Protection against whooping cough waned during the five years after fifth dose of DTaP

September 12, 2012

OAKLAND, Calif. − Protection against whooping cough (also called pertussis) waned during the five years after the fifth dose of the combined diphtheria, tetanus, acellular pertussis (DTaP) vaccine, according to researchers from the Kaiser Permanente Vaccine Study Center. The fifth dose of DTaP is routinely given to 4- to 6-year-old children prior to starting kindergarten.

The study appears in the current online issue of the .

This is the first study to specifically focus on the large population of highly vaccinated children who had exclusively received DTaP vaccines since birth and for whom enough time had passed since their fifth dose that DTaP vaccine waning could be measured, said the researchers. They explained that the study period included a large outbreak that occurred in California during 2010. Researchers examined the relationship between time since vaccination with the likelihood of a positive pertussis test in the Kaiser Permanente Northern California population, which includes 3.3 million members in an system with and a central laboratory.

Researchers compared 277 children, 4 to 12 years of age, who were positive for pertussis with 3,318 children who were negative for pertussis and separately with 6,086 matched controls. They assessed the risk of pertussis in children from 2006 to 2011 in California relative to the time since the fifth dose of DTaP and found that protection from pertussis after the fifth dose of DTaP vaccine wanes more than 40 percent each year. The amount of protection remaining after five years depends heavily on the initial effectiveness of the fifth dose of DTaP, according to Nicola Klein, MD, PhD, co-director of the Kaiser Permanente Vaccine Study Center and the lead author of the study.

If the initial effectiveness of the fifth dose of DTaP was 95 percent, the effectiveness of DTaP would decrease to 71 percent after five years. Whereas if the initial effectiveness was 90 percent, it would decline to 42 percent after five years, explained the researchers.

"The findings suggest that whooping cough control measures may need to be reconsidered. Prevention of future outbreaks may be best achieved by developing new pertussis–containing vaccines or reformulating current vaccines to provide long-lasting immunity," said Klein.

"That said, the DTaP vaccine is effective and remains an important tool for protection against for children and the communities in which they live, and following current CDC recommendations remains important."

The CDC currently recommends five DTaP shots for . The first three shots are given at 2, 4, and 6 months of age. The fourth shot is given at 15 through 18 months of age, and a fifth shot is given when a child enters school, at 4 through 6 years of age.

The first was developed in the 1930s and was in widespread use by the mid-1940s, when pertussis vaccine was combined with and tetanus toxoids to make the combination whole cell pertussis vaccine DTP. In 1991, concerns about DTP safety led to the development of the acellular pertussis DTaP vaccines that are associated with fewer side effects. DTaP vaccines have completely replaced the whole cell DTP vaccines in the United States as well as in many countries around the world.

Explore further: Washington pediatricians receive regular requests for alternative child immunization schedules

Related Stories

Recommended for you

The 'love hormone' may quiet tinnitus

September 23, 2016

(HealthDay)—People suffering from chronic ringing in the ears—called tinnitus—may find some relief by spraying the hormone oxytocin in their nose, a small initial study by Brazilian researchers suggests.

Bile acid uptake inhibitor prevents NASH / fatty liver in mice

September 21, 2016

Drugs that interfere with bile acid recycling can prevent several aspects of NASH (nonalcoholic steatohepatitis) in mice fed a high-fat diet, scientists from Emory University School of Medicine and Children's Healthcare of ...

New therapeutic target for Crohn's disease

September 20, 2016

Research from the Sanford Burnham Prebys Medical Discovery Institute (SBP) identifies a promising new target for future drugs to treat inflammatory bowel disease (IBD). The study, published today in Cell Reports, also indicates ...

Mosquitoes, Zika and biotech regulation

September 19, 2016

In a new Policy Forum article in Science, NC State professor Jennifer Kuzma argues that federal authorities are missing an opportunity to revise outdated regulatory processes not fit for modern innovations in biotechnology, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.