Thomas Eric Duncan, the Liberian man who was the first person diagnosed with Ebola in the United States, died early Wednesday morning. He was 42.

U.S. Ebola Patient Thomas Eric Duncan Dies

Duncan’s death comes after news surfaced that his condition had improved. Four days ago, it was revealed that his condition at the Dallas, Texas hospital had been downgraded from serious to critical. Texas Health Presbyterian Hospital Dallas announced Duncan’s death in a statement.

"It is with profound sadness and heartfelt disappointment that we must inform you of the death of Thomas Eric Duncan this morning at 7:51 am," a hospital spokesperson said. "Mr. Duncan succumbed to an insidious disease, Ebola. He fought courageously in this battle. Our professionals, the doctors and nurses in the unit, as well as the entire Texas Health Presbyterian Hospital Dallas community, are also grieving his passing. We have offered the family our support and condolences at this difficult time."

Duncan had been in Texas visiting family members after spending time in Ebola-ridden Liberia when sickness led him to visit the hospital’s emergency room on Sept. 25. The hospital did not test him for Ebola, instead sending him home with antibiotics. Days later, with worsening symptoms, Duncan arrived back at the hospital via ambulance. He soon tested positive for Ebola and finally received experimental drug Brincidofovir on Saturday.

On Monday, Duncan’s family visited with him and noticed his worsening condition. "What we saw was very painful,” said Duncan’s nephew Josephus Weeks. “It didn't look good.”

By Tuesday, Duncan’s condition had further deteriorated and he was placed on a ventilator and was receiving dialysis.

The total cases of Ebola worldwide is currently at 7,492, while the official death toll is at 3,439.