Navy officials say they've been unable to make a definitive link between hundreds of coronavirus cases on an aircraft carrier and a controversial port call in Vietnam, leading them to consider the possibility that pilots delivering goods to the ship carried it aboard.
Carrier onboard deliveries, known as CODs, could be to blame for the ongoing health crisis onboard the carrier Theodore Roosevelt, a Navy official told Military.com. The flights in question could have originated in the Philippines or Japan as the carrier operated in the Asia-Pacific region, the official said.
When the first coronavirus cases among the crew were announced late last month, questions were raised about the decision to have the ship make a planned stop in Vietnam in early March. But the sailors got sick with COVID-19, the illness caused by the coronavirus, 15 days after it left the country, the official said.
The incubation period for COVID-19 is believed to span between two and 14 days.
"It's not conclusive, and it's very hard to tell if we're going to be able to get to a conclusive, 'This is where it came from,'" the Navy official said. The Wall Street Journal first reported that the Navy was considering CODs as a possible explanation behind the outbreak.
CODs bring mail, replacement parts and other supplies out to carriers from ashore almost daily. The Navy uses C2A Greyhound twin-engine cargo planes and CMV-22B Osprey tiltrotor aircraft for the mission.
The aircraft typically board the carriers at the start of a deployment, but leave once land is in range. There, they set up at the nearest large airport and commence shuttle runs, the Smithsonian's Air and Space magazine described in a feature on their missions.
The Navy has faced criticism over the decision to have the Roosevelt stop in Vietnam in early March as coronavirus cases spread throughout the region. President Donald Trump was one who questioned the decision, blaming the ship's former commanding officer, Capt. Brett Crozier.
"Perhaps you don't do that in the middle of a pandemic or something that looked like it was going to be," Trump said. "History says you don't necessarily stop and let your sailors get off."
But the call was made by two admirals in coordination with several other government agencies. Adm. John Aquilino, head of Pacific fleet, recommended the port visit occur as scheduled, and Adm. Phil Davidson, head of U.S. Indo-Pacific Command, approved it, said Cmdr. J. Myers Vasquez, a Pacific Fleet spokesman.
"This decision was made after a thorough assessment in coordination with Department of State, Office of the Secretary of Defense, U.S. Indo-Pacific Command, U.S. Pacific Fleet, the Vietnamese Ministry of Foreign Affairs and Ministry of Defense, U.S. Embassy in Vietnam, and associated health experts," he added.
Chief of Naval Operations Adm. Michael Gilday has called the decision "a risk-informed" one and said there were just 16 COVID-19 cases in Vietnam at the time, and they were isolated in Hanoi.
The guided-missile cruiser Bunker Hill, which stopped in Vietnam with the Roosevelt, hasn't reported any COVID-19 cases, Defense Secretary Mark Esper said this week.
Vasquez said the crews got a brief from medical personnel on coronavirus prevention. And when two British people tested positive for the illness at a hotel that dozens of sailors had visited, those personnel were tested for COVID-19 and placed into quarantine for 14 days, he said.
None of those personnel were among the first three Roosevelt crew members to test positive for COVID-19, Vasquez added.
Both ships left Vietnam on March 9. The first three Roosevelt sailors to have flu-like symptoms and test positive for COVID-19 did so on March 24 -- 15 days after they left, Vasquez said.
"Theodore Roosevelt medical representatives conducted a thorough contact tracing to determine who these individuals came in contact with in an attempt to identify the origin of the infection," he added. "Since 14 days had passed, ship's medical was unable to determine the specific source."
Other carriers have adjusted their flight operations to prevent pilots and crews from infecting any sailors onboard, Rear Adm. Andrew Loiselle, commander of Carrier Strike Group 8, told reporters this week.
The Harry S. Truman Carrier Strike Group left the Middle East and was scheduled to head back to the East Coast. Now it'll continue operating at sea.
The crew is COVID-19-free, and the Navy needs to have a healthy strike group at the ready, as the Roosevelt has been sidelined in Guam for nearly a month now.
Deliveries bound for the strike group spend enough time aboard supply ships that any possible infected residue dies off before it's delivered, Loiselle said. And if helicopters or planes that take the supplies onto the Truman, those inside aren't allowed to step foot onto the ship.
"We gave them a box lunch and sent them on their way," Loiselle said.