Evidence of Vaccine-Resistant Pertussis Found

Evidence of Vaccine-Resistant Pertussis Found

In a letter published in February in The New England Journal of Medicine, researchers from the United States Centers for Disease Control and Prevention (CDC), St. Christopher’s Hospital for Children in Philadelphia, and Raritan, New Jersey-based Janssen Research and Development cite evidence that strains of Bordetella pertussis—the bacteria that causes whooping cough—have adapted to acellular vaccines. This could account for recent figures from the CDC indicating that 2012 was the worst year for pertussis since 1955.

The research results, which parallel similar findings documented in Japan, France, and Finland, are derived from the genetic analyses of 12 isolates of B. pertussis. Of the isolates, cultured from 12 children hospitalized in Philadelphia for pertussis in 2011 and 2012, 11 showed signs of immunity to pertussis vaccines. The bacteria infecting these 11 children were found to lack a crucial protein—pertactin—that is present in the vaccine. The mutations were also found to differ from those discovered in the French study.

The researchers state that their findings represent the first reported occurrence of pertactin-negative variants of B. pertussis in the US. They recommend that more studies on isolates from different locations throughout the country should be conducted to verify if their results signify an isolated event, or a widespread development.

While scientists continue to investigate the resurgence of pertussis cases, the CDC advises that vaccination is the best way to prevent illness.