Even people who only get mildly sick from COVID-19 can experience symptoms for months. It is called long COVID with patients reporting side effects and symptoms long after they are free of the virus.

Researchers collected a list of symptoms associated with long COVID, and it’s long. There are 55 in all.

So, what exactly is long COVID?

Because the virus is new, the research is happening in real time.

Who’s affected? So far, the research shows one in three adults who had COVID-19 also experience long COVID. Children have it too.

The why is less understood.

Straight Arrow News medical expert Dr. Payal Kohli said there are three theories behind long COVID.

“One theory is you have persistent viral fragments that are present, that are creating inflammation or immune response in the body,” she said. “The other theory is the inflammation that’s already been activated is sort of lingering and continuing to cause problems. And then the third theory is that the virus or the inflammation created damage to cells, tissues, or organs that is continuing to cause long COVID.”

Long COVID could be persistent symptoms or side-effects, or it could be re-occurring bouts. Everyone’s different.

The study published in Nature’s Scientific Reports in August reviewed thousands of other studies of long COVID effects.

It included 47,910 patients in all, ranging from 17-87 years old.

There were 25 symptoms identified as most common with fatigue coming in first by affecting 58 percent of people.

Headaches came in second at 44 percent, and attention disorder, which many call brain fog, came in at 27 percent.

Other common symptoms topping the list are ones we’ve heard about all along like difficulty breathing, loss of taste or smell and coughing.

The 25 most common symptoms according to the study:

• Fatigue (58%)
• Headaches (44%)
• Attention disorder (27%)
• Hair loss (25%)
• Dyspnea, or difficulty breathing (24%)
• Ageusia, or loss of taste (23%)
• Anosmia, or loss of smell (21%)
• Post-activity polypnea, or heavy breathing/panting/sweating (21%)
• Joint pain (19%)
• Cough (19%)
• Sweat (17%)
• Nausea or vomiting (16%)
• Chest pain (16%)
• Memory loss (16%)
• Hearing loss or ringing in the ears (15%)
• Anxiety (13%)
• Depression (12%)
• Digestive disorders (12%)
• Weight loss (12%)
• Cutaneous signs, or skin and dermatological issues (12%)
• Increase in resting heart rate (11%)
• Palpitations (11%)
• Pain (11%)
• Intermittent fever (11%)
• Sleep disorder (11%)

Dr. Kohli said many of these most common symptoms are treatable.

“A lot of people with long COVID are having a lot of success doing physical therapy, respiratory therapy, cardiopulmonary rehabilitation,” she said. “All those types of things [help] get their exercise tolerance back.”

The other 30 long COVID symptoms are labeled less common and range from psychiatric disorders to kidney failure. See the full list from the study here.

So, what can be done to stop or prevent long COVID?

Dr. Kohli said the best way to protect against long COVID is to get vaccinated.

“There’s actually encouraging data that number one, time heals,” she said. “But the other anecdotal and encouraging evidence that’s emerged is that getting a shot of the vaccine if you haven’t already been vaccinated, if you had COVID and hadn’t received the vaccination when you had it can actually help to sort of reset your immune system. And can really help resolve some of that persistent inflammation or viral fragment or whatever it is that is causing the long COVID. So, a lot of people who have had long COVID have experienced relief after getting vaccinated from their long COVID symptoms.”

The study also found long COVID lasts from two weeks to three and a half months.

But some people who had COVID-19 at the beginning of the pandemic, are still battling fatigue and brain fog.

Because the virus is so new, doctors don’t know how long the symptoms will last or if they will ever go away.