Why Your Baby Gets the Hepatitis B Vaccine at Birth
- Dr. Amy Voelker
- 3 days ago
- 3 min read
As parents, we do everything we can to protect our children — from installing baby gates to choosing the best car seat. But one of the most important protections starts right at birth, often before we even leave the hospital: the Hepatitis B vaccine.
What is Hepatitis B, Anyway?
Hepatitis B is a serious infection that affects the liver, an organ that helps your child digest food and clean harmful substances from their body. When someone gets hepatitis B, their liver becomes inflamed, which can cause symptoms like:
Yellowing of the skin or eyes (jaundice)
Tummy pain, nausea, and vomiting
Fever and fatigue
Dark-colored urine
Some people recover fully, but others — especially babies and young children — can develop long-term complications like:
Liver damage (cirrhosis)
Liver cancer
Even death
How Is It Spread?
Hepatitis B is often called the “silent infection” because many people don’t even know they have it — and can still pass it on. The virus lives in blood and certain body fluids, and it’s surprisingly easy to catch:
Through tiny amounts of blood — even from a shared toothbrush or washcloth
From an infected mother to her newborn during birth
Through cuts or scrapes when kids share personal items
In older children and adults, it can also be spread through sexual contact or needle use
Because it's so contagious and hard to detect early, even casual contact can be enough to spread it.
Why Do Babies Get the Vaccine?
Years ago, the vaccine was only given to high-risk groups like healthcare workers. But this approach didn’t reduce the number of infections. So in 1991, the CDC recommended universal vaccination for all newborns.
Since then, something amazing has happened:
Hepatitis B infections in children under 19 have dropped dramatically.
In fact, because of routine vaccination at birth, we’re on track to eliminate hepatitis B in the next generation. Giving the vaccine at birth is also essential because:
It protects babies born to mothers who may unknowingly carry the virus.
It protects against infections that can be picked up through everyday contact.
Is the Vaccine Safe?
Yes — and it’s very well-studied. Like all vaccines, it comes with some possible (usually mild) side effects, such as:
Redness or soreness at the injection site
A low-grade fever
Severe allergic reactions (anaphylaxis) are extremely rare — about 1 in 600,000 doses — and treatable.
Now compare that to the real risks of hepatitis B:
Around 2,000 people in the U.S. die each year from complications
Another 22,000 are chronically infected, facing lifelong risks of liver disease
Aside from COVID-19 and the flu, hepatitis B is the deadliest vaccine-preventable virus in the U.S. today.
When Does My Child Get the Vaccine?
The first dose is given at birth, usually within the first 24 hours. It’s part of a 3-dose series:
Dose 1: At birth
Dose 2: At 1–2 months
Dose 3: At 6 months or later (final dose must come after 6 months of age)
