awesome, because Hepatitis B, like I said, is a very bad disease.
So Why Do Some Parents Decide Not to Vaccinate for Hepatitis B?
A big part of our immune system is our T-cells. There are two main types of responses our T-cells can have: one is for killing bugs, such as bacteria and viruses (called a Th1 response), while the other is for mounting an allergic-type response (called a Th2 response). A Th2 response is often at work with conditions like seasonal allergies, food allergies, asthma, and eczema.
The infant immune system has a hard time responding to bacteria and viruses (the Th1 response). It’s easier for a baby’s immune system to respond by mounting Th2 response. There are some theories that giving infants vaccines before 2 years of age can increase the Th2 response even more, pushing their immune system towards more of these reactive conditions such as allergies, eczema, and asthma. There isn’t currently a lot of evidence to support or deny this theory.
However, there have been some informal surveys of parents of both vaccinated and unvaccinated kids comparing rates of allergies, asthma, and autism. The most famous of these is an ongoing survey of around 12,000 kids by a very decidedly anti-vaccination German website impfschaden.info (the German counterpart to vaccineinjury.info). In those surveys, parents of unvaccinated kids reported significantly lower rates of asthma, allergies, autism, and ADHD, as compared to kids who were vaccinated.
Some parents chose not to vaccinate their kids before age two, just to avoid any risk of increasing their child’s chance of developing these and other allergic or inflammatory-type conditions.
In addition to concerns over allergies, there are some specific risks associated with the hepatitis B vaccine.
Specific Risks Associated with the Hepatitis B Vaccine
While the newborn Hep B vaccine is generally given by itself, an infant on the normal CDC schedule will get 5 different shots at their two month visit, three of which most likely contain aluminum (HIB, Pc, and DTaP). This can add up to as much as 1225 mcg aluminum in that single visit. There are few human studies that show the safety of injected aluminum at these levels.
- Autoimmune Disease Risk. Hepatitis B vaccine has a relatively high association with development of autoimmune disease, especially lupus and multiple sclerosis. There are hundreds of documented cases of this, but these have all been in adults. Infants rarely develop autoimmune conditions, though long-term autoimmune risk in people vaccinated as infants is harder to predict. That said, almost any infection (vaccine, virus, bacteria…) could theoretically lead to an autoimmune disease.
Other adverse effects reported after Hepatitis B vaccination include Stevens-Johnson syndrome, nerve dysfunction or paralysis, seizures, and inflammation of the blood vessels or the optic nerve.
Who Should Get the Hep B Vaccine, then?
A popular and quite reasonable option for parents who want their kids to be protected against Hepatitis B is to wait till their child is at least two years old or even an adolescent before giving the vaccine. This ensures that the child’s immune system is fully mature before receiving the vaccine, and still offers protection before the child is likely to engage in any high risk behavior.