What is COVID-19 pneumonia?

HOUSTON, Texas (KTRK) -- COVID-19 pneumonia is often referred to as "severe" COVID, but what is it? Who is at risk of getting it?

ABC13 asked Dr. Rodrigo Hasbun, a professor of medicine in infectious diseases at UTHealth, about the illness.

What is COVID pneumonia?

"When you have a viral infection and it first sets in, in a sub group of patients, about 10% to 15% of the patients, you'll develop a very large immune reaction to the virus, and that is what develops and causes the pneumonia," Hasbun said.

Who falls into that 10% to 15%?

"The risk factors for getting pneumonia are diabetes, the patients are immunosuppressed, the obese," explained Hasbun. "A lot of obese patients get COVID pneumonia. Those are the patients at high risk of getting COVID pneumonia. Other patients can develop pneumonia as well, but they are more at risk at developing this complication."

What symptoms would suggest your infection has progressed to pneumonia?

"If your oxygen level starts dropping and you become short of breath, those are very important symptoms that suggest you may have developed pneumonia and may need to go to the hospital," Hasbun said.

How severe is it?

"COVID pneumonia is really the start," Hasbun said. "They develop acute respiratory distress syndrome (ARDS), and then they get intubated and ventilated and those are the patients who usually die from COVID. With the new medications, we are seeing less of a mortality when we didn't have all these medications."

Do patients with COVID pneumonia face more severe complications with their case?

"Patients with COVID pneumonia are the ones who are going to develop more complications due to COVID," Hasbun said. "We see, not only hematological complications, like clots or pulmonary embolism with COVID pneumonia, but also neurological abnormalities or even strokes with COVID pneumonia."

Is COVID pneumonia new?

"No, it's been going on since last year," he explained. "When you talked about severe COVID patients who are intubated, that was COVID pneumonia in 2020."

Is it treatable?

"We have treatments for COVID pneumonia," Hasbun said. "We give patients steroids. They get antivirals, like Remdesivir to try to ameliorate that immune reaction to the virus so you can improve the patients' outcomes."

What is the outlook for someone who gets it?

"Last year, we didn't have all those medications, so we were just basically seeing them progress and not doing anything to prevent the progression at the beginning of the pandemic," Hasbun said. "We saw how they progressed overnight and they got intubated. Once they are intubated, it is very difficult. Some make it out. Some end up having a lung transplant, because their lungs are damaged with pulmonary fibrosis and some die."

Does the vaccine prevent it?

"We've seen patients who are fully vaccinated getting COVID pneumonia," Hasbun said. "Typically, those are immunosuppressed, so if you have a loved one who is immunosuppressed and you're home, everyone should be vaccinated."

How can someone monitor if their illness is progressing at home?

"If you have COVID, you can buy a pulse oximeter online. They are very inexpensive and they can monitor your oxygen saturation," Hasbun said. "If you start developing shortness of breath and you see your oxygen saturation is dropping, that is basically telling you, 'You have pneumonia and you need to go to the hospital.' Normal oxygen saturation should be 97%, 98%, 99%, 100%."

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