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5 Signs You've Already Had COVID, According to an Expert

Post-COVID Syndrome can resemble Chronic Fatigue Syndrome, says this doctor, who adds it can be treated.

How do you know if you've already had coronavirus? As a doctor, I am asked this often. Although there are numerous symptoms of COVID, many of these, such as fever, can occur from numerous infections. Plus, an estimated 40-45% of patients are asymptomatic and may not feel anything. But if you had a severe, dry cough and shortness of breath, these are most suggestive of coronavirus. Cough and shortness of breath occur because of the virus infecting the lungs. Of course, the best way to know for sure if to get tested and quarantine until you have the result, but other signs you've already had coronavirus—or have Post-COVID Syndrome, which can last for months after infection—include the following. Read on, and to ensure your health and the health of others, don't miss these 35 Places You're Most Likely to Catch COVID.



Depressed woman awake in the night, she is touching her forehead and suffering from insomnia

You'll feel this as your body diverts energy production to fighting the infection.



Young man suffering from cold at his home

A fever occurs as the body tries to make the local temperature inhospitable to the virus.

RELATED: COVID Symptoms Usually Appear in This Order, Study Finds


"Brain Fog"

depressed Indian woman holding head in hands, sitting alone on couch at home

Dr. Anthony Fauci has called this "difficulty in concentrating" or a sudden "confusion."  It is common with numerous infections as your body produces interferon and because of toxins from the infections (and numerous other causes). 


Sore Throat

woman touching her neck and feeling pain in throat while sitting in the living room at home.

You might experience this because of the virus infecting the throat.


Nausea and Diarrhea

Middle aged woman suffering from abdominal pain while sitting on bed at home

The virus can also infect the stomach and intestines.

RELATED: Dr. Fauci Says Most People Did This Before Catching COVID


You Might Have Post-COVID Syndrome 

trouble sleeping

Post-COVID Syndrome is when you have persistent symptoms of fatigue, insomnia, brain fog, cough, and shortness of breath more than three weeks after the infection. Other symptoms can also be present, but these are the most important. (Specific injury to the lungs, brain, and heart also contributes to symptoms.) Dr. Fauci has correctly noted that this represents post-viral chronic fatigue syndrome. This is when a severe energy crisis causes people to trip an almond sized circuit breaker in the brain called the hypothalamus. This results in inability to sleep, widespread hormonal deficiencies, brain fog, fatigue, and your brain not getting enough blood when you stand. 


Is There a Cure for Post-Viral Syndrome?

Doctor wearing protection mask against covid taking notes during consultation with patient in medical clinic

I had post-viral chronic fatigue syndrome in 1975. It knocked me out of medical school and left me homeless for a year. Once I learned how to recover, I spent the next 45 years researching and developing effective treatment for post-viral chronic fatigue syndrome. 

Numerous studies are underway trying to understand the causes of post-COVID syndrome. But the good news is that post-viral chronic fatigue syndrome, and persistent post-COVID symptoms, are very treatable. Our published placebo-controlled study showed that SHINE (optimizing Sleep, Hormones, Immunity, Nutrition, and Exercise as able) resulted in an average 90% increase in quality of life, making this very treatable. I feel post-COVID can be effectively treated and now. The problem is not lack of effective treatments, but rather lack of effective physician education. Discuss Post-COVID Syndrome with your doctor—or a post-viral specialist like me—and to get through this pandemic at your healthiest, don't miss the comprehensive list of the Sure Signs You've Already Had Coronavirus.

Jacob Teitelbaum, MD
Jacob Teitelbaum, M.D., is one of the most frequently quoted chronic fatigue syndrome and fibromyalgia medical authorities in the world. Read more about Jacob