Pennsylvania Rep. Mike Doyle said he tested positive for coronavirus despite being fully vaccinated and "taking the appropriate precautions."

Doyle, a Democrat, is at least the 11th member of Congress to announce a positive COVID-19 test since July amid an uptick of cases nationwide because of the highly contagious delta variant. Ten of the 11 members said they were fully vaccinated. 

"I'm feeling okay and having only mild symptoms, but I'll be quarantining in DC for a 10-day period, as the District of Columbia requires," Doyle said on Twitter.

In the months since January, no House or Senate member tested positive for coronavirus, which corresponded with the downward nationwide trend of cases and the uptick of vaccinations. But the tide turned in July in Congress with a new outbreak of cases that reflected the nationwide increase in COVID-19 transmission that is still on a steady rise.

Other recent cases of congressional coronavirus include Reps. Barry Moore, R-Ala., Troy Nehls, R-Texas, Vern Buchanan, R-Fla., Clay Higgins, R-La., Ralph Norman, R-S.C., Sharice Davids, D-Kan., as well as Sens. Lindsey Graham, R-S.C., Roger Wicker, R-Miss., Angus King, I-Maine, and John Hickenlooper, D-Colo.

All the members said they were vaccinated, except for Higgins who did not disclose his vaccination status.