Thailand and Malaysia moved quickly to head off the coronavirus, sealing their borders, shutting down the movement of people and encouraging social distancing. They now face the delicate challenge of restarting their economies when the migrant workers they rely on pose one of the biggest risks of forcing another lockdown.

Temperature checks and mandatory virus tests are some of the measures becoming the new normal for the five million guest workers in the Southeast Asian nations. But the combination of cramped living conditions and language barriers make migrant labor vulnerable to a new round of infections.

Both Thailand and Malaysia are attempting to avoid a repeat of what happened in Singapore, which suffered a spike of infections from its 1 million strong low-wage foreign workforce, many of whom live in cramped dormitories. That would be a setback to the migrant labor market that has boosted incomes and economies across Southeast Asia.