His friends say it happened in a matter of days.
Danny Plata, 38, of Bonita, was put on a ventilator Saturday, but his condition quickly worsened and now he's fighting for his life.
A single dad to two kids, Plata is loved by his family, co-workers and patients at Sharp Chula Vista.
"He's just someone you can depend on, especially working side by side when you know there is a pandemic and a global crisis. He is one of those persons you want by your side," said Fabiola De La Torre, a coworker of Plata's in the Emergency Department at Sharp.
"He is one of the nurses that as soon as someone comes in that is critically ill in the ambulance, he runs towards it, you know, he puts himself at risk," she said of Plata's dedication to his work and patients.
De La Torre said they don't know where Plata contracted COVID-19, but he was also caring for his own father who tested positive for the disease.
On Saturday, Plata was put on a ventilator. By Tuesday, he underwent ECMO, a process where the blood is pumped outside his body to receive oxygen, giving his heart and lungs a break and the opportunity to heal.
"This is his last resort, ECMO is his last possibility or intervention," De La Torre told NBC 7. "Right now that he is unconscious and in a coma. We are all trying to help out."
Sharp nurses set up a GoFundMe page to help pay for Plata's medical expenses and to provide for his kids. They are asking the community to come together to take care of a man who has always taken care of everyone else.
If you'd like to donate to the GoFundMe, click here.