As Philadelphia confronts the coronavirus pandemic, the city’s health department is working without its top epidemiologist.

Raynard Washington, Philadelphia’s chief epidemiologist since 2017, left the city for another job opportunity after his last day at work Friday. Washington’s exit had been expected since last month and was not related to the pandemic, city spokesperson Mike Dunn said. Washington’s departure “has not hampered our work in any way,” Dunn said in a statement.

In an interview with The Inquirer, Washington also said his departure left “no gaps” in the coronavirus response.

“My job as leader in the health department focused a lot more on community epidemiology, on what is affecting health in Philadelphia, which is different and separate than disease control — that’s a different chain of command,” he said, adding that the entire disease control team has been working on the response to the virus outside of his command.

The city’s infectious-disease epidemiologists report to Dr. Steve Alles, the department’s Disease Control director, Dunn said. “Dr. Washington was never himself involved in infectious-disease issues here,” he said.

Epidemiologists study diseases and how they spread in populations.

Other epidemiologists in the health department’s infectious-disease division have been working on the coronavirus, Dunn said. Raynard’s expertise is in chronic diseases. City Health Commissioner Thomas Farley has a degree in epidemiology and worked in the epidemic intelligence service for the U.S. Centers for Disease Control and Prevention. Deputy Health Commissioner Caroline Johnson is board-certified in infectious diseases, according to the department’s website.

Washington’s departure nevertheless raised concerns for a group of nurses when they learned of it Monday. Charito Morales, a nurse and local activist, said she and a group of nurses have been on calls with health officials to learn what the city is doing and what nurses should be telling the public.

It was during one of those calls Monday that officials told the group that Washington had resigned.

“He is the one who is supposed to guide this” local response to the pandemic, Morales said. “They actually need this person.”

Morales was surprised that despite having ample warning about Washington’s departure, officials had not named an interim chief or had a replacement lined up.

“The position is empty at this point because our efforts are focused on supporting the entire team of infectious-disease epidemiologists responding to the coronavirus, not sitting in interviews or asking people from around the country to fly here for an interview," health department spokesperson Jim Garrow said. “We are confident that our epidemiology capacity is enough to manage this outbreak."

Washington said he was responsible for a lot of the city’s health reporting, data sharing, and overall monitoring of health conditions in the city. And while he also oversaw strategic initiatives, he said that work was not directly tied to the coronavirus response.

“If I were still there, I would certainly be part of the team as people are pulled into” various response roles, he said. “But I’m not critical to chain of command.”

Washington said he had a full departure plan and made sure all of his duties were taken care of by others. He is also still available to them by phone.

“I am accessible to them to make sure there are no loose ends,” he said. “I believe they are in good shape. … I don’t foresee a gap.”