RICHMOND, Va. – Whooping cough cases are increasing in Virginia, with seven outbreaks reported this year.
As of June 30, state health officials say there were 189 cases statewide. That's more than double the 87 cases during the same period in 2010.
Whooping cough, also called pertussis, is a highly contagious bacterial infection that causes severe coughing fits.
Chesterfield Health District director Dr. Parham Jaberi says there's no single factor that would explain the increase in cases. But adults vaccinated when they were younger may have lost some immunity.
Epidemiologist Jonathan Falk with the Central Shenandoah Health District says the pertussis vaccine's effectiveness wanes about five to 10 years after it's received.