Bounce. Bordetella pertussis is on the rise.
ORLANDO, Florida- - A vaccine against pertussis has lost its edge because new slightly different strains of the bacteria have emerged, say researchers. . The conclusion emphasizes the need to keep the date vaccinations
Pertussis or whooping cough is usually caused by Bordetella pertussis mainly strikes children, causing frightening episodes of cough, shortness of breath and sometimes brain damage or even death. Although it still kills 0,000 to 300,000 children worldwide each year, the disease has largely disappeared from developed countries through immunization of children. In the Netherlands, however, a country with a 96% vaccine coverage, hospitalizations for whooping cough exploded from several dozen in the late 1970s to over 500 in 1999. Other countries, including the United States, have also seen a rebound. So far, it is unclear why this happened.
thereFive years, a research team led by Frits Mooi at the National Institute of Public Health and the Environment in Bilthoven, the Netherlands, discovered a possible cause. Like many other countries, Holland uses a vaccine developed decades ago, which is killing Bordetella cells. But most recent patients were infected Bordetella strains that have mutations in the genes encoding the two key proteins thought to trigger the production of immunizing antibodies. Perhaps, the researchers hypothesized, changes in minutes make it less effective vaccine, which could explain the reappearance of the disease.
Now there is evidence to support the claim. When the researchers vaccinated mice with the Dutch vaccine, the animals are more susceptible to strains that had mutations that those who do not. Humans probably react the same way, says molecular biologist Audrey King, who presented the findings here on May 22 at a meeting of the American Society for Microbiology. The study shows that a new vaccine is needed that takes into account the changes, said the king.
Changes in Bordetella are a likely factor in the rebound of pertussis, accepts Henry Shinefield, co-director of the Kaiser Permanente Vaccine Study Center in Oakland, California. But there may be other, he said: For example, researchers recently realized that the immunity of a person decreases over the decades. Many seniors are now getting the disease, said Shinefield.
Related Sites
Learn more about the adjustments as a possible cause for Bordetella s' reemergence
information on Pertussis Centers for
pertussis information from the World health Organization Disease Control and Prevention
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