By JULIA JACOBO, BENJAMIN SIEGEL and ALLISON PECORIN, ABC News

(WASHINGTON) — Five more members of Congress have tested positive for COVID-19 or been exposed to the deadly virus within the last week.

At least 27 members of Congress have become infected with the virus since the spring. This number does not include presumed positive cases or members who tested positive for antibodies.

Since Friday, the lawmakers who tested positive or have been exposed to the virus include: Rep. Cheri Bustos, D-Ill., Rep. Tim Walberg, R-Mich., Rep. Mark Pocan, D-Wis., Rep. Don Young, R-Arkansas, Rep. Debbie Lesko, R-Ala., and Sen. Chuck Grassley, R-Iowa.

Bustos and Walberg both experienced “mild” symptoms, according to statements they posted on Twitter. Young was hospitalized over the weekend and is now recovering at home, confirming on Twitter that he is “alive.”

Pocan is in quarantine after his mother tested positive for the virus and Lesko is isolating after an aide tested positive for COVID-19. Grassley did not say how he was exposed to the virus in a statement released on Twitter.

The additional infections on Capitol Hill come as nearly every state experiences an uptick in cases, filling hospital intensive care units almost to capacity.

Sen. Rob Portman announced Wednesday that he will participate in the Phase 3 clinical trial for Johnson & Johnson’s COVID-19 vaccine, calling vaccine development the “single most important part” of COVID-19 response.

“I look at it as a way I can play a small role in supporting our country’s health care response to this pandemic,” Portman said. “I hope that my announcement today will encourage others to feel confident in participating in vaccine clinical trials being conducted across this country. I also hope it will reassure people about the safety and effectiveness of vaccines once they have gone through the trials and FDA approval process.”

Mask wearing remains a contentious subject on the Senate side, where masks are advised and worn by most members but are not required as they are in the House of Representatives.

Senate Minority Leader Chuck Schumer began his floor remarks Tuesday reminding members to wear a mask at all times on the Senate floor.

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