World needs a better pertussis vaccine, expert argues

A pediatric infectious disease expert made the case that the world needs a better pertussis vaccine.

“I don't know that everyone appreciates that pertussis is in the top 10 causes of death for children worldwide,” C. Buddy Creech, MD, MPH, president of the Pediatric Infectious Diseases Society and director of the Vanderbilt Vaccine Research Program at Vanderbilt University Medical Center, said at the St. Jude/PIDS Pediatric Infectious Diseases Research Conference.

“We have a great vaccine,” said Creech, a Healio Pediatrics Peer Perspective Board Member. “It's not great enough.”

Pertussis, commonly known as whooping cough, is primarily spread through droplets containing the bacterium Bordetella pertussis.

The CDC recommends that children younger than age 7 years receive five doses of DTaP given at different intervals — unless they are unable to receive an acellular pertussis-containing vaccine, in which case the CDC recommends using the DT vaccine.

DTaP produces fewer side effects and has a lower concentration of diphtheria and pertussis toxoids than the old, whole-cell vaccine DTP. Given on schedule, it protects 98% of children within a year following the last dose and around 71% of children 5 years after the last dose, according to the CDC.

Researchers from the CDC, WHO and UNICEF reported late last year that 25 million children worldwide were unvaccinated or incompletely vaccinated with DTaP in November.

Creech emphasized that pertussis has “an incredibly high burden of disease around the world, even though it is on the extended program for immunization in nearly every country.”

“We've seen a wonderful decline in these diseases over time as vaccine coverage has reached maybe 85% or so in the United States,” Creech said. “But if you look at the cases of pertussis, we still have about 140,000 to 150,000 cases (globally) that are diagnosed each year, and we do a terrible job diagnosing pertussis. We don't think about it early enough, even though in some of the older studies from the 90s, we know that in some studies, 30% of cough that lasts for more than 2 weeks is due to pertussis. And yet we don't always look for it in those individuals.”

Creech suggested altering the DTaP vaccine to “add some things to it or adjuvant it in such a way that it begins to work a little bit more like the whole-cell vaccine does.”

“Or we could take whole-cell approach and attenuate it even further, maybe give it through the mucosal route and maybe that would look more like an acellular vaccine, at least as relates to safety, but maintain that immunogenicity,” Creech said.

“What we want our vaccines to do is mimic the response to natural infection if the response to natural infection clears that particular pathogen, and so we've got to use large animal models ... and we've got to study humans in order to make that happen,” Creech said.

References:

CDC. Diphtheria, tetanus, and pertussis vaccine recommendations. https://www.cdc.gov/vaccines/vpd/dtap-tdap-td/hcp/recommendations.html. Last reviewed Sept. 6, 2022. Accessed March 6, 2023.

Creech CB. New approaches to building better pertussis vaccines. Presented at: St. Jude/PIDS Pediatric Infectious Diseases Research Conference; March 1-3, 2023; Memphis, Tennessee.