Iqbal Hussein feels like a marked man. An itinerant labourer from rural Khulna district in Bangladesh, he now scraps for odd jobs in a market town 19 miles (30 km) south of Malaysia’s capital, Kuala Lumpur.

Last year, he agreed to pay a recruitment agency $2,400 to win a position on the production line of an auto parts manufacturer.

But in the wake of the financial crisis, that job is gone, and Hussein, like hundreds of thousands of migrant workers around the world, is stranded far from home, saddled with debts that will take years to repay.

And that’s if he manages to find regular work. Viewed with hostility by native Malaysians competing for the same increasingly scarce jobs, Hussein, 25, says he has to keep a low profile to avoid immigration officials looking for illegal immigrants.

On March 15, the Malaysian government revoked 60,000 work visas it had granted other Bangladeshis, and officials are now threatening to round up foreigners for deportation.

"I am hiding and avoiding places where Bangladeshi people gather,” says Hussein. If caught, he risks jail, a heavy fine, and even a whipping before being sent home.

Hussein’s plight reflects one of the burgeoning problems of the global downturn. Countries that built successful economies in part on the backs of cheap migrant workers now face upheaval in their labour markets.

In places like Taiwan, Malaysia, South Korea, and the Gulf states, companies are folding, factories are closing, and thousands are losing their jobs — meaning migrant workers like Hussein are being shoved out of the labour pool and into a tenuous half-life on the margins of the world economy.

The problem extends beyond the fate of individual workers. Migrants regularly send large chunks of their pay checks back home to support their families, providing much-needed capital to some of the world’s poorest countries.

The World Bank announced yesterday that these remittances to developing countries would likely shrink this year by 8%, after rising 9% in 2008 and 16% in 2007.

Nieves Miguelita M. Yabao, from Demaguete City in the Philippines, came to the gambling Mecca of Macau during that city’s recent construction boom. But when she arrived, she discovered the job she had been promised working at a casino lounge was no longer available.

"I haven’t been able to send money home,” she says. "Home has been sending me money and [my family say] there’s no food to eat.”

The estimates portend grim consequences: some 53 million people may fall below the poverty line if the financial crisis continues and remittances dip, according to the World Bank.

In the Philippines alone, up to five million people are sustained by money the country’s expatriate workforce — one of the world’s most disparate and omnipresent — sends home.

Some 10% of Bangladesh’s total GDP, and 16% of Nepal’s, comes from the remittances of pools of unskilled labourers working in Malaysia and the Gulf states.

The economic impact of remittances is even higher in Central Asia, where entire villages send their able-bodied men to Russia.

Tajikistan, for example, draws more than a third of its GDP from remittances, and the country’s economy will suffer badly as jobs in Russia dry up.

Observers warn of greater social traumas now facing migrant workers marooned at the foot of the global socio-economic ladder.

Because the economic situation is even worse in their native countries, many decide to stay on in their adopted homes even though they have lost their jobs and their work visas are no longer valid.

"They will settle to be illegal,” says Manolo Abella, a Bangkok-based expert on regional migration for the International Labour Organization.

"Migrants workers often tolerate all sorts of abuse and deprivation just to stay and earn a wage, to avoid being sent home.”

Recent cases of undocumented workers getting press-ganged into near slave-like conditions aboard fishing vessels in the river deltas of Southeast Asia have dramatized how vulnerable destitute migrants are to exploitation.

Abella also warns that women migrants may fall into the sex trade and become prey to networks of human traffickers. Support, though, is hard to come by in countries where unemployment is skyrocketing and competition for jobs fierce.

Oil palm plantations in Malaysia, which involve intense toil under the hot sun, were once the exclusive province of migrant labour, but laid-off Malaysians like former factory worker Palani Kandasamy are turning to this sort of work.

"The pay is lower, but it is impossible to live in the city without a job,” he says. Kandasamy now harvests oil palm fruit in a plantation south of Kuala Lumpur.

More than half a million Malaysians may lose their jobs this year. Faced with increasingly unhappy voters, the government is taking steps to ensure citizens find work.

Last week, the Home Ministry announced a "massive operation” geared at detaining and deporting some 1.5 million illegal workers, mostly Bangladeshis and Nepalis.

"We have to look after our own people first,” Home Minister Syed Hamid told TIME. "[The illegal migrants]better leave before the operation starts.”

There are virtually no safety nets for migrants caught in this mire, nor international regulatory regimes to oversee their recruitment and fair compensation.

The cash-strapped governments of countries like Bangladesh, Nepal and the Philippines are struggling to come up with solutions for their expatriate workers.

For example, The Philippines recently launched a lending program to help laid-off workers who have returned home to set up small businesses.

Shiladitya Chatterjee, an economist at the Asian Development Bank in Manila, says governments need to thrash out a regional system to deal with migrant grievances and to help stranded, indebted workers.

"Asia only recently woke up to the importance of this invisible export,” says Chatterjee about foreign workers. "There must be better regional cooperation.”

But such sentiment is likely to fall on deaf ears in host countries, where unskilled foreign labourers not long ago were welcomed as useful contributors to economic development.

The Malaysian Trade Union Congress (MTUC) once campaigned for the protection of migrants’ rights. But now they too are sounding alarm bells about the threat illegal workers pose to ordinary wage-earning Malaysians.

"Many remain in the country,” says Rajasegaran Gopal, the MTUC’s secretary general. "We have a foreign worker time bomb ticking away.”

TIME