DALLAS — The refrigerator in Youngor Jallah’s small apartment broke down last week, and it did not take long for the stench of rotting food to grow unbearable. But when she reported the problem to the front office, the complex’s manager said that a repairman would not be sent until Monday.

That is the expiration date for the 21-day, self-imposed quarantine that Ms. Jallah, her partner and her four children have endured since the day her mother’s boyfriend, Thomas Eric Duncan, was hospitalized here with Ebola. Because her mother was at work, it was Ms. Jallah, 35, who last cared for Mr. Duncan, making him tea and handing him a thermometer — but, she said, never touching him — before summoning an ambulance.

The complex’s manager urged Ms. Jallah to move her food to the apartment across the stairwell, which has been empty since a new renter decided against moving in after hearing about the neighbors. When the landlord sent a maintenance man to deliver the key, he arrived wearing two pairs of rubber gloves.

So it has been in Quarantine Nation. As the Ebola scare spreads from Texas to Ohio and beyond, the number of people who have locked themselves away — some under government orders, others voluntarily — has grown well beyond those who lived with and cared for Mr. Duncan before his death on Oct. 8. The discovery last week that two nurses at Texas Health Presbyterian Hospital here had caught the virus while treating Mr. Duncan extended concentric circles of fear to new sets of hospital workers and other contacts.

Officials in Texas said Thursday that nearly 100 health care workers would be asked to sign pledges not to use public transportation, go to public places or patronize shops and restaurants for 21 days, the maximum incubation period for Ebola. While not a mandate, the notices warn that violators “may be subject” to a state-ordered quarantine.

When officials revealed that one of the infected nurses had flown from Dallas to Cleveland and back before being hospitalized, nearly 300 fellow passengers and crew members faced decisions about whether to quarantine themselves. The next day, a lab technician who had begun a Caribbean cruise despite possible exposure was confined to a stateroom. Medical workers, missionaries and journalists returning from West Africa — especially from Guinea, Liberia and Sierra Leone, where Ebola is rampant — are also staying home.