Patrick Sawyer had one stop to make before heading home to Minnesota to celebrate his daughters' birthdays: a conference in Lagos, Nigeria.

But when he landed in Lagos, Sawyer, 40, collapsed getting off the plane. He had been infected with Ebola in Liberia, where he worked as a top government official in the Liberian Ministry of Finance.

Sawyer was isolated at a local Nigerian hospital on July 20. He died five days later.

Sawyer's wife Decontee Sawyer, lives in Coon Rapids, Minnesota, with the couple's three young daughters, 5-year-old Eva, 4-year-old Mia, and Bella, who is 1. The Sawyers are naturalized citizens; their daughters were born in the United States.

"He was so proud when he became a U.S. citizen," Decontee told CNN. "He voted for first time in the last U.S. presidential election. He lived in the U.S. for many years, and wanted that for Liberia - a better democracy."

Sawyer had been caring for his Ebola-stricken sister in Liberia, Decontee said, though at the time he didn't know she had Ebola.

Sawyer is the first American to die in what health officials are calling the "deadliest Ebola outbreak in history." His death has sparked concerns that the virus could potentially spread to the United States.

"People weren't really taking it [Ebola] seriously until it hit Patrick," Decontee said. "People are ready to take action."

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