More than 1 million seafarers are trapped working on cargo ships around the world due to the coronavirus

• There are more than a million cargo ship crew members believed to be working seven days a week without choice because ships cannot dock during the pandemic.
• Since they live in close quarters, without much access to health equipment, sailors are seen as potential coronavirus carriers.
• Seafarers, many of whom struggle with mental health issues, are likely to feel additional pressure on these lengthened trips.
• A 2019 Yale University study of cargo ship workers found that 25% reported depression and 20% contemplated suicide or self-harm.
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More than one million cargo ship workers are working seven days a week because the coronavirus pandemic means they're not being allowed to disembark.

According to the South China Morning Post, there are about 50,000 merchant vessels in the world, and each vessel has an average crew of 22 people. The BBC reported there are currently 1.6 million seafarers caught in limbo.

Typically, at the end of any given month, 100,000 sailors complete their contracts and are replaced by new workers flown to ships "at far flung ports," according to the Wall Street Journal's Costas Paris.

During the current crisis, though, that hasn't been able to happen.

Since these workers are living in close quarters without much access to protective equipment, they're seen as potential coronavirus carriers.

By April, China had prevented foreigners from entering the country, and Greece, a gateway for cargo into Europe, banned workers from taking shore leave or ships from changing crews.

Some nations are easing restrictions, including Spain, which designated seafarers as essential workers. India announced it would let crews change, but only if they were Indian.

These extended voyages are likely to put additional pressure on cargo crews, a sector already facing mental health issues: A 2019 comprehensive Yale University study of 1,572 sailors found that, over a two-week period, 25% of them reported depression, 20% had contemplated suicide or self-harm, and 17% experienced anxiety.

Low job satisfaction, harsh work environments, and inadequate training were cited as contributing factors.

Having contracts extended without a choice, and the uncertainty of when their next leave will be, could exacerbate the problem.

"On the surface, trade continues to flow," Claes Berglund, president of the European Community Shipowners' Associations, told the Wall Street Journal. "Below the surface, our crews are being challenged enormously. European shipping has reached a breaking point."