Before the whooping cough vaccine came into routine use in the 1940s, the infection killed around 4,000 people a year in the US: in 2011, it killed 13 people.  However, unlike with the resurgence of measles, the revival of whooping cough has very little to do with the vaccine.

“We don’t think those exemptors are driving this current wave,”
– Anne Schuchat, director of the National Center for Immunization and Respiratory Diseases.

It’s actually worse news than it sounds:  almost three-quarters of kids aged between 7 to 10 who caught whooping cough in Washington State had been fully vaccinated.

The effect of the vaccine “…wanes more quickly than we expected…We’re trying to understand why.”
– Stacey Martin, epidemiologist, The Centers for Disease Control and Prevention.

The vaccine’s effectiveness seems to decline quickly after the vaccine’s final dose.  Adults and teens who are inoculated can harbour the infection for years.  Until a better vaccine is developed, the CDC is urging adults and adolescents to get a booster shot, but as of 2010, only about 8 percent of adults had gotten one.