The coronavirus has changed that.

Diplomats, whose very jobs are to interact with foreigners and to represent 20 million Americans who are abroad at any given time, have been highly vulnerable to the pandemic as it swept around the world and into countries that have been slow to acknowledge its threat, many whose medical facilities are less than adequate to start.

Three State Department employees have died from the coronavirus so far, all of whom were foreign citizens who were hired by the embassies in their respective home nations. One was from Indonesia and another from the Democratic Republic of Congo. The State Department did not disclose on Friday where the third person was from, except to say that he or she was not an American citizen.

On March 20, the day before Mr. Young tested positive, President Trump described the State Department as the “Deep State Department” — a jab at what he sees as a disloyal diplomatic corps. He delivered it during a coronavirus briefing as he stood next to Secretary of State Mike Pompeo, who minutes later said of the president, “I know how much he values the people that work on my team.”

It was left to Representative Eliot L. Engel, the chairman of the House Foreign Affairs Committee, to defend the State Department staff. “These men and women aren’t a ‘deep state,’” Mr. Engel, Democrat of New York, said later. “They’re our leading edge in working to protect Americans in the farthest corners of the world.”

At the start of last week, there were only 43 kits available in Burkina Faso to test for coronavirus infection, Mr. Young said. The country currently has one of the highest numbers of infections in Africa — as of Friday, there were at least 288 confirmed cases and 16 deaths.