Pediatric Associates of the NW Blogs

Why would you vaccinate a baby for a sexually transmitted disease?

Jay S. Rosenbloom, MD, PhD
March 21, 2012 06:10PM

This is a question we often hear when discussing the Hepatitis B vaccine with new parents.

The simple answer? The vaccine is safe and prevents kids from being infected by a potentially deadly virus.

So why so young? It isn’t that we are worried about a newborn’s future sexual activity (yet), but rather the possibility the mother has the infection and does not know it.

The CDC estimates that more than 1,000,000 people in the US are chronic carriers of hepatitis B, and the majority denies having any risk factors for the disease.  That means that they were infected at some point and the virus remains active in their bodies but they don’t know about it.

If a baby does become infected with hepatitis B, it can be a lifelong, potentially fatal problem. Three out of four infants born to mothers with hepatitis B will become infected. That is unless they receive a dose of the vaccine.  If a newborn is given their vaccine in the first day of life it is 70-95% effective in preventing perinatal hepatitis B infection.

However, if a newborn contracts the virus in the birth process there is >90% likelihood they will become chronic hepatitis B carriers. Compare that to adults and the statistics are staggering– only 5% of adults will become chronically infected if they contract hepatitis B.

Chronic carriers can infect others and approximately 25% will die prematurely from cirrhosis or liver cancer.

So what is in the vaccine?  Since the mid 1980’s the vaccine has been made using baker’s yeast that have been given the gene for one hepatitis B surface protein.  There are no blood products used, no virus, no bacteria and nothing else that can cause an infection.

The Hepatitis B vaccine is safe and effective. It prevents a potentially deadly disease in infancy and protects young adults far beyond the time of vaccination (when they do become sexually active).