Bessler, who is a law professor at the University of Baltimore, said during a Tuesday interview with NBC News that he originally felt great and was teaching classes before falling ill on March 12.
“It just suddenly hit me and I had a fever, and that fever just lasted for days and days,” Bessler, 52, told NBC correspondent Stephanie Gosk.
Klobuchar, 59, was in Washington, D.C., working to pass a massive coronavirus relief bill while Bessler self-isolated in his apartment.
The former presidential candidate told Gosk she wasn’t nervous until Bessler’s shortness of breath became noticeable in their phone conversations — and he began coughing up blood.
Bessler checked himself into a hospital in Virginia where X-rays initially revealed he had pneumonia, a serious complication of the virus, and low oxygen.
“This is not a cold,” he told NBC. “You don’t get pneumonia when you get a cold, and you don’t end up in the hospital on oxygen when you get a cold … this is really a serious thing.”
The test results confirming his diagnosis of the new coronavirus, which causes the respiratory disease COVID-19, came in days later.
Health officials have urged people to avoid public and only go outside when necessary in a social distancing strategy to slow new infections while researchers work on treatments and a vaccine.
Because the virus is so infectious, patients are isolated from their loved ones during treatment.
“If it was normal circumstances, I would be there with him, every part of every day,” Klobuchar told PEOPLE while her husband was hospitalized. “But I can’t, and so you delve into your work, and then I talk to him. My daughter gives me reports, she talks to him as well. We share information and then I text with the doctor [and] talk to the doctors about three or four times a day.”
Klobuchar told PEOPLE that she and her husband had not been in physical contact in recent weeks before his diagnosis and so she was not being tested for the virus.
Bessler has since recovered and was reunited with Klobuchar and daughter Abigail in their Minnesota home.
The law professor told Gosk this week he plans to donate blood, too, to help researchers study the virus.
“But he’s not contagious anymore,” Klobuchar said during the video interview as she leaned in to hug her husband. “At least that’s what the doctor said!”