Comparing Schedules for Infant Vaccines

Pneumococcal vaccine schedule differences not seen after final booster shot for infants

/ Author:  / Reviewed by: Robert Carlson, M.D Beth Bolt, RPh

(RxWiki News) According to researchers behind a new study, pneumococcal disease is one of the leading vaccine-preventable causes of childhood death in the world.

The researchers also reported that vaccination schedules to protect children from this serious disease differ between countries in regard to age at vaccinations, number of doses and the time between doses.

This new study examined four different pneumococcal vaccination schedules and found that after the final booster shot, no major difference existed between them.

"Talk to your child's pediatrician about vaccinations. "

According to the US Centers for Disease Control and Prevention (CDC), pneumococcal disease is caused by the bacterium Streptococcus pneumoniae and can lead to a number of complications that range in seriousness, from ear and sinus infections to pneumonia and infections of the bloodstream.

The pneumococcal conjugate vaccine (PCV13) is used to protect children against the 13 types of pneumococcal bacteria that tend to cause the most severe pneumococcal disease outcomes in children, says the CDC.

In this new study, a team of researchers led by Judith Spijkerman, MD, of the University Medical Centre in Utrecht, the Netherlands, attempted to explore if there was a difference in effectiveness between different vaccination schedules for pneumococcal disease.

To do so, Dr. Spijkerman and team randomly assigned 400 healthy infants in the Netherlands to one of four different primary vaccination groups. One group received PCV13 at ages 2, 4 and 6 months (2-4-6), one group at 3 and 5 months (3-5), one group at 2, 3 and 4 months (2-3-4) and the last group received PCV13 at ages 2 and 4 months (2-4). 

All of the participating infants were given a PCV13 booster dose at the age of 11.5 months. 

Blood samples were collected from the infants four times: one month after the primary vaccination series, at 8 months of age, before the booster dose and one month after the booster dose. The samples were examined for the presence of pneumococcal antibodies to protect against the 13 types of pneumococcal bacteria blocked by PCV13.

When looking at the samples taken at the end of the study (one month after the booster dose), the researchers found no major differences between the samples in the majority of their comparison points (70 out of 78).

However, when looking at the samples from earlier in the study, they did find some differences between the different schedules and specific types of pneumococcal bacteria (called serotypes).

In the samples taken one month after the primary vaccination series, at 8 months of age and before the booster shot, the 2-4-6 group faired better for several serotypes than the other groups.

"The 2-4-6 schedule was superior compared with the 3-5, 2-3-4, and 2-4 schedules for 3, 9, and 11 serotypes, respectively," the study authors wrote.

The authors noted that these differences lasted until the booster dose was given, at which the results seemed to even out among all of the vaccination schedules. 

"The use of 4 different PCV13 immunization schedules in healthy term infants resulted in no statistically significant differences in antibody levels after the booster dose for almost all serotypes," Dr. Spijkerman and team concluded. "The choice of PCV schedule will require a balance between the need for early protection and maintaining protection between the primary series and the booster."

This study was published on September 3 in the Journal of the American Medical Association (JAMA).

Two of the researchers involved reported receiving research grants and various fees from the pharmaceutical companies Pfizer and GlaxoSmithKline. Pfizer provided some of the vaccines used in this study.

Review Date: 
August 30, 2013
Last Updated:
September 3, 2013