When his ship pulled into anchorage at Santos in Brazil last week, "Alona" had been at sea so long, he had missed his own wedding.

The assistant engineer from the Philippines had been on the same ship for nearly 16 months, despite three attempts to go home. He had not set foot on land since a brief shore leave in August 2019 and he almost never had a day off.

"I have daily jobs and reports which require me every day to work. Even on the weekends," says "Alona", who did not want to use his real name because he's worried he won't get any more work if he's identified.

Nine other crew members had been on board for just as long. It had taken a mental toll on everyone. Tempers sometimes frayed and morale was low.

An estimated 400,000 seafarers are waiting to go home. Most are trapped on ships because port authorities fear new Covid-19 infections and don't want them ashore. In some countries, crew changes are banned outright, while in others restrictions make them difficult to carry out.

Many are stuck on ships, often beyond the maximum of 11 months allowed under international treaty. Unions say it's a violation of their rights or even tantamount to forced labour. Some multinationals are also unhappy, because they fear industrial action could bring international shipping to a grinding halt.

'Damning indictment'

A recent survey of 926 seafarers by the International Transport Workers' Federation (ITF), provided exclusively to the BBC, found that 59% of respondents have had to extend their contract because they have been unable to arrange a crew change.

The survey also found that 26% had been aboard for more than the legal maximum, with some on board for as long as 18 months.

Seafarers are legally allowed to stop working if they go beyond their contract. In practice, that rarely happens, and for good reason.

"If we are in the middle of the sea far from any land, there will be a chance that our vessel may sink or an accident may happen, which may harm human life which would be a bigger problem for us. So I still work whether I like it or not to keep our ship working," says Alona.

Many are worried about fatigue and risks to safety. Asked to rate from zero to 10 the possibility of an "accident that could harm human life, property or the marine environment due to tiredness or fatigue", 71% chose five or higher, while 15% rated the possibility at 10.

Worse still, 8% said they weren't being paid and 30% said they had unmet medical needs.

The head of the Hong Kong Shipowners Association, Bjørn Højgaard, says he has heard of seafarers pulling teeth out because they couldn't leave the ship to go to a dentist.

In one particularly bad incident, Russian seafarer Alexey Kulibaba had a stroke, but was denied an emergency evacuation for several days after Indonesian authorities refused the ship permission to dock because of Covid-19 restrictions. One side of his body is still not working properly, and he still needs help with basic tasks.

His wife Oxana described the event as a tragedy, because a quicker response might have meant a better chance of recovery.

"We've never had that before," says ITF general secretary Stephen Cotton. "It's kind of the unwritten rule that if a seafarer is sick, you dispatch medical assistance. That's probably the most damning indictment of what's happened with lockdown culture."
'Logistical puzzle'

As Alona waited at anchorage on the Cape Henry, a 190m-long bulk carrier filled with rock salt, there were murmurings among the crew that their manning agency had finally arranged their repatriation. After similar attempts in China, Korea and Chile, he didn't want to get his hopes up.

As the ship moved from anchorage into port, there was bad news. The manning agency didn't complete paperwork in time and the replacement crew didn't make their flight out of Manila. They had been rebooked for the following day, so there was still hope. But he was worried.

His story is not unusual. Crew changes are always a "logistical puzzle", according to Mr Højgaard - who is also the chief executive of Anglo-Eastern, a manning agency that currently has 16,000 seafarers on ships around the world.

Travel restrictions make it harder still. Crews have trouble leaving their home countries and there are fewer flights. Port restrictions change quickly. Even those allowing crew changes often have requirements that can be difficult to meet in the short time a ship is in port.

"We all thought we'd turned the tide at the end of July, then we lost Singapore and Hong Kong at the same time," says Mr Højgaard. New infections among seafarers had set nerves on edge in both cities, and the authorities were reluctant to take chances.

It now costs roughly twice as much as usual to change a crew. Mr Højgaard suspects some smaller shipping lines and agencies might delay, hoping the next port will be cheaper or that more flights might open up, bringing down costs.
In limbo

Alona works on a ship because the pay is better than it is at home. But the job requires long stretches away from home.

He admits his fiancée is very patient. He plans to leave the industry when he's more financially secure.

"My plan is to make a lot of money while I'm still young, then start a business, so I don't have to return to the sea," he says. But if the job wasn't meant to be forever, it was sure starting to feel like it.

There was finally some good news. The replacement crew had departed from the Philippines. If they tested negative when they arrived in Brazil, Alona and his crew mates would finally head home. A positive test might still dash someone's hopes.
Tangled web

Seafarers have helped to keep the global economy running throughout the pandemic. But it has been a balancing act, according to Marc Engel, Unilever's chief supply chain officer.

Unilever operates in 190 countries and has factories in 70. So when China went into lockdown, it found inorganic chemicals elsewhere and in some cases reformulated products. Then, when Europe and India shut down, production moved back to China.

Back-up plans make a difference, but they don't work without shipping. For example, cocoa, soybean oil, vanilla and palm oil are all shipped from different parts of the world before they're made into soap or ice cream - which are then shipped elsewhere.

"I always say that soybean oil doesn't grow in the UK. So at the end of the day, you need a global supply chain," Mr Engel says.

He's worried that the global supply chain might no longer work if unions take industrial action. Along with Unilever, 30 other large consumer goods companies recently signed a letter to the UN secretary general outlining their concerns about "a major disruption of global supply chains" and the inadvertent creation of "a modern form of forced labour".

"I think we could be at a tipping point if the international unions are basically saying enough is enough. And you're hearing signals that that moment is close," says Mr Engel.

Unions have already taken action in Australia, where two ships have been detained by the authorities after unions reported them for keeping seafarers beyond the legal limit. But Mr Højgaard thinks simple exhaustion might be just as worrying.

"People will have mental health issues, or will be so fatigued they'll say, 'I can't do this any more.' It only takes one or two people, then you're not in compliance with your minimum safe manning certificate and the ship will stop."
'Mickey Mouse quarantine'

Still, governments and health departments are justifiably concerned about the pandemic. And many are unlikely to budge.

The state of Western Australia - where there have been only 700 cases in total - tightened restrictions recently, after four ships arrived with positive cases in the space of three weeks. In one case, a livestock carrier had 25 cases.

The Minister for Ports, Alannah MacTiernan, is not convinced Western Australia should lower its guard. Too many shipping firms don't take quarantine seriously enough, she says, singling out the Philippines and the Middle East for criticism.

"People have not been taking this seriously and they have Mickey Mouse quarantine," she says.

She says the shipping industry should instead look at its own operators and that crew changes should happen in the seafarers' home country.
A way forward?

While it might seem like a blunt rebuke, businesses, unions and the shipping industry agree in many respects. There have been cases where seafarers have breached quarantine before boarding. And there have been agencies that have been caught falsifying Covid test results.

There is broad agreement that a consistent standard might help. Everybody agrees on the need for proper infection controls. The issue is ensuring everyone adheres to them. Ports are more likely to open up when there's a trustworthy process.

Singapore - which has facilitated crew changes for more than 40,000 seafarers since March - is seen as a possible model. All crews must isolate for two weeks and have a test from an approved testing centre before they arrive to sign on in Singapore, where they stay isolated in floating accommodation for up to 72 hours before they board.

The ITF now has a pilot programme in Manila, where it is providing rooms for seafarers before they fly out to ports like Singapore. They stay in a room for two weeks, with a test at the beginning and the end, and the process is properly audited.
Going home

Alona finally made it to dry land on Monday. Along with his crew mates, he disembarked and went to a hotel to wait for his flight the next day. He was glad to touch land for the first time in over a year. But he was nervous too.

Ironically, after 16 months at sea where Covid-19 wasn't really an issue, he was for the first time faced with the pandemic that had kept him there. He disembarked in Brazil, where there are currently more than five million cases.

Still, there was plenty to celebrate.

"I am very much happy and excited. Like I said, this is the best feeling for a seafarer."