The Tenement Museum, on Manhattan’s Lower East Side, has always seemed fragile, with its creaky floors and cramped rooms in which striving immigrants once made their homes. Now it seems downright breakable.

The coronavirus pandemic has shuttered cultural institutions all over the world, withering their staffs and canceling long-planned initiatives. But the prospects are particularly dire for small institutions like the Tenement Museum, whose very survival is suddenly uncertain. They do not have large endowments or deep-pocketed donors, and have long depended on admission fees to keep the lights on.