A leading AIDS researcher who is also an expert in treating heroin addiction is the top candidate to head the Atlanta-based CDC, according to news reports.

Dr. Robert Redfield, 66, a professor of medicine at the University of Maryland School of Medicine, would replace Dr. Brenda Fitzgerald, a Georgia physician who resigned as CDC director in January after a news report about the purchase of tobacco stock for her investment portfolio after she assumed her job.

Redfield, if appointed as CDC director, would head an agency that has a strong Atlanta presence. The majority of the 23,000 CDC employees and contractors are based in the city and its suburbs.

Dr. Anne Schuchat, a veteran official with the CDC, has been serving as acting director.

The Washington Post reported that Redfield is well respected for his clinical work but at one time took controversial positions on HIV testing.

Redfield oversees a major clinical program providing HIV care and treatment to more than 6,000 patients in the Baltimore-Washington region and a care program that is part of the President’s Emergency Plan for AIDS Relief, the Post reported.

In the early 1990s, while he was an AIDS researcher in the Army, Redfield sparked controversy over an experimental AIDS vaccine that ultimately failed. The Post reported he had been known as a strong supporter of mandatory patient testing for HIV during the 1980s. This stand drew criticism at the time because effective treatments were not yet available and there was an intense stigma around having the virus, according to advocates and researchers.

“The controversy in the 1980s was that some of the policies he advocated and some of the organizations he was associated with were not embracing sound public health approaches to the AIDS epidemic and were stigmatizing of those who were infected,” said Jeffrey Levi, who was executive director of the National Gay and Lesbian Task Force and later became deputy director of the Office of National AIDS Policy under President Bill Clinton, the Post reported.

“The context that people have to remember is that during this time, people could be fired for having HIV; they could lose their health insurance for having HIV,” he said, according to the Post. “That’s why there was so much furor.”

The newspaper also reported that Redfield clashed with AIDS treatment advocates over whether to collect the names of those who tested positive rather than using anonymous identifying codes, according to a 2002 report in the AJC when he was among the candidates being considered to be CDC director under President George W. Bush. Dr. Julie Gerberding wound up being chosen by Bush.

HIV testing and data collection are not so controversial today. U.S. health officials encourage widespread testing, though it is not mandatory except for a few limited categories of people.

The CDC, which is federally run, takes a leading public health role in the nation and globally, especially in regard to infectious diseases such as Zika, Ebola and influenza.

The CDC director position does not require Senate confirmation. But Sen. Patty Murray of Washington, the ranking Democrat on the Senate Health, Education, Labor and Pensions Committee, sent a letter to the White House this month saying she and her Democratic colleagues intend to “thoroughly scrutinize” any candidate to ensure he or she is an “upstanding steward” of public health, the Post reported.

Murray’s letter listed more than a dozen criteria, including prioritizing science over ideology, resolving any conflicts of interest and leading the federal government in engaging in critical evidence- and science-based research and policymaking.

A formal announcement about Redfield could come as early as Tuesday, once the vetting has been finished, said an administration official with knowledge of the appointment, the New York Times reported.

Redfield also has years of experience treating heroin addicts, the Times reported. And he has been a longtime proponent of medical assisted treatment for addiction.