ÁPORO, Mexico — The money would arrive like clockwork: $300 every couple of weeks, sent by her husband, a day laborer and undocumented immigrant living in Indianapolis.

It was the only source of income for María Alejandre and six other family members in Áporo, a small town in the western Mexican state of Michoacán.

But more than four weeks have gone by since Ms. Alejandre’s husband last sent money, and with his work opportunities drying up amid the coronavirus pandemic, Ms. Alejandre is deeply worried.

“If the economy gets any more difficult,” she said, “well, we don’t know how we’re going to eat.”

The pandemic — and government measures to combat it — are snapping financial lifelines around the world. As millions of workers in the United States and elsewhere see their hours cut or lose their jobs entirely, many are no longer able to send money to relatives and friends back home who depend on these remittances to survive.