Lack of Association Between Hepatitis B Birth Immunization and Neonatal Death: A Population-Based Study From the Vaccine Safety Datalink Project. Eriksen EM, Perlman JA, Miller A, Marcy SM, Lee H, Vadheim C, Zangwill KM, Chen RT, DeStefano F, Lewis E, Black S, Shinefield H, Ward JI. The Pediatric Infectious Disease Journal 2004;23(7):656-662.
Explanatory note: Hepatitis B vaccine (HBV) is widely administered to newborns both in the United States and worldwide. Prior studies have refuted associations between vaccines and unexplained deaths (such as sudden infant death syndrome). There has been no observed relationship between the early HBV immunization and serious adverse events. However, because healthy infants are more likely to receive HBV at birth than are sick infants, this large population study was designed to look for any potential association between HBV given at birth and death (both expected and unexpected deaths) among more comparable groups of HBV-vaccinated and unvaccinated newborns.
Is there an association between newborn immunization with hepatitis B vaccine and death during the first month of life?
This study included all children born at Southern and Northern California Kaiser Permanente Health Plans from 1993 to 1998.
The researchers identified all the children who died under 29 days after birth and determined which ones were vaccinated against hepatitis B. They also reviewed the circumstances and causes of the deaths, categorizing deaths as “expected” or “unexpected” without knowledge as to whether the child had been immunized or not.
They also performed a detailed review of all the deaths among the vaccinated newborns to determine whether experienced clinicians could find an explanation as to whether HBV might have played a role in the death.
There were 1,363 neonatal deaths in the population of 361,696 live births studied—or 3.8 neonatal deaths/1000 live births. During the five years of the study, 67% of the children received HBV at birth, but only 72 (5%) of the neonates who died were HBV-vaccinated at birth.
The study found no significant difference in the proportion of HBV-vaccinated and unvaccinated neonates dying from either expected or unexpected causes.
Also, it did not find a plausible causal or temporal relationship between HBV vaccination and death for the 21 of 22 vaccinated infants who died unexpectedly. One infant could have had a serious allergic reaction although this would have occurred much later after vaccination than is usual for this type of reaction.
As expected, this study found that newborns with low birth weight or other serious conditions were much less likely to receive HBV than were neonates who appeared healthy at birth.
This study did not demonstrate a relationship between Hepatitis B vaccination at birth and death during the first 29 days of life.
Most children who die within the first month of life have serious conditions that are recognized at birth or shortly afterwards; these children are less likely to receive a birth dose of HBV. To control for this, these investigators performed a careful stepwise analysis of the expected and unexpected causes of death among a large population of newborns. They were unable to show an effect of the birth dose of HBV on death during the first month of life.