In yet another twist on mysterious COVID-19 symptoms, some patients suffering from the virus might end up with “happy hypoxia.”
Also known as silent hypoxia — meaning, a lack of oxygen in the body’s tissues — the condition occurs when oxygen levels plummet extremely low, yet the patient is still talking and often even walking. This is why it’s considered “silent” or “happy” because the person is unaware of what’s going on.
By the time these people decide to go to the hospital, they’re in bad shape and don’t even realize it.
They Shouldn’t Even Be Upright

Dr. Richard Levitan, an ER physician who recently volunteered in a New York City emergency room, told CNN that his patients were arriving in dire need of oxygen. While normal blood oxygen levels are between 100%- 95%, anything under 90% is considered a problem.
Some of Levitan’s patients had levels as low as 50%, and they often had severe pneumonia. Yet, they weren’t in extreme discomfort. Doctors surmise that this is because the body adjusts to a faster breathing rate over time, and becomes accustomed to lower oxygen levels — as happens when traveling to high altitudes. This silent hypoxia often leads to respiratory failure and even death; even being intubated and put on a ventilator doesn’t always have great outcomes.
“It’s intriguing to see so many people coming in, quite how hypoxic they are,” Dr. Jonathan Bannard-Smith, a consultant in critical care and anesthesia at Manchester Royal Infirmary, told The Guardian. “We’re seeing oxygen saturations that are very low and they’re unaware of that. We wouldn’t usually see this phenomenon in influenza or community-acquired pneumonia. It’s very much more profound and an example of very abnormal physiology going on before our eyes.”
One Man’s Story of Happy Hypoxia

(Photo: Morgan Smith)
Morgan Smith is a healthy 53-year-old living in Colorado. He’s pretty sure his entire family of four ended up with COVID-19 after they started their quarantine; they suspect his son may have been infected at college before returning home. While Smith’s family members had mild cases (fatigue and fevers, mostly), Smith ended up in the hospital. And he was lucky.
It took 15 days from his initial exposure for “all hell to break loose,” Smith wrote of his ordeal on Facebook.
“About midnight, (my wife) woke me up saying that I was rapidly breathing and sounded bad and I should go to the hospital. We took my temperature and it had shot up to 103. Being exhausted, I did not want to and wanted to go back to sleep but she made me because I did not look good. As I tried to get ready, I noticed I had lost coordination and balance and could barely get dressed and just moving was causing difficulty breathing.”
When Smith arrived at the hospital, his blood oxygen level was 74%. Remember: normal is between 95-100%. He was fortunate to still be conscious.
“I was given oxygen and that was able to get my levels back to normal as long as I had a continuous supply,” Smith wrote.
His x-rays indicated classic COVID-19 pattern pneumonia in both lungs. He was very fortunate to respond to the oxygen and supplemental antibiotics. (While those don’t treat viral pneumonia, they sometimes help the body with secondary infections.) Smith didn’t need a ventilator, was in the hospital for three days and came home with an oxygen tank.
“I guess the key takeaway point of all this is to watch out for this virus,” he said. “It is sneaky, hard to detect, and hard to tell the difference between a mild case, which can be little or nothing and the unlucky 20%. The reason we have all upended our lives and we are taking all these precautions makes a whole lot more sense when you realize what this thing can do if it’s allowed to infect everyone without limitation at the same time.”
Watch for Signs

Because of the virus’s “sneaky” cumulative qualities, if you think you have COVID-19, stay vigilant.
Dr. Stacey Ludwig in Los Angeles has seen happy hypoxia in action. “As an urgent care physician working on the front line, I have seen multiple COVID-19 patients coming in with low or borderline oxygen saturation levels,” she tells Parentology. “Most of them do feel some level of chest tightness or shortness of breath that is worsened with activity.”
Self-isolation when sick is a must, but Ludwig says there’s a time to make a break for the ER.
“While it is recommended for people with mild cases to self-quarantine at home, if someone with COVID-19 begins to feel winded or has severe fatigue when walking room to room in their home, or if they are having trouble speaking in whole sentences due to feeling short of breath, they need to be evaluated at their closest urgent care or emergency room as soon as possible,” Ludwig advised.
Getting help in time also means avoiding ventilators and their less-than-appealing outcomes. Levitan recently co-authored a paper on an alternative, far less invasive treatment: Doctors offered 50 patients supplemental oxygen instead of ventilators and positioned them on their sides and tummy, positions often used to help open the lower lungs. While 13 of the patients still needed to be intubated, it helped the remainder of the small sample.
“We found two out of three patients can avoid a ventilator during the first 24 hours by putting them on oxygen and doing these positioning maneuvers, such as laying them prone on their stomach,” he told The Guardian.
Happy Hypoxia COVID-19 — Sources
Dr. Stacey Ludwig, Los Angeles
CNN
The Guardian
ScienceMag