Changes in Hospital Orders Increase Pertussis Immunization Rates Researchers Find 69% Rise in Vaccinations among New Mothers


Changing the hospital orders for women who have just delivered a child led to a 69% increase in the new mothers’ pertussis vaccination rate, providing protection for themselves and their newborns against the disease, commonly known as whooping cough, according to a study in the March issue of the American Journal of Obstetrics & Gynecology.

Sylvia Yeh, MD, a Los Angeles Biomedical Research Institute (LA BioMed) lead researcher and corresponding author of the study, said it is the first to compare immunization rates among two hospitals: one which followed standard procedures and another that implemented a physician opt-in order initially and then a standing order for new mothers to receive the tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine (Tdap) before discharge.

The researchers found that the postpartum Tdap vaccination rate at both hospitals was zero at baseline. Implementing the opt-in order increased the immunization rate to 18%. Implementing the standing order caused an even larger increase in vaccinations, raising the rate to 69%. At the hospital following standard procedures, there were no postpartum Tdap vaccinations.

“Vaccinating mothers of newborns holds the promise to reduce the risk of whooping cough among infants,” said Dr. Yeh. “Our study found a simple change in a hospital’s standing orders can make a profound difference in the immunization rates of mothers of newborns and provide vital protection to their babies and the rest of their families.”

The Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) recommends Tdap immunization for all children at the ages of 2, 4, 6 and 15-18 months of age. As a result, infants under the age of six months are susceptible to whooping cough infections because they have not received all the necessary doses of the vaccine.

In one CDC study, the mother was identified as the source of pertussis infection in 32% of infants surveyed. In the U.S., 13 infants who were 3 months old or younger died of pertussis in 2012. Since 2006, the ACIP has recommended Tdap vaccinations for anyone who comes in contact with infants.

Since the study’s completion, ACIP has updated its recommendation to say women should receive Tdap vaccinations, if they don’t already have them, in the latter part of their second trimester or during their third trimester of pregnancy. Despite the new recommendation, studies found less than 3% of unimmunized pregnant women receive a Tdap vaccination.

“Based on our study, hospitals could greatly improve immunization rates and lower risks for newborns by having standing orders for new mothers to receive Tdap vaccinations if they have not received them during pregnancy,” Dr. Yeh said. “The mothers are likely to agree to be vaccinated if they receive information on the importance of being immunized to protect their children.”

This research was supported by CDC Grant No. 5U01-IP000192. The conclusions represent the authors’ views and do not necessarily represent the CDC’s views. In addition to Dr. Yeh, the study’s authors are: Drs. ChrisAnna Mink and Kenneth M. Zangwill from LA BioMed; Dr. Matthew Kim from Cedars-Sinai Medical Center and the David Geffen School of Medicine at UCLA; Dr. Scott Naylor from Department of Perinatal Medicine, Providence Little Company of Mary Hospital, and Dr. Norma J. Allred from the Immunization Services Division, National Center for Immunization and Respiratory Diseases, CDC.