Frank Eller's COVID-19 survival story is giving the world hope. 

The 87 year old retired Marine from San Diego was in critical condition after being diagnosed with the virus just weeks ago while on a cruise ship. 

"I was very weak. I couldn't stand or walk very far. At night, I couldn't breath laying down," said Eller.

He was evacuated from the ship on March 9, and airlifted to a hospital in Puerto Rico where had to stay for two weeks. 

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"Gradually from that first day, I began to feel better. I felt by the sixth day I was fully recovered and ready to go," Heller added.

He arrived with pneumonia and five underlying health conditions: emphysema in one lung, heart disease, leaky heart valve, peripheral nephropathy, and an irregular heartbeat. 

Eller said he refused to be put on a ventilator.

He attributes his resilience to his family, faith, and his years of service with the Marine Corps.

He survived the war back then, and the war against a virus now.

"Ooh-rah," he shouted with joy.