She joins a growing number of famous faces who claim to have tested positive for the respiratory illness, including actors Tom Hanks, Rita Wilson and Idris Elba as well as Bravo's Andy Cohen and "Bachelor" star Colton Underwood.
In a lengthy post, Mazar, 55, assured fans she's doing well.
"I AM OK," she wrote.
Mazar says her husband and two teenage daughters battled an "odd bug" about a month ago. Symptoms included low-grade fever, headache, sore throat, body aches, ringing ears and a dry cough.
The actress says, "It cleared up quickly. Seasonal I thought? But it felt unusual/different..."
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I have just tested positive for Covid-19.I AM OK! About a month ago my entire home(husband and two teen daughters) got an odd bug- Low grade fever,headaches,sore throat,body aches,ears ringing and a dry cough.It cleared up quickly.Seasonal I thought?but it felt unusual/different... Two weeks later,March 15th,I woke up with all those same symptoms but super intense body aches,and 102.4 fever.I figured maybe I got the flu or..Corona?😬 I had had cocktails the evening prior,and smoked a few cigarettes. I figured I had jacked my immune system from having a fun night with friends.I called a doctor/friend to ask if I could get the Covid-19 test on 3/16.He said NO,I didn’t meet the criteria.I hadn’t recently traveled out of the country&I hadnt been with someone who had actually tested positive.I found this kind of a CRAZY criteria for a NY’er as I had taken the subway,gone to the theater,the grocery store,the pharmacy,hair salon,etc.I was the Mom who was trying to prepare the home and get supplies&bleach wipes,dry goods.extra food etc. Because we have Italian family in Italy and we follow the news closely,my biggest panic was why were they not closing schools in NYC &forbidding movement outside the home without permission,like China and all of Europe? Prospect Park yesterday,i hear was jumpin’! A friend told me that CityMD/Urgent Care in my neighborhood had test kits,which appealed to me as I wanted to stay away from the hospital. I went on 3/17.First I was tested for the flu-which was negative.Then they tested me for Covid-19. I was sent home and told to quarantine myself until I had results,which would take 3-7 days(in S.Korea it takes two hours) Well..today is day 5 and I just found out.Im hoping I’ve been through the worst of it already.Its very “morphy”.One day I feel crappy and the next I’m normal.Today my lungs are heavy,but I’m tough. I can breath,and I’m going to heal here,in my own home!My family is under quarantine for 14 days.They have no symptoms.I think we all had it possibly already?Who knows. Anyhow,stay home people!Protect yourselves&your loved ones.Build up your immune systems.Good Luck&God Bless us all! #alonetogether #physicaldistancing #stayhome
A post shared by Debi Mazar (@debimazar) on Mar 21, 2020 at 1:01pm PDT
Then, on March 15, Mazar says she woke up with the same symptoms. Her doctor initially refused to test for coronavirus because she didn't meet the criteria, which have typically included travel to an affected area or contact with someone who has or contact with a confirmed or presumptive positive case.
"I found this kind of a CRAZY criteria for a NY’er as I had taken the subway, gone to the theater, the grocery store, the pharmacy, hair salon, etc," she wrote. "I was the Mom who was trying to prepare the home and get supplies & bleach wipes, dry goods. extra food etc."
A few days later she was able to get tested and Mazar said she got the bad news Saturday.
"One day I feel crappy and the next I’m normal," she said in her Instagram post. "Today my lungs are heavy, but I’m tough. I can breath, and I’m going to heal here, in my own home!"
Mazar's entire family is under a 14-day quarantine.
New York City has become the U.S. epicenter for the virus, accounting for at least half of the state's 12,315 cases and 76 deaths. On Friday, Gov. Andrew Cuomo announced "New York on Pause," a set of strict measures that take effect Sunday at 8 p.m EDT. Under the rules, which are intended to slow the spread of the virus, nonessential businesses are closed, workers are ordered to stay home, most travel is banned and social gatherings are canceled. However, mass transit will stay operational through the weekend and food delivery services will stay open.