FLINT, Mich. (WNEM ) — “There’s noise in my brain all the time, 24 hours a day seven days a week,” Gloria Vettese said.

For some COVID-19 survivors, the symptoms seem to never go away.

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“I can’t breathe. It’s almost like I have to think and try harder to expand my lungs since I had COVID-19,” Sarina Szczepanski said.

Two Michigan mothers, Gloria Vettese and Sarina Szczepanski, still fighting to recover from the COVID-19 virus.

After initially beating the illness, mysterious symptoms slowly crept back into their lives. Vettese said after getting COVID-19 in March, she can only describe her symptoms as a constant buzzing in her brain.

“I’ve had a brain scan, I’ve had a heart scan, had a CT appointment, sinuses,” Vettese said. “I had a doppler of my carotid arteries and they’ve had some minor findings and some of them but none of which explain any of the symptoms.”

Vettese said before COVID-19 she was healthy, in fact, she had just gotten a physical. Szczepanski is a nurse, and before COVID-19, she was active and full of energy.

“Now I need brakes. Now I get tired if I take one dog for a walk, I come home and I rest for a little bit because I’m so tired and I can take the other dog for a walk,” Szczepanski said.

Not only did Szczepanski get COVID-19, but it also turned to pneumonia. Her long-term symptoms don’t stop with fatigue.

“I still have issues with smell. I can taste, it’s not the same but it’s close,” Szczepanski said.

Doctors are now trying to get an explanation of what they are calling, COVID-19 long haulers.

People that have symptoms long after getting infected.

“It’s unclear to us there’s a lot we still don’t know about this virus,” Dr. Vineet Chopra said.

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Dr. Chopra is the Chief of Hospital medicine at The University of Michigan. He and other doctors did a study in which they looked at 1600 patients who had been discharged from hospitals across Michigan.

Researchers called them 60 days after they left, and one out of three still had persistent symptoms.

“Anything from persistent cough, difficulty breathing, having trouble climbing up the stairs, all the way up to new problems…. like with their heart, with their circulation,” Chopra said.

Chopra said there is still so much doctors just don’t know about how or why COVID-19 impacts certain people the way it does.

“It was really surprising to just see how many people, either A haven’t recovered, or B had same or worsening symptoms or c had a newer problem they were dealing with even two months after they were out of the hospital from having COVID-19,” Chopra said.

Chorpra said if you’ve already had a pre-existing condition and a weakened immune system, you could experience longer lasting symptoms but for others, it’s a different scenario.

“It’s almost the opposite. It’s like their immune system almost over corrects, so rather than fighting off the infection, it actually starts a fight with their own body, so it continues to fight the lungs, it continues to attack their circulatory system and continue to have these persistent symptoms,” Chopra said.

Vettese is grateful her symptoms weren’t worse, despite the constant ringing in her head.

“I feel lucky for all the testing I have had after, and my symptoms I carry on that I don’t seem to have anything life-threatening. or damage that is that bad,” Vettese said.

Szczepanski too is grateful but fears the future.

“Losing a little taste and smell I can live with but what is it going to do next time? Am I going to be someone who needs to walk around with oxygen?” Szczepanski said.

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