The Centers for Disease Control and Prevention says recent studies show that about one-third of patients who had COVID-19 become so-called “long-haulers” who suffer from debilitating aftereffects of the virus.

They can include brain fog, fatigue, joint aches, rapid heart rate when standing still and gastrointestinal complaints.

At the New England Institute for Neurology and Headache in Stamford, Dr. Peter McAllister estimates he has 40 to 50 patients who are long-haulers. He says the term has been renamed as “PASC” by the CDC, standing for “post-acute sequelae of COVID.”

Dr. McAllister told News 12 that he's seen kids as young as 10 and adults into their 60s experience the symptoms.

The severity of the symptoms varies, but even people who had mild cases of COVID-19 can later find themselves experiencing them, such as Jim McDonald, of Fairfield. He’s had symptoms for nearly nine months.

“It's real…I was in denial for a while, thought I could power through it,” he says. “So what would happen is I would exert myself, just moderately, and I'd be out for a day maybe two.”

These days, McDonald says he can only walk his dogs for 10-15 minutes. When it comes to work, 3-5 hours is a victory with his debilitating brain fog.

“The best I can describe it is like when you have a concussion and you can’t remember who you are – and it comes at weird times,” he says.

Dr. McAllister says there still isn’t a “complete picture” on how to treat the issue, but says the COVID-19 vaccine could be a way out.

“There's a little bit of evidence, and it's encouraging, that if someone with long haul were to get the COVID vaccine, at least a third of those people, seem to have a drop or even a complete elimination of their symptoms,” he says.

That's what McDonald is hoping for. His second shot is coming in the next few weeks.

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