"I'm in their house. I actually have the third story to myself," Underwood said of quarantining at Randolph's family home. "They drop meals off and water off when I need it."
UPDATE 1:50 p.m.on 3/24/2020:
Underwood took to his Instagram Monday afternoon to share another health update.
Captioning a photo of himself in bed, the former professional athlete wrote, "The last few days were rougher than I expected. The most prominent symptoms are my cough, night sweats and shortness of breathe. [sic] Breathing is challenging, the best way to describe it is feeling like I only have access to 20% of my lungs."
"I can only imagine how people with pre-existing health conditions feel with this," he continued, adding that he's been journaling while sick. "I'm currently on hydroxychloroquine, Z-Pak and last night the doctor prescribed an inhaler, also. I'm hopeful that they are starting to work! This morning was the first time that I've felt any real type of improvement since the beginning of this. Im hopeful that I've turned the corner and will be back to 100% soon."
Underwood also spoke more about staying with Randolph's family, revealing that the Health Department had called "to make sure we understood timing and what to do."
"When they make food they make an extra plate and drop it off and have been checking on me regularly to make sure I am comfortable and breathing!" he explained. "They have been amazing and have been taking great care of me. Stay positive people...We got this!"
On Tuesday, Underwood offered more detail about quarantining with his girlfriend and his family, telling People none of them have presented any symptoms.
"I'm taking the home isolation very seriously," he said. "I'm isolated to a room and Cassie brings me my food with gloves and a mask on."
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"It's been gnarly these past few days," Underwood told Seacrest. "Nothing that I'd ever expected, but I'm doing okay so far."
Talking about his original symptoms, the former NFL player explained, "I just assumed I had the flu. At the beginning of it, [I had] headaches, body aches and then it progressively turned pretty quickly."
When asked what prompted him to get tested Underwood replied, "I woke up one morning and the whole bed was just soaking wet...I knew something was off at that time."
He continued, "And then when I got up in the morning I had to sit down to go to the bathroom because I couldn't walk to the bathroom without being exhausted."
"My symptoms were, in my opinion, severe enough to go get tested to figure out what was going on," he added. "I was very lucky to find a doctor here in Orange County. I just went to their website. I called them myself, scheduled a consolation, because you have to get approved to even get qualified for the testing out here...I went in and got the test."
Underwood, who starred as The Bachelor for Season 23 last year, stressed the importance for people of all ages to stay home, even if they may think they are healthy.
"It affects everybody -- not just elderly or people with preexisting conditions," he said. "I felt like I'm a healthy individual... and this thing sort of crippled me in the last few days."
Underwood said he's on "two medications" President Donald Trump has spoken about. (Trump has praised the use of anti-malaria drugs chloroquine and hydroxychloroquine -- the latter combined with the antibiotic azithromycin he called "one of the biggest game changers in the history of medicine." While health experts urge caution, as Nigeria reported 2 cases of poisoning due to chloroquine.)
"I'm praying those kick in," Underwood continued. "I think I'm on Day 3 of those. I have read that the second week is typically the hardest."
The ABC star said the "scary part" is he doesn't know "how, when or where" he contracted the coronavirus. "I don't know what stage I'm at," Underwood admitted.
Underwood also spoke about how he's self-isolating at his girlfriend Cassie Randolph's home in Huntington Beach, California.
"I'm in their house. I actually have the third story to myself," he said. "It's the smartest thing and the best thing for the whole entire family. And I'm lucky enough that there's a little balcony so if I need fresh air, I can step out and get fresh air."
"They drop meals off and water off when I need it," he added. "Staying away and trying to keep them healthy."
On Friday, Underwood revealed he had tested positive for COVID-19 and urged everyone to practice social distancing and shelter at home.
Captioning an Instagram video, the reality star explained, "we got this. I tested positive and I have been following all of the social distancing rules since last week. My symptoms started a few days ago, I was tested and just received my results today."
"For anyone out there that is hesitant to self quarantine... please do yourself and your loved ones a favor and stay home," he continued. "We will all beat this and come out stronger on the other side. I'll keep you posted, Love y'all."
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