Conditional univariable logistic regression models predicted that concurrent diabetes, asthma, or COPD, use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and prior use of antibiotics within 1 month increased the risk for a pertussis diagnosis; history of influenza vaccination was associated with reduced risk for a pertussis diagnosis (Table 2). The gene discussed is ACE; the disease is pertussis.