We've reported on the evolution of whooping cough before. Researchers have found evolved pertussis, as whooping cough is scientifically known, in Finland, France, Italy, Japan and the U.S. As we previously reported, the evolved bacteria don't seem to be more dangerous than their predecessors. Nevertheless, the U.S. Centers for Disease Control and Prevention are keeping an eye on whooping cough's evolution. It could help explain another recent pertussis phenomenon: The newest pertussis vaccines seem to wear off much faster than older ones, leaving kids vulnerable at age 8 or 10 unless they get booster shots.
In Australia, researchers from several universities and hospitals examined samples of pertussis dating back to 1997. What they saw happening there mirrored what's happened in the U.S.