NAIROBI — Late Thursday, the State Department posted a request on its website and on Twitter to "encourage medical professionals seeking work in the U.S. on a work or exchange visitor visa (H or J), particularly those working on #COVID19 issues, to contact the nearest U.S. Embassy/Consulate for a visa appointment."

The announcement also indicated that those who were already in the United States on those visas should talk with their sponsors about extending them.

Routine visa services at U.S. embassies across the world were suspended March 20, as most embassies evacuated workers and shrank to skeleton staffs carrying out essential services.

On Friday, State Department officials clarified their original posting, saying they were only processing people already accepted for jobs or studies in the United States.

Ian Brownlee, the assistant secretary of state for consular affairs, said the United States was not seeking new applicants or giving preference to medical professionals. But he acknowledged that the initial message on the website was “not as clear as it might have been.”

“We’re ready to work with people who are already accepted into existing U.S. programs and had otherwise planned to travel to the United States,” he told reporters. “We are not going out looking for others. These are people who were ready to come in.”

While the State Department has suspended routine visa services, Brownlee said it still is processing visas for “certain cases.” Among those are visas for American couples seeking to adopt a child overseas, immigrants who might otherwise age out of eligibility and medical professionals who already had been accepted for work or study.

Asked why it was considered necessary to put out a statement singling out medical professionals working on the novel coronavirus, Brownlee said he would have to look into “how this all came to pass” before he could answer.

The initial announcement was widely panned on social media by users across the world who accused the U.S. government of promoting a potentially deadly brain drain of doctors and nurses away from countries with weaker health-care systems.

Others noted how difficult procuring these visas can be in normal times, often taking years to process, and were resentful that the rules would be changed so drastically in a moment of crisis.

Morello reported from Washington.