An emergency room doctor at United Medical Center has tested positive for the novel coronavirus, a senior city official said Monday, the first known infection at the District’s public hospital in Southeast Washington.

A second doctor at the facility, a gastroenterologist whose spouse tested positive for the virus, also began to feel ill and went into quarantine last week, the official said.

The two cases highlight the risk posed by the coronavirus to a medical facility that houses some of the poorest, oldest and sickest patients in the Washington region. In addition to its patient beds, UMC operates a nursing home on one floor of its building — a facility that until last week was accessible from the main elevator that serves the hospital’s other areas.

Hospital officials on Friday barred outside visitors to the nursing home and placed limits on visits to all other patients. Only two visitors per patient are allowed during two-hour visiting periods that begin at 10 a.m. and 6 p.m. daily. No visitors under the age of 18 are being allowed into the facility.

UMC is Washington’s only full-service hospital east of the Anacostia River, serving predominantly African American neighborhoods whose residents struggle with severe disparities in health-care access even when a pandemic is not underway. The vast majority of residents in the hospital’s skilled nursing facility are Medicaid patients, many of them coping with chronic underlying conditions.

LaRuby May, chairwoman of the hospital’s board, said Monday that the hospital was mobilizing to protect patients and nursing home residents and following advice for preventing coronavirus infections issued by the Centers for Disease Control and Prevention. However, she declined to discuss specific steps that were being taken, referring those questions to a hospital spokeswoman.

“All of our patients are important to us, and we’re doing everything that we can,” May said.

UMC spokeswoman Toya Carmichael said the hospital has set up a separate waiting room and isolation area for patients who show flu-like symptoms. The hospital has distributed extra protective equipment to its staff and has ordered more such equipment, Carmichael said. UMC is currently using an external lab to test for the virus but is in the process of ordering its own test kits, she added.

Hospital officials put out a statement Monday that a staff member had tested positive for the coronavirus but did not disclose other details. Wayne Turnage, the District’s deputy mayor for health and human services and a hospital board member, told The Washington Post that the staff member was an emergency department physician. It was not immediately clear how the doctor contracted the virus.

The second doctor, a gastroenterologist, self-quarantined last week after beginning to feel unwell, Turnage said. The gastroenterologist’s wife had recently tested positive for the coronavirus after returning from travel abroad, Turnage said. He said that doctor has been tested and is awaiting results, which could arrive as soon as tomorrow.

Edward Smith, executive director of the D.C. Nurses Association, said the union was concerned about a lack of communication from UMC leadership about the hospital’s plans for combating the coronavirus and ensuring the safety of medical personnel. He noted that even before the arrival of covid-19 — the lung disease caused by the coronavirus — UMC was coping with dwindling financial resources.

Long dogged by complaints of poor care and mismanagement, the hospital has weathered repeated turnover in its leadership over the past decade. It is scheduled to close in 2023 and be replaced by a more modern hospital serving Southeast.

Smith said his concerns are not confined to UMC. The District’s network of hospitals has experienced other turmoil in recent years, including the closure of Providence Hospital in Northeast — another facility that served a disproportionate share of low-income patients.

When Providence closed last year, many warned that the elimination of its 283 hospital beds could come back to haunt the city.

“We don’t believe that the nation’s capital is prepared,” Smith said. “There’s already a major strain on all hospitals in the District of Columbia . . . and now with this pandemic, it’s dangerous.”