A Phoenix Air jet carrying Dr. Martin Salia lands in Omaha, Neb., on Nov. 15. He died from Ebola at Nebraska Medical Center two days later. (Nati Harnik/AP)

There has been an apparent first in the fight against Ebola this week.

According to flight records, the private jet company contracted by the State Department to transport Ebola patients flew two air ambulances to West Africa on the same day.

Until Wednesday, Phoenix Air had flown only one Ebola-fighting mission at a time. A second Gulfstream jet featuring the ability to treat infectious patients in flight had been held back in case of an emergency with the first aircraft. But last month, the Georgia-based operation finished customizing a third jet to handle the specialized medical equipment.

A tentlike structure allows caregivers to treat a single Ebola patient in flight without infectious germs escaping. (CDC via Reuters)

The increased rescue capacity comes just in time. On Thursday, the Red Cross warned of a possible rise in the rate of Ebola infections in West Africa as people travel across the region during the holidays.

One of this week’s flights brought an American nurse to the Washington area. On Thursday, the National Institutes of Health announced that an unidentified relief worker who was exposed to the Ebola virus while volunteering in Sierra Leone was being admitted.

So far, no information is known about the mission of this week’s second Ebola flight. Messages left for Phoenix Air were not immediately returned on Thursday. A State Department spokeswoman said she could not immediately answer questions from Yahoo News.

“We won’t have anything for you on this today and may not have something until early next week,” the spokeswoman said via email.

[Related: US was ill-equipped to handle Ebola rescues, State Dept. contract reveals]

There appears to be no public flight plan mapping either jet’s departure from Léopold Sédar Senghor International Airport in Dakar, Senegal. Yahoo News asked a Phoenix Air official last month about a noticeable increase in keeping flight information off of databases searchable by the public.

“The only thing I can say is that it's for operational security,” said Dent Thompson, the company’s vice president of operations. “There are a whole lot of things going on in the background, and whatever we do, it is in cooperation with the government and us.”

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Of the flight plans that are public, records show Phoenix Air has made at least five trips to West Africa this month.

One of those was Dec. 4, to bring an American health care worker who may have been exposed to the Ebola virus to Atlanta’s Emory University Hospital.

On Thursday, an Emory spokesperson declined to say if the patient had tested positive for the deadly disease, but did confirm that the woman is still being treated in the hospital’s serious communicable diseases unit.

An expedited multimillion dollar agreement with the State Department in August put Phoenix Air on retainer through mid-January to transport Ebola-stricken patients at U.S. request. Both parties told Yahoo News last month that an extension was in the works. It’s unknown if a new deal has been reached. The State Department spokeswoman said she could not provide details on Phoenix Air’s expiring contract.

At least six Phoenix Air Ebola evacuees from West Africa have not been brought to the United States. Because of the specialized equipment and complicated missions, the State Department has allowed foreign governments and aid organizations to piggyback on its deal with Phoenix Air if they agree to cover the costs.

(Editor's note: This story was updated at 6 p.m. ET.)

Jason Sickles is a reporter for Yahoo. Follow him on Twitter (@jasonsickles).