The Democrat from Oak Park was vaccinated in the spring. He began experiencing symptoms late last week, self-isolated and tested positive, according to a statement. His office said "contact tracing was implemented."
"I’m even more grateful to be vaccinated, given how mild my symptoms have been," Harmon said in a statement. "I encourage everyone to get vaccinated and also to not let their guard down as we try to get back to normal."
Harmon, an attorney, was elected senate president last year. He was first elected to the Illinois Senate in 2002.