(Updated: 2:21 p.m. ET) -- Tonga is the latest country to ban international cruise ships due to fears surrounding the coronavirus, after entry to Nuku'alofa was denied today to Crystal Cruises' Crystal Serenity, CMV's Columbus and Transocean Kreuzfahrten's Astor.

Crystal Serenity will instead dock at Lautoka, Fiji, tomorrow; Columbus will sail directly to Suva, Fiji, and extend its overnight stay; and Astor will proceed to Auckland, New Zealand.

The move follows decisions by other South Pacific ports, Hong Kong, Japan, Taiwan, South Korea and Kota Kinabalu, Malaysia, to close their ports. A number of Caribbean ports also turned away German cruise ship AIDAperla because some passengers were showing signs of the coronavirus.

Holland America Line's Westerdam has been denied entry to the Philippines, Japan, Taiwan, South Korea, Guam and Thailand.

The ship had been scheduled to call at Ishigaki Island, Naha, Okinawa, Nagasaki and Fukuoka (Hakata) -- despite the vessel not being in quarantine and there being no known cases of coronavirus onboard. It is scheduled return Feb. 15 to Yokohama, where the next cruise was scheduled to embark, but it is not clear where it will dock now.

HAL released the following statement: "We are quickly working to develop alternate plans and are keeping guests updated on board as information becomes available. The next cruise that was scheduled to embark in Yokohama on Feb. 15 has been canceled. Booked guests and their travel advisors will be notified."

Meanwhile, in Yokohama, Princess Cruises' Diamond Princess is quarantined, with more than 130 passengers testing positive for the virus.

And in Hong Kong, more than 1,800 passengers and 1,800 crew were in lockdown on Dream Cruises’ World Dream in Victoria Harbour while waiting for test results from 30 people who have reported symptoms of coronavirus. The ship has been temporarily taken out of service.

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