Fears Rise Over Coronavirus as American Cruise Passenger Is Diagnosed After Previously Showing No Symptoms

Fears over the COVID-19 coronavirus spreading to more countries have escalated after an American cruise passenger, who previously showed no symptoms, was diagnosed with the virus on Sunday after disembarking the MS Westerdam, a cruise ship from the Holland America Line (a subsidiary of Carnival Corporation).

The vessel carried 1,455 passengers (around 600 of whom were reported to be American) and 802 crew members, all of whom had undergone health checks and were cleared for travel after reporting no symptoms of illness. As authorities scramble to track the other passengers who were allowed to disembark the ship in Cambodia, the latest diagnosis has sparked concerns that people showing no symptoms could be slipping through the cracks of the health screening process.

The deadly virus, which was first identified in Wuhan in the Hubei province of China, has claimed the lives of at least 1,669 people, with around 71,000 cases confirmed across 26 countries as of Monday morning, according to the latest report by the World Health Organization (WHO).

The 83-year-old American woman aboard the MS Westerdam flew from Cambodia to Malaysia where she was stopped at Kuala Lumpur International Airport after testing positive for the coronavirus, Malaysian Deputy Prime Minister Wan Azizah Wan Ismail confirmed, The Star reports.

The woman was said to have not visited the ship's medical center to report any symptoms of illness while she was aboard the MS Westerdam and the 20 other guests who did report to the ship's medical center during the cruise journey all tested negative for the virus. The woman is currently at a hospital in Malaysia and is in a stable condition, the Holland America Line confirmed in a statement on Monday.

The 85-year-old husband of the infected woman tested negative for the virus but around 255 other guests and 757 crew members remain on the ship, awaiting clearance for travel while the Cambodian Health Ministry is aboard to test each person for the virus. Passengers at a hotel in Phnom Penh, the capital of Cambodia, are also being screened. The first batch of 406 people have all tested negative, the statement said.

Around 137 of the 145 passengers that were on chartered flights from Cambodia to Malaysia have already left for other countries, after being previously cleared for travel, Malaysian authorities confirmed. Dozens of others have also flown to Thailand and to other countries, according to Thailand officials, Reuters reports.

"At this time [Monday morning], no other guests or crew on board or at the hotel have reported any symptoms of the illness. Guests who have already returned home will be contacted by their local health department and be provided further information," the cruise company said in the statement.

"We are in close coordination with some of the leading health experts from around the world," Dr. Grant Tarling, chief medical officer for Holland America Line, said in the statement.

"These experts are working with the appropriate national health authorities to investigate and follow-up with any individuals who may have come in contact with the guest," he added.

The screening of the remaining passengers aboard the MS Westerdam is expected to take several days, the company states.

"Holland America Line will provide a further update once we have more information," the statement said.

The MS Westerdam has been refused entry to several countries, including Japan, Taiwan, Guam, the Philippines and Thailand, since February 1 after it visited Hong Kong, where it reportedly picked up around 600 new passengers.

Last week, the U.S. State Department raised its travel advisory to Hong Kong to "Exercise Increased Caution" in view of the ongoing coronavirus outbreak and the Hong Kong government also "upgraded its response level to emergency, its highest response level, and is taking other steps to manage the novel Coronavirus outbreak," the State Department noted. The department's travel advisory to China remains at Level 4, the highest level, which states: "Do not travel" to China.

The MS Westerdam was finally able to dock in the port of Sihanoukville, Cambodia last week but the cruise company claimed it "undertook significant precautions to ensure the health and safety of our guests and crew," before arriving at the port, the Holland America Line confirmed in its statement.

"On Feb. 10, 2020, all 2,257 passengers and crew were screened for illness including the taking of individual temperatures. No individual at that time was identified with an elevated temperature.

"Guests who were able to disembark in Cambodia underwent additional health screening and temperature checks. Furthermore, the passports of everyone on board were reviewed to ensure no one had traveled through mainland China in the 14 days prior to the cruise," the company said.

"During the voyage there was no indication of COVID-19 on the ship. The guest who tested positive did not visit the ship's medical center to report any symptoms of illness. An additional 20 guests who reported to the medical center during the cruise were tested by health officials for COVID-19, and all results were confirmed negative," it added.

The latest diagnosis of the coronavirus has highlighted the danger of the virus occurring in "unexpected places" and spreading via silent carriers who show no symptoms of it.

"This illustrates there is transmission occurring in unexpected places that we're not aware of," Jeff Duchin, health officer and chief of the communicable disease epidemiology section at Seattle and King County health department, told New Zealand's Stuff.

"The virus is moving very quickly and silently and presents a real challenge to containment," he added.

On Sunday, more than 300 Americans and their immediate family members were voluntarily taken off the Diamond Princess cruise ship, which has remained in the port city of Yokohama, south of Tokyo, since February 3 after a passenger was diagnosed with the COVID-19.

Medical authorities from the U.S. Department of Health and Human Services screened the passengers and concluded they had no symptoms of the respiratory virus, and were fit to travel on a chartered aircraft heading to the U.S.

Newsweek has contacted the Holland America Line for a comment.