Burma's highly mobile migrant population may already be spreading the drug-resistant strain around the world.

BBC: Can Asia save Africa from drug-resistant malaria?

Mexico has always been conflicted over its massive migrant population.

NPR: Immigration Activists Target U.S. Businesses in Mexico

Other things being equal, immigrants are more likely to vote Labour than the population as a whole, yet the rise in London's migrant population did not stop the Tories' Boris Johnson from taking the mayoralty from Labour's Ken Livingstone in 2008 and holding on to it earlier this year.

ECONOMIST: Immigrants

Studies covering Eastern European migrants found them to be less likely to claim benefits than other migrant groups or the general population, the report said, adding that of those who claim benefits now, the majority receive child benefits.

BBC: Romanian and Bulgarian immigrant impact 'modest'

With the population in India increasingly migrant in nature, this payment infrastructure will enable a large populace to participate in the financial sector, opening new opportunities for growth.

ECONOMIST: Asia

Perhaps the most rapid change has taken place in North Carolina, where a technology and construction boom has sucked in hundreds of thousands of migrant workers, swelling the Hispanic population by more than 1, 000% since 1990.

ECONOMIST: Among the very poor, the American Dream is alive and well