BANGALORE (REUTERS) - The US Centres for Disease Control and Prevention extended its "no sail order" for all cruise ships, as it looks to prevent the spread of the novel coronavirus pandemic.

The CDC new order says that cruise ships have to cease operations for up to 100 days, or the expiration of the Secretary of Health and Human Services'declaration that Covid-19 constitutes a public health emergency, or if the CDC Director rescinds or modifies the order.

The order, dated April 9, comes as the cruise industry takes a hit from the novel coronavirus outbreak, with trips across the globe either cancelled or suspended and refunds issued to customers.

Many cruise ship lines have already voluntarily suspended most of their operations.

Four of the cruise lines belonging to the world's largest cruise operator Carnival said last month they would extend the suspension of all voyages by a month to May while rival Royal Caribbean Cruises said it would return to service by May 12.

Currently, there are about 100 cruise ships remaining at sea off the East Coast, West Coast, and Gulf Coast, with nearly 80,000 crew onboard, the CDC noted, and said there are 20 cruise ships at port or anchorage in the United States with known or suspected Covid-19 infection among the crew who remain onboard.

The earlier "no sail order" was issued on March 14.

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