Ramona Singer says she felt COVID-19-related symptoms in February, but was never tested for the virus

Ramona Singer is revealing new information about her health amid the coronavirus pandemic.

The Real Housewives of New York City star and her daughter Avery both tested positive for COVID-19 antibodies.

"We both found out we have the antibodies, so we donated our plasma," Ramona tells PEOPLE exclusively.

Looking back, the Bravo star, 63, says she felt mild symptoms in February, but due to lack of information and testing availability at the time — and her coinciding Lyme disease diagnose — she was never tested for the virus.

"I had no energy," she recalls. "I just wanted to stay in bed all day. I felt very tired, and I also had severe headaches."

Testing positive for COVID-19 antibodies indicates that a person has been exposed to the virus. However, the Centers for Disease Control has warned that the currently available antibody tests may not be accurate, and should not be used to determine if someone is immune to COVID-19.

Ramona Singer and Avery Singer
Credit: Jamie McCarthy/amfAR/Getty

In early March, both Ramona and her daughter joined her ex-husband Mario Singer in Boca Raton, Florida, to self-isolate together as a family. But when Avery, 24, arrived in the Sunshine State, she began feeling under the weather.

"She just thought maybe she had a cold or a sinus infection, because she wasn't able to taste food and she lost her sense of smell," says Ramona. "We kept her quarantined in a separate part of the home because, not realizing I had already been sick, I was afraid my Lyme disease had weakened my immune system and I would be more vulnerable to catching an illness."

In May, Ramona, Mario and Avery decided to get tested for coronavirus antibodies.

"We all got tested. Avery and I both tested positive, but Mario was negative," she says. "We are all so lucky that we have our health."

"The Real Housewives Of New York City" Season 5 Premiere Viewing Party Hosted By Ramona Singer And Sonya Morgan
Ramona Singer and ex-husband Mario Singer
| Credit: Simon Russell/Getty

Ramona also says her Lyme disease symptoms are gone. She credits maintaining her workout routine and eating clean, and says she stayed in close touch with her doctor.

"I'm so focused on my health," she says. "I have such a strong immune system that my body fought it off. I'm very blessed."

After consulting with her doctor and getting cleared to travel, Ramona and Avery left Florida earlier this month. The reality star says she took every necessary safety precaution while flying before returning to her house in the Hamptons.

"When I was on the plane, I wore a mask the whole time, I wore gloves the whole time, and I was washing down everything," she says. "I was — and continue to be — extremely socially responsible."

And looking back on her quarantine experience, Ramona says spending three months in Florida with her ex and her daughter only brought them closer together as a family.

"It was so special," she says. "The memories that Avery is going to walk away with is just beyond. I made a dinner for our last night together, and she made a toast and she hugged her daddy. She just said this was the best experience. She said, 'Even though this was a bad situation for the country and the world, this was the most positive experience I could ever have.'"

"We made lemonade out of lemons, I have to say," she adds. "We really did."

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