(CNN) Five people who recently evacuated Wuhan, China, to Travis Air Force Base in Northern California were hospitalized Friday with symptoms of coronavirus , according to a US Centers for Disease Control and Prevention spokesman.

It was determined that the five people had a fever and were taken by ambulance to an undisclosed nearby hospital where they are being isolated and tested for the virus, CDC spokesman Jason McDonald told CNN.

Four of the five patients arrived this morning on a flight at the base. An additional person arrived on Wednesday and was hospitalized after showing symptoms, according to the spokesman. Most of the evacuees who arrived at Travis AFB on Friday morning continued on to San Antonio, Texas, but 53 people remained at the Northern California base.

The evacuees are part of the close to 300 additional Americans arriving in the US Friday on two flights after evacuating the epicenter of the coronavirus outbreak in China.

One flight landed early Friday at Travis Air Force Base -- between San Francisco and Sacramento, California -- a base official told CNN. The second US-bound flight landed first at Vancouver International Airport, facility management spokesman Brock Penner said.

The flights' final destinations are Eppley Airfield in Omaha, Nebraska, and the Marine Corps Air Station Miramar in San Diego, the Defense Department's US Northern Command said.

Everyone on the flights will be subject to a 14-day federally mandated quarantine.

A group of Colby College students returning to Maine from a trip to China are under "self-quarantine" at a hotel in Waterville, Maine, at the request of the school, even though there are no confirmed cases of coronavirus in Maine, according to the state's Centers for Disease Control.

The fast-moving coronavirus emerged in the central Chinese city of Wuhan two months ago. Since then, it has killed 724 people, mostly in China where it has trapped residents at home and paralyzed the world's second biggest economy

Outside mainland China, it has raced across continents, infecting over 34,000 in more than 25 countries and territories. In the US, there are at least 12 confirmed cases

Here are other key developments this week:

The outbreak just keeps growing

This week saw the number of cases reported in the outbreak more than double worldwide.

At the end of last week, there had been 14,549 confirmed cases of coronavirus and 305 deaths worldwide. The US had eight cases.

Japanese officials updated the number of coronavirus cases aboard the Princess Cruises ship -- called the Diamond Princess -- which authorities quarantined to prevent the spread of the virus. As of Friday night, there were 64 confirmed cases of the coronavirus on the Diamond Princess, 13 of whom are American citizens.

Other countries have started evacuating citizens from China as well.

About 150 British citizens will be flown from Wuhan back to England Sunday, the UK's South Central Ambulance Service said on Friday. Those patients will be transferred to a facility in Milton Keynes, north-west of London, where they will be quarantined for 14 days.

Two Brazilian Air Force planes also left Wuhan Friday, according to the Brazilian Air Force's official Twitter account. Aboard the plane were 34 Brazilians, four Polish citizens, one Chinese citizen and an Indian citizen. The non-Brazilian citizens will be dropped off during the flight's layover in Poland. Once in Brazil, the citizens will be quarantined for 18 days on an Air Force base.

In Canada, a flight carrying 176 passengers landed late Thursday at Vancouver International Airport, an airport official there said.

US likely not chartering any more flights out of Wuhan

As the numbers skyrocket, the US has worked to get Americans out of China.

The flights that arrived Friday in the US from Wuhan could be the final two flights chartered by the State Department.

The State Department does not anticipate chartering any planes after this week, an official said.

All the passengers will be quarantined

The health of passengers headed to the US will be monitored and checked repeatedly during their flights. After disembarking, they will be screened and placed under a 14-day federally mandated quarantine, according to the US Northern Command, a part of the Department of Defense.

Those who show symptoms upon arrival or during the quarantine period will be taken to area hospitals for isolation and treatment.

Evacuations of Americans from Wuhan started last month, with one flight carrying nearly 200 Americans landing at the March Air Reserve Base in Southern California. Those passengers were quarantined.

On Wednesday, two more flights out of Wuhan arrived in California, carrying a total of 350 passengers. They were taken to Travis Air Force Base and the Marine Corps Air Station Miramar. They were also quarantined.

The 65 passengers who arrived on Friday at Miramar Friday received health screenings and remain on the base with the other evacuees who arrived Wednesday.

A total of seven people from MCAS Miramar were transported to the hospital after developing a fever or a cough that warranted further evaluation.

Quarantine covers those on regular flights from China

The federal quarantine order applies to Americans arriving on regular passenger flights, as well.

US citizens returning from China on commercial flights are being rerouted to one of 11 airports that can handle extra health screenings. Those passengers may be subject to quarantine, according to new federal rules that went into effect February 2.

The 11 designated commercial airports are in: New York (John F. Kennedy), Los Angeles, Seattle, San Francisco, Chicago (O'Hare), Atlanta, Honolulu, Dallas, Detroit, Newark and Washington (Dulles).

The Pentagon announced that 11 additional military locations have been approved to accept people for quarantine if public health authorities believe there are coronavirus concerns. The additional military housing sites are located near the 11 airports accepting flights.

The outbreak is not just on land

Passengers are not just trapped at home and in military bases.

More than 7,300 people are being quarantined on two cruise ships docked in Hong Kong and Japan over concerns they were inadvertently exposed to the coronavirus by infected passengers.

At least 64 people from all over the world have tested positive for coronavirus on the cruise ship docked in Japan, including 11 Americans.