An unusual 2010 outbreak of whooping cough in Ohio that disproportionately affected adolescents led disease hunters from the US Centers for Disease Control and Prevention (CDC) to the surprising discovery that about a third of the cases were caused by infection with Bordetella holmesii and not Bordetella pertussis, the usual isolate among individuals with the characteristic symptoms of whooping cough.
Previously, isolated reports of B holmesii infection in patients with whooping cough–type symptoms had been described. But the data from the Ohio outbreak are the first to assess the incidence of B holmesii infections in a whooping cough outbreak, explained Loren Rodgers, PhD, an officer with the CDC's Epidemic Intelligence Service, who presented the data. In that outbreak, which affected about 900 individuals, testing confirmed that although most cases were caused by B pertussis, about a third were linked to B holmesii, and a few individuals were infected with both microbes.
Bridget M. Kuehn. Reports Highlight New Cause of Pertussis, Tickborne Illness, and Better Food Safety. JAMA. 2012;307(17):1785–1787. doi:10.1001/jama.2012.3925